DISORDERS OF NUTRITION 11/29/10 PROTEIN-ENERGY MALNUTRITION (PEM):
• Inadequate intake of protein and calories – causes different problems based on the specific lack of material • Somatic proteins- SKELETAL MUSCLE
o affected in MARASMUS- (mid arm circumference) • Visceral proteins- organs, esp. LIVER
o affected in KWASHIORKOR- (albumin)
Kwashiorkor is protein malnutrition. Liver does not make enough albumin edema. SIGNS OF PEM:
• Loss of fat stores (subcutaneous fat) • Loss of muscle mass
• Loss of serum proteins (albumin, transferrin) • Loss of body weight
o < 80% is malnourished o < 60% is MARASMUS MARASMUS:
• < 60% body weight
• Diet lacks protein & carbohydrate
• Loss of muscle mass (somatic protein)- amino acids for energy
• Serum proteins (visceral compartment) NORMAL o Especially albumin
• Loss of subcutaneous fat (broomstick) • EMACIATION – loss of BOTH muscle and fat • Head appears too large; “stick figure”
• Multiple vitamin deficiencies
• Immune deficiency- esp. T cell immunity • Predisposed to infection
Child w/marasmus:
Head too big for body; broomstick limbs.
KWASHIORKOR:
• Protein deprivation > caloric deprivation
• 2nd Child is weaned too soon from mother’s milk and put on a high carbohydrate diet • MORE dangerous than Marasmus
• Severe loss of visceral protein
• Hypoalbuminemia causes generalized EDEMA which can mask the loss of visceral protein • Distended abdomen
• Subcutaneous fat and muscle are SPARED
Marasmus: Loss of subcutaneous fat reserves and muscle mass in patients with marasmus. (Wasting diseases can cause marasmus, ex: cancer patients.)
Test q: A 3y/o child has had a succession of respiratory infections during the past 6 months. On phys exam, the child appears chronically ill, listless, and underdeveloped. He is 50% of ideal body weight and has marked muscle wasting. Lab findings include Hgb of 9.4 g/dL, hematocrit 27.9%, MCV 75µm3, platelet count 182,000/mm3, WBC count 6730/mm3, serum albumin 4.1 g/dL, total protein 6.8g/dL, glucose 52 mg/dL, and creatinine 0.3 mg/dL. Which of the following conditions is most likely to explain these findings? Marasmus.
SIGNS OF KWASHIORKOR:
• Flaky Paint Skin- hypo- and hyper-pigment and desquamation • Hair loss or color change
• FATTY LIVER – due to loss of apolipoproteins; also small intestine atrophy/disaccharidase deficiency and diarrhea
o Malabsorption diarrhea • Apathetic with LOSS OF APPETITE • Multivitamin deficiencies**
• Immune defects and infections**
• Anemia- usually hypochromic/microcytic** • Cerebral atrophy**
• Pitting edema and ascites due to hypoalbuminemia
**both in MARASMUS AND KWASHIORKOR
Kwashiorkor is much harder to treat because even if they do eat, they cannot digest carbs. Test q: Children suffering from Kwashiorkor often fail to recover when proper nutrition is returned to their diet due to: intestinal atrophy.
SECONDARY PEM:
• MARASMUS-LIKE – chronic illnesses like cancer; loss of muscle and subcutaneous fat; normal serum proteins
• KWASHIORKOR-LIKE – acute illness like burns; normal fat and muscle; hypoalbuminemia and edema; VERY POOR PROGNOSIS
o Kwashiorkor-like illnesses are more severe. Seen in people w/severe trauma, especially burn patients. Test q: The malnutrition seen in severe burn patients is similar to that seen in: Kwashiorkor.
Robbins Table 10-20:
CACHEXIA:
• CANCER and AIDS • Loss of muscle and fat • Good appetite
o However, cannot maintain body weight by eating. • Higher metabolic rate
• Cytokines- TNF, interleukins, interferons • Proteolysis-inducing factor (PIF)
Kwashiorkor: swollen abdomen (due to fatty liver); periorbital edema
Figure: Metabolites have receptors – when these target cells turn on parts of the ubiquitin pathway, they destroy proteins. Could this be an attempt of the body to starve the malignancy? It ends up starving the body, too.
Figure: Terminal cancer patient with cachexia.
ANOREXIA NERVOSA: • Self-induced starvation • Like PEM plus:
• Amenorrhea • Hypothyroidism
• Scaly, yellow skin and lanugo • Osteoporosis-like
• Anemia, lymphpenia, hypoalbuminemia • HYPOKALEMIA AND CARDIAC ARYTHMIA BULIMIA NERVOSA:
• < ½ have amenorrhea
o Major difference between bulimia and anorexia • Weight and gonadotrophins near normal
• Hypokalemia and CARDIAC ARYTHMIA • Aspiration of gastric contents
• Mallory-Weiss Syndrome- laceration of the esophagus or stomach
• Boerhaave’s Syndrome- rupture of esophagus or stomach
Test q: A 28 y/o actress has a history of excessive weight gain and loss and also has a history of surgical repair of a Mallory-Weiss tear. She has had many cosmetic dental procedures. While shooting a new movie on location in England, she collapses and cannot be resuscitated. The most likely cause of her sudden death is: Cardiac arrhythmia secondary to hypokalemia. (Other choices: MI, Myocarditis secondary to diphtheria, Cardiac arrhythmia secondary to hypercalcemia, or Ruptured esophageal varices.)
Vitamin Deficiencies and Trace Element Deficiencies: • VITAMINS: Table 9-9, Robbins p. 438
• TRACE ELEMENTS: Table 9-10, Robbins p. 439 VITAMINS:
• Fat Soluble- A, D, E, K • Water soluble- B’s, C, Folate
• Fat soluble vitamins are more readily stored, BUT they are poorly absorbed in fat malabsorption disorders o Chronic diarrhea vitamin deficiency
• ENDOGENOUS- D, K and Niacin
o Mainly Vitamin D. Skin is effective at production if the person gets adequate sunlight. • DIET- all the others
• Vitamin Deficiency can be PRIMARY (diet) or Secondary (malabsorption)
VITAMIN A (RETINOL):
• Robbins Figure 9-25- Vitamin A “cycle” • Vitamin A- liver, fish, eggs, milk, butter
• “pro-vitamins”- (beta-carotene)- carrots, spinach are converted to Vitamin A in the body
• Fats/carotenes/retinoids require bile, pancreatic enzymes and antioxidants for digestion and absorption
• Vitamin A stored in ITO CELLS in the liver; 6-month supply VITAMIN A FUNCTIONS:
• Night vision
• Growth and differentiation of mucus-secreting epithelium • Immunity (children)
o Especially important in measles virus. If Vit A deficient, also more likely to get disease if infected because pulmonary epithelium is abnormal.
VITAMIN A DEFICIENCY: • Night blindness
• Xerophthalmia (dry eye)- keratinized squamous epithelium replaces mucus-secreting epithelium
• Bitot spots (keratin debris) and keratomalacia (destruction of the cornea)
• Squamous metaplasia in LUNG (infections) and BLADDER (stones) • Increased mortality in measles and diarrhea
Test q: An epidemiologic study observes increased numbers of respiratory tract infections among children living in a community in which most families are at the poverty level. The infectious agents include Streptococcus pneumoniae, Haemophilus influenzae, and Klebsiella pneumoniae. Most of the children have had pneumonitis and rubeola infection. The study documents increased rates of keratomalacia, urinary tract calculi, and generalized papular dermatosis in these children. A deficiency of which of the following vitamins is most likely to be present in these children? Vitamin A. REPEATED x2
Spots/lesions/destruction of cornea. See squamous metaplasia in kidney or lung. Corneal destruction. VITAMIN A TOXICITY:
• Increased intracranial pressure • Papilledema, headache, vomiting
• Bone pain and hypercalcemia (but not major effect)
VITAMIN D:
• CALCIUM AND PHOSPHORUS levels
• Diet or endogenous synthesis in the skin (sunlight); about 80% of required Vitamin D can be produced endogenously
• Fish, plants (ERGOSTEROL), grains
• Robbins Figure 9-27 for Vitamin D metabolism • Kidney production of Vitamin D:
1. Feedback inhibits α-1-hydroxylase
2. Hypocalcemia stimulates PTH which activates α-1-hydroxylase 3. Hypophosphatemia activates α-1-hydroxylase directly
Above: Terminal step in making biologically active Vitamin D is α-1-hydroxylase. If Vitamin D levels decrease, there will be decreased calcium/phosphate absorption from the intestine and lower serum calcium/phosphate levels. This leads to parathyroid glands mobilizing calcium from the bone and increasing reabsorption of calcium from the kidney. However, we maintain calcium levels at the expense of phosphate levels. Bone deformities are usually because of phosphate, not calcium (since the body is so good at regulating calcium).
VITAMIN D FUNCTIONS:
• Ca and P absorption in the intestine • Mobilization of bone Ca (with PTH)
• Stimulates PTH-dependent re-absorption of Ca in the distal renal tubule VITAMIN D DEFICIENCY:
• HYPOCALCEMIA and loss of bone: RICKETS or OSTEOMALACIA
• Loss of phosphate bony destruction • Robbins Figure 9-29 lists causes of Rickets and
Osteomalacia:
1. < diet or sunlight
2. pancreatic insufficiency or obstruction • Malabsorption of Vitamin D 3. drugs, liver disease, renal disease 4. phosphate depletion
• In rickets and osteomalacia there is an excess of UNMINERALIZED matrix
o Problem is with mineralization. Contrast: Vitamin C deficiency is a problem with osteoid production (lots of mineral, not enough osteoid).
• In children (rickets) endochondral bone growth is also disturbed
Figure: Vitamin D Metabolism
Vitamin D has to be metabolized in two steps to its active form. It gets hydroxylated in the liver and kidney to get to its dihydroxy form (active form). This means that liver or renal disease can lead to Vitamin D problems since you cannot get to the biologically active form.
Vitamin D Deficient Normal
Rickets. A, Detail of costochondral junction in which the palisade of cartilage is lost. Darker trabeculae are well-formed bone; paler trabeculae consist of uncalcified osteoid. B, Compare with normal costochondral junction of a young child. Note cartilage palisade formation and orderly transition from cartilage to new bone.
Above: Rickets – bowed legs, pigeon chest
Disorder, diminished mineralization
RICKETS:
• Osteoid with inadequate mineralization • Disorganized fibroblasts and capillaries • Microfractures
• Deformed bones
• Abnormally-shaped (square) head, “rachitic” rosary, pigeon breast, and bowed legs • Buzzword: overprotected child
• Kids – rickets. Adults – osteomalacia.
OSTEOMALACIA:
• Abnormal bone remodeling
• Inadequate mineralization of new bone • Fractures and microfractures
• Vertebrae and femoral neck
• Note: osteoporosis is caused by inadequate osteoid protein and defective Vit D receptors w/ demineralization
Figure: Normal bone vs. Osteoporosis vs. Osteomalacia Osteomalacia: volume of bone is same, but lots of the bone is not mineralized. Leads to fractures.
Osteoporosis: Net loss of bone (could be 50%).
VITAMIN D TOXICITY: • Metastatic calcification
• Hypercalcemia, hyperphosphatemia • Low PTH
Vitamin D Antimicrobial Effect: • Toll-like Receptors (TLRs) • Increase in Vitamin D receptor • Synthesis of Cathelicidin
• Resistance to infections, especially: inhibition of M. tuberculosis o People who are Vitamin D deficient are predisposed to TB. When organisms interact w/cell, they interact w/TLRs. This enhances the production of Vitamin D.
VITAMIN E:
• Alpha-Tocopherol • “antioxidant”
• Deficiency- nervous system- degeneration of posterior column axons
• Loss of position and vibration sense; ataxia, muscle weakness
• “looks like” B-12 deficiency
• Hemolytic anemia of premature infants
VITAMIN E AND HEART DISEASE:
• NO protection from coronary heart disease • NO decrease in coronary events
• AND no benefit in dementia prevention So do not need to take megadoses of Vitamin E – why are people doing it?
VITAMIN K:
• Clotting factors II (prothrombin), VII, IX and X are carboxylated in the liver and Vitamin K is a cofactor
• Also, carboxylation of protein C and S (anticoagulants) • Vitamin K is “recycled” in the liver and gut bacteria make the
vitamin, but some dietary source is required VITAMIN K DEFICIENCY:
• Bleeding, especially intracranial in infants; also bleeding umbilical stump
• Babies receive Vitamin K in case they are deficient.
Test q: Vitamin K dependent factors and proteins include all of the following EXCEPT: VIII. (Other choices: II, VII, X, Protein S)
Test q: A Caucasian infant presents w/failure to thrive and chronic diarrhea. There is oozing from a recent skin laceration. Stoll sample testing reveals steatorrhea. Diagnosis: Vitamin K deficiency.
Test q: An infant born at term has Apgar scores of 8 and 9 at one and five minutes. The infant appears healthy, but three days after birth, there is bleeding from the umbilical cord stump, and ecchymoses are observed over the buttocks. Seizures soon develop. A deficiency of which of the following nutrients best accounts for these findings? Vitamin K (Other choices: Iron, Vit E, Folic acid, Iodine)
THIAMINE:
• Not in polished rice, white flour or refined sugar
• TPP is a cofactor in oxidative decarboxylation and deficiency of thiamine results in DECREASED ATP
• Cardiovascular and nervous system problems • ¼ of all alcoholics are thiamine deficient THIAMINE DEFICIENCY:
• Dry beriberi (polyneuropathy)- myelin degeneration
• Wet beriberi (cardiovascular)- vasodilitation produces heart failure and edema
• Takes more pressure to pump blood through dilated vessels heart failure.
• Wernicke-Korsakoff Syndrome- Wernicke – ataxia/confusion; Korsakoff – amnesia, confabulation
NIACIN: Below: Skin lesions of pellagra. • NAD and NADP are coenzymes for dehydrogenases
• Grains, legumes and seed oils
• Deficiency- PELLAGRA (3 D’s): dermatitis, diarrhea (epithelial atrophy) and dementia (posterior column changes as in B-12 deficiency)
Test q: Over the past year, a 55F has had worsening problems w/memory and the ability to carry out tasks of daily living. She has had watery diarrhea for the past 3mo. Phys exam shows red, scaling skin in sun-exposed areas. The deep tendon reflexes are normal, and sensation is intact. Which of the following is the most likely diagnosis? Pellagra. NIACIN AND HEART DISEASE:
• High doses (1-6 grams per day) • Lowers LDL
• Lowers triglycerides • Increases HDL
Many physicians combine statins and niacin for therapy. Niacin can necrose the liver, so be careful – patients on niacin therapy must have their liver enzyme levels checked.
Test q: Which vitamin supplement can be used to lower LDL and Triglycerides and increase HDL? Niacin. VITAMIN C (ASCORBIC ACID):
• (Citrus) fruits and vegetables • Bone disease in growing children • Hemorrhage and poor wound healing in
children and adults
• Vitamin C is a cofactor in formation and maturation of procollagen
• Hydroxylation is impaired and crosslinks are not formed
• Antioxidant??? VITAMIN C DEFICIENCY:
• SCURVY
• Capillary and venule walls are weak with hemorrages (purpura and ecchymoses) • Trauma – hematoma and hemarthrosis
(joints – as in hemophilia)
• Child- too much cartilage and not enough osteoid protein); bowed legs and deformed chest
• Bacterial infection associated with gingival hemorrhage
Vitamin C Deficiency Remember, rickets is a problem with mineralization (osteoid is fine). Vitamin C deficiency is a problem with osteoid (mineralization is fine).
Dental problems Corkscrew hairs and perifollicular petechiae in scurvy. Above: Vitamin C Deficiency. Scurvy – gum problems, bleeding problems, bony deformities, abnormal wound healing, corkscrew hair formation.
FOLATE:
• Marginal body stores
• 20% of Americans have low Folate • Neural tube defects in the fetus • Macrocytic anemia
In B12 deficiency, get anemia AND CNS problems. In folate deficiency, just get anemia.
Zinc Deficiency: • Acrodermatitis • Anorexia
• Growth retardation • Impaired wound healing • Hypogonadism
Pathology in the Recognition of Emerging Infectious Diseases and Bioterrorist Events 11/30/10 “… one can think of the middle of the twentieth century as the end of the most important social revolution in history, the virtual elimination of the infectious disease as a significant factor in social life.” -- Burnet, 1962
Figure: About 15 million (>25% of 59 million) annual deaths worldwide are the direct result of infectious disease. Respiratory infections lead the list. Also AIDS, diarrheal illnesses, TB, vaccine-preventable diseases, etc.
What are emerging infectious diseases? • Incidence increased in past 20 years • New infections from changes in
known organisms
• Known infections spreading to new geographic areas or populations • Previously unrecognized infections
appearing in areas undergoing ecologic transformation
• Old infections reemerging through antimicrobial resistance or
breakdowns in public health • “Deliberately emerging” infectious
diseases (e.g., the 2001 anthrax bioterrorist attack in the US)
Infectious Disease Mortality in the United States, 1980-1996:
Article reported that 73% of hospital autopsies had an infectious disease. >60% of these were pneumonias. In 43% of cases, the infectious disease diagnoses were unknown clinically.
Infectious Disease Pathology & Public Health:
• Pathologists among 1st health care workers to encounter infectious disease outbreaks • Pathologists are in excellent position to discover emerging infectious diseases
• Collaborative research – Clinicians – Microbiologists – Veterinarians – Epidemiologists
• Many examples of recent emerging infectious diseases diagnosed through autopsies • Autopsy is increasingly viewed as an effective surveillance tool
– Pathologic specimens can serve as sentinel indicators of emerging pathogens Factors in the Emergence of Infectious Diseases:
• Human demographics and behavior • Human susceptibility to infection • Technology and industry
• Economic development & land use • International travel & commerce • Microbial adaptation & change • Climate & weather
• Changing ecosystem s
• Breakdown of public health measures • Poverty & social inequality
• War & famine • Lack of political will • Intent to harm
Emerging Infectious Diseases With Significant Contributions By Pathology: Legionnaires’ disease
AIDS
Cryptosporidiosis Microsporidiosis Cyclosporiasis Cat scratch disease
Acanthamoeba & Balamuthia infections
Helicobacter pylori disease Ehrlichiosis/other Rickettsioses Hantavirus pulmonary syndrome Ebola virus hemorrhagic fever Leptospirosis
Prion diseases Anthrax West Nile virus SARS coronavirus
Avian influenza A H5N1 (chickens & humans)
H1N1 2009 (swine flu) Emerging Infections Now Being Investigated in Latin America:
• Middle aged man with mucocutaneous lesion • Mucocutaneous biopsy (H&E)
• 21 patients with free-living amoebiasis in Lima, Peru since 1985, 21 of whom died.
• Samples from 10 autopsies identified as Balamuthia
mandrillaris
To some pathologists, the H&E sample may look like it contains macrophages, but they are amoebae. Samples were mistaken for cancer, but they were actually Balamuthia mandrillaris.
Test q: A 56M presents w/ulcers and mucocutaneous lesions around his nose and
mouth after a trip to South America. A skin biopsy shows ameboid microorganisms and mixed inflammation. Erythrophagocytosis is not present. Gram stain and GMS (silver) stains show no microorganisms. Diagnosis? Balamuthia mandrillaris.
Mucocutaneous Leishmaniasis (Espundia [Leishmania braziliensis]) Skin biopsy: Granulomatous inflammation with
amastigotes (leishmanial forms) in macrophages These are about the size of Histo. Have dots inside called amastigotes.
Anthrax scare in Fall 2001.
Old World Leishmaniasis in US Military & Civilian Workers: Iraq, Kuwait, Afghanistan
• >600 cutaneous (Leishmania major & L. tropica) • 4 cases visceral (L. infantum & L. donovani)
• Vector: sand flies of Phlebotomus genus; only the female bites • Baghdad boil: closed, nodular, chronic skin granuloma that ulcerates • Dx: skin bx (culture, PCR)
• Rx: sodium stibogluconate or alternative other drugs
Emergence of Community-Associated Methicillin Resistant Staphylococcus
aureus (MRSA):
• MRSA have been an increasingly important cause of healthcare-associated (HA) infections since 1970s
• 1990s-present, community-associated (CA) infections emerged and recently considered “epidemic”
• CA-MRSA infections are mainly skin infections – Disease Syndrome (%) – Skin/soft tissue 1,266 (77%) – Wound (Traumatic) 157 (10%) – Urinary Tract Infection 64 (4%) – Sinusitis 61 (4%) – Bacteremia 43 (3%) – Pneumonia 31 (2%) Outbreaks of MRSA in the Community:
• Clusters of skin infections in various settings investigated by CDC: – Sports participants
– Inmates in correctional facilities – Military recruits
– Daycare attendees
– Native Americans / Alaskan Natives – Men who have sex with men – Tattoo recipients
– Hurricane evacuees in shelters
• Often present as a boil or abscess. Patients frequently recall a “spider bite”
Test q: A 32M professional football player (not a quarterback) presents with a history of spider bite on his back. The site is now ulcerated, painful, and erythematous. The patient has fever of 102F. You would expect a Gram stain of the tissue to show: Gram-positive cocci in clusters.
Factors that Facilitate Transmission: • Crowding
• Frequent Contact • Antimicrobial Use • Compromised Skin
• Contaminated Surfaces and Shared Items • Cleanliness
• Lack of Handwashing! INVASIVE MRSA:
• Estimated number of people with serious MRSA infections (invasive) in 2005 was ~94,360, of which ~18,650 died.
• Although most invasive MRSA infections are healthcare-associated, strains traditionally associated with community transmission are now being identified in healthcare.
o Mostly in healthcare-associated cases o These are life-threatening invasive infections
MRSA Strain Characteristics Were Initially Distinct*:
MRSA in Healthcare MRSA in the Community
Prevalent genotypes (U.S.) USA100, USA200 USA300, USA400
Antimicrobial resistance Multiple agents Few agents
SCCmec (genetic element carrying
mecA resistance gene) Types I-III Types IV, V
Panton-Valentine Leukocidin (PVL)
toxin gene Rare Common
Caption from slide: These community strains do not appear to have been transferred from the hospitals. Patients with MRSA acquired in the community usually have no previous contact with healthcare centers. Clinical manifestations are also different, Community strains cause mostly skin and soft tissue infections, but rarely cause upper respiratory or urinary tract infections, which are common with healthcare strains. The community strains are only resistant to beta-lactams and sometimes other antimicrobial group, in contrast to the multi-resistant pattern of the healthcare strains. This different antimicrobial susceptibility is explained by a distinct genetic background, and, although still in debate, the difference in clinical manifestations may be due to the presence in community strains of toxins such as PVL (Panton Vanlentine Leukocidine), which causes severe inflammation.
Can use mecA types to isolate community-acquired vs. healthcare-acquired strains.
Test q: The Panton-Valentine Leukocidin (PVL) Toxin Gene is present in: Community-acquired MRSA. (Other choices: Nosocomial MRSA, Nosocomial C. difficile; Community-acquired C. difficile; Enterococcus fecalis)
Test q: A 50F is admitted for a right knee replacement. The surgical procedure was a success, but 3 days (72hr) post-operation, the surgical site is red, warm, and swollen w/drainage of pus. Real-time PCR is performed on the pus and is (+) for Staphylococcus aureus w/MecA gene present. This history is consistent with: Nosocominal MRSA. (Other choices: Community-acquired MRSA; S. aureus, methicillin susceptible; Coagulase-negative
staphylococcus; Viridans streptococci)
Distribution of PFGE types (CDC) among MRSA isolates from nosocomial bloodstream infections: PFGE type No. (%) ofnosocomialcases (n = 49)
USA300* 10 (20)
USA100 21 (43)
USA500 18 (37)
USA800 0 (0)
*Note: USA300 strain traditionally associated with transmission in the community now being identified in healthcare. Screen for MRSA carriers by doing PCR probe on the nasal swab material. This aids in predicting who is a carrier or at risk (esp. in ICU). Can give special baths, swab, in order to aid in cutting down on the spread. Clinicians, med students, and others coming into contact w/patients MUST WASH HANDS. Also – wear gloves and other barriers to aid in avoiding spread.
Emerging Diarrheal Diseases: Cholera Outbreak – Haiti, 2010:
Outbreak occurred in dark blue area of map, along the river. Victims worked in rice fields and drank untreated water. They would practice open defecation in areas that contaminate water supply.
“Haiti’s cholera part of old pandemic: CDC”*
• Cholera epidemic has killed >1,000 (thousands hospitalized)
• Haiti – is the latest country affected by an ongoing global pandemic that began in Indonesia 49 years ago • Due to V. cholerae serogroup O1, serotype Ogawa, biotype El Tor
• Likely initiated in one event - sanitation system already in chaos due to devastating earthquake (January 2010) Cholera:
• Incubation time usually 18-40 hrs, followed by nausea, abdominal rumbling, then massive watery diarrhea • Most infections mild-moderate, ~ 5% develop severe disease
• Morbidity & mortality due to dehydration so severe as to elicit shock & multiorgan failure; many die on first day • Dx: stool culture ([TCBS] thiosulfate citrate bile sucrose agar), biochemical ID on isolate; agglutination with
specific antiserum, PCR Treatment:
• Early, rapid replacement of water & electrolyte deficits with oral rehydration solution (ORS) is mainstay of treatment
• ORS: use commercially prepared if available. Or to prepare- for 1L purest available water, add 2.6 g NaCl, 2.9 g trisodium citrate, 1.5 g KCl, & 13.5 g glucose (or 50 g boiled & cooled rice powder)
• IV replacement fluid: Ringer’s lactate with extra K+
• Antibiotics are secondary to rehydration with ORS & mainly shorten duration of diarrhea (e.g., tetracycline 500 mg po 4 tunes daily)
• Haiti had not seen cholera for 100 years; conditions there are ideal for its spread (e.g., lack of safe drinking water, inadequate sanitation, contaminated food, 1.3 million displaced persons, torrential rains and flooding)
• 1 case confirmed in Florida - a woman who returned from visiting family Haiti (11-17-10)
Test q: A 25M medical student joins a medical missionary trip to South America. Shortly after arrival he develops watery diarrhea. Stool exam reveals no RBCs or WBCs. The most likely etiology for his illness is: Vibrio cholerae.
Test q: A 25F has sudden onset of severe profuse, watery diarrhea. Over the next 3 days, she becomes severely dehydrated. Lab studies of the diarrheal fluid shows microscopic flecks of mucus but no blood and no WBCs. The woman is hospitalized and receives IV fluid therapy for 1 week. Diagnosis? Cholera.
Emerging Causes of Diarrheal Disease:
• Vibrio cholerae O1 emerged in Peru (1991) then spread throughout South & Central America (Northern Indiana
outbreak due to contaminated food brought in suitcase by family member)
• Shiga toxin-producing E. coli O157:H7 (emerged in 1982) leading cause of post diarrheal hemolytic uremic syndrome (HUS) in N. America
• Cryptosporidium parvum - 1993 Milwaukee waterborne outbreak involving > 300,000 people
• Cyclospora cayetanensis - 1996 in US & Canada from raspberries imported from Guatamala
• Salmonella enteritidis - 2010 US outbreak associated with contaminated eggs (500 million recalled from Iowa
farms)
Clostridium difficile: emerged in 1970s
• Anaerobic sporeformer
• Antibiotic associated diarrhea and colitis
• Spectrum of pathologic findings (e.g., pseudomembranous colitis, non-specific inflammation of colon, unremarkable mucosa)
• The major cause of nosocomial diarrhea; potentially serious threat to immunocompromised patients; spores on hands, bed sheets, surfaces in hosp environment
• Dx: Rapid real-time PCR assays (excellent sensitivities > 93% & specificities > 95%); vs EIAs for toxins A&B (low sensitiviities 50-70%)
• Or gold standard culture for toxigenic Cdiff (using cycloserine, cefoxitin, fructose agar [CCFA] or a spore selection technique) and ID - but too slow!
Test q: The most common cause of nosocomial (hospital-acquired) diarrhea is: Clostridium difficile.
Figures: Pseudomembranous colitis. Yellow spots – plaques on top of ulcerated areas of the colon. See pseudomembrane formation w/sloughed material coming to surface. H&E: dots = inflammatory cells. Tremendous disruption/ necrosis of the gut epithelium.
Reemergence of Clostridium difficile:
• C. difficile originally defined as the cause of antibiotic-associated
diarrhea (CDAD & colitis in 1978 --- [or “CDI” today])
• Subsequent studies provided vast amount of information re its pathophysiology & Rx
• CDAD has a known cause (toxins A & B), established risks (antimicrobial exposure, acquisition of C. difficile, advanced age, underlying illness, immunosuppression, gastric acid suppression), & effective Rx (oral metronidazole or vancomycin)
• Recent renewed interest in C. difficile in recognition of disease that’s more frequent, more severe & more refractory to standard Rx
• These observations are explained by presence of new strain of C.
difficile called BI/NAP1/027 (or toxinotype III) that produces more
toxin A & B in vitro, produces binary toxin that is of uncertain significance, & is resistant to fluoroquinolones…
Test q: A 30F is being treated w/proton pump inhibitors for Zollinger-Ellison syndrome. She develops a urinary tract infection during hospitalization and is treated w/a Quinolone antibiotic. She develops diarrhea 3 days later and you order a stool: Assay for Clostridium difficile toxin.
Structure of toxins A and B Genes:
• tcdD Encodes positive regulator for toxin A and B production.
• tcdC Encodes negative regulator for toxin A and B production.
• tcdE Encodes a porin protein → important for
toxin release from cell?
• With normal tcdC gene expression, little toxin is produced in log growth.
• Epidemic strain: PFGE type BI/NAP1/027
• Positive for binary toxin & 18-base pair deletion of tcdC gene.
• With deletion of the tcdC gene → 16X more toxin A and 23 X more toxin B is produced in vitro in both log and stationary phases of growth.
• This causes more severe disease (↑ diarrhea, ↑spores → epidemic) Epidemic strain of C. difficile (BI/NAP1/027):
• Reported from 40 US states & all the Canadian provinces. • More potent, easier to spread, resistant to quinolones. Diseases Caused by Agents in Weapons Developed by USSR:
• Anthrax* • Tularemia* • Plague* • Brucellosis • Q fever • Smallpox
• Marburg hemorrhagic fever • Glanders*
• Melioidosis *Antibiotic-resistant agents stockpiled
Research Topics in USSR Biological Warfare Laboratories: • Typhus
• Venezuelan equine encephalitis virus • Botulism toxin • Dengue virus
• Russian spring-summer encephalitis virus • Marburg virus
• Ebola virus • Lassa virus
• Bolivian hemorrhagic fever • Argentine hemorrhagic fever
Above: C. difficile. Vegetative cells capable of growing on agar plates. Spores are refractile when you focus on them. Very difficult to treat patient and eradicate all the spores – relapse common.
Hemorrhagic Fever Virus Infection of Liver: Ebola Virus:
See cytoplasmic inclusions w/very sharp edges. Filovirus Immunohistochemistry:
Viral particles light up with the immunostains for Ebola virus.
Get hemorrhages in the skin, conjunctiva, mouth, various body orifices.
Hemorrhagic Fevers in Which Lympho-histiocytic Vasculitis is Prominent: • Rocky Mountain spotted fever (Rickettsia rickettsii [tick])
– Clinically. 2-14 d incubation pd., abrupt onset, fever, HA, myalgia, hemorrhagic skin rash, (d 3-6), CNS symptoms, & enlarged spleen & liver. Eschar (dark scab) at site of tick bite.
– Pathology. Rickettsia divide in endothelial cells of small vessels of skin & viscera, esp. in CNS – swollen or necrotic endothelial cells, perivascular hemorrhage, lymphocytes & macrophages.
– RM spotted fever shares characteristics w/typhus – but typhus transmitted by louse. • Typhus fever (R. prowazekii [louse]).
Rocky Mountain Spotted Fever: IU Student: Fall 2004 RMSF: Note thrombosed vessel & vasculitis.
Rash on entire body - includes palms of hands & soles of feet. Severe mental status changes – brain involvement w/rickettsial disease. Pinpoint petechial rashes on palms and soles. Organism grows in endothelial cells (above, right).
Typhus Nodule in Brain Perivascular cuffing w/edema and hemorrhages
in brain parenchyma. There was a capillary or venule right here in this view.
Below: Bolivian hemorrhagic fever – hemorrhage in conjunctiva.
Diagnosis of Rickettsial Diseases:
• Direct detection: Dx of Rocky Mountain spotted fever & other rash producing rickettsioses by immuno stains of rickettsiae in skin biopsies of rash & eschar lesions (e.g., direct fluorescent antibody [DFA])
• Serologic diagnosis: using the “gold standard” indirect FA, EIA or another immuno method.
Test q: A 22F suffers a tick bite on a hike in southern Indiana. She develops fever w/a total-body rash that includes palms of her hands. Biopsy of the rash shows thrombosed blood vessels. Swollen endothelial cells contain tiny “dots” on Giemsa stains. Diagnosis? Rickettsia rickettsii.
Must be protected when working w/rickettsial and hemorrhagic fever diseases. Biosafety level 4.
Another Rickettsial Disease in Indiana:
• Human Granulocytic Ehrlichiosis (now called Anaplasmosis)
• Two cases in Indiana: summer 2006 • Agent: Anaplasma phagocytophilum
• Vector: ticks (Ixodes – found in northern part of the state)
• Dx: microscopy of limited value; serology & DNA probe tests are methods of choice…
Fatal transfusion and transplant associated cases of Babesiosis in Indiana:
1. Babesia microti. Contracted by 61 y/o woman with end-stage renal disease & CHF who received 4 RBC units for GI bleeding. Rx = quinidine & clindamycin + exchange transfusion. 1 of the transfused RBC units showed evidence of B. microti by PCR.
2. Babesia MO1. Babesiosis is a red blood cell parasite that causes hemolysis with varying severity. It is usually transmitted by the deer tick Ixodes scapularis. However, this 73 yo woman who had undergone liver transplantation & splenectomy 2 years ago had neither tick-bite nor transfusion since the time of her transplant.
Northeast part of the US – Martha’s vineyard, Rhode Island, etc. Can see very tiny ring form that resembles P. falciparum malarial forms.
Also in Indiana Recently…
• “Indiana girl dies of rabies”
• INDIANAPOLIS, Nov. 3, 2006 (UPI) -- A 10-year-old Indiana girl believed to have been infected by a bat died of rabies early Thursday.” … The child… “ had been hospitalized since Oct. 7 at the Riley Children's Hospital in Indianapolis, the South Bend Tribune reported.
• Investigators say the fifth-grader is believed to have been bitten by a bat in June.
• “Rabies is always fatal once symptoms develop.”
• This was the first human case of rabies in an Indiana resident since 1959…
Above: Morulae (intracellular organisms). See structures inside neutrophils – morulae seen here in neutrophilic bands.
1
2
Above: Rabies. Negri body (in Purkinje cell of the cerebellum)
Bioterrorism in the United States: Anthrax Statistics (October 3 - November 28, 2001) • 23 cases of anthrax identified:
• 11 were confirmed as inhalational. With multidrug antibiotic Rx & supportive care, survival (6/11 or ~ 55%) was
much better than reported previously (15%).
• 12 cases (7 confirmed & 5 suspected) were cutaneous. o Cutaneous has better survival record.
Anthrax: Basics
• Caused by a sporeforming bacterium, Bacillus
anthracis
• Zoonotic disease in herbivores (sheep, goats, cattle) - follows ingestion of spores in soil
• Human infection by contact with anthrax-infected animals or animal products or through intentional exposure
• Three clinical forms - Cutaneous - Inhalational
- Gastrointestinal – rarest.
Test q: A 35M farmer develops several skin ulcers several days after butchering a cow. Gram stain shows large Gram-positive rods. The causative agent grows aerobically and produces spores. Diagnosis? Bacillus
anthracis. (Other choices: Clostridium difficile, Clostridium perfringens, Listeria monocytogenes, E. coli)
Cutaneous Anthrax:
Vesicle development, day 2 Eschar formation, day 4 Pathogenesis of Inhalational Anthrax:
• Inhalation of spores
• Incubation 2-3 days (range up to 60 days) • Phagocytosis of spores by alveolar macrophages • Migration of macrophages containing spores to
tracheobronchial lymph nodes • Multiplication of vegetative bacteria • Secretion of lethal & edema toxins
• Hemorrhagic mediastinitis & hematogenous dissemination • Meningitis in 50%; usually fatal in 3 to 5 days.
• Person to person transmission = no
Test q: Which of the following poses the lowest risk for person-to-person spread to physicians, nurses, or laboratorians? Anthrax (Other choices: Smallpox, Plague, Viral hemorrhagic fever)
Differential Diagnosis of Inhalational Anthrax: Mycoplasmal pneumonia Legionnaires’ Disease Psittacosis Tularemia Q fever Viral pneumonia
Histoplasmosis (fibrosing mediastinitis) Coccidioidomycosis
Wright-Giemsa stain of Bacillus anthracis in CSF:
Half of inhalational have CNS involvement – shows chains of rod-shaped bacteria in spinal fluid. Box-car shaped cells.
Caption from slide: Vesicle form – most likely form in which we would observe the bacilli of anthrax in a gram stain. The eschar would be less sensitive. Both lesions would be appropriate for cultures.
Patient with Anthrax: Initial Chest X-ray
Widened mediastinum = most important characteristic.
Inhalational Anthrax: B. anthracis:
Suppurative, Hemorrhagic Pneumonia in Monkey Gram stain demonstrating spores. Note Lung. Enlarged lymph nodes in mediastinum. spore location, subterminal…with no
SIGNIFICANT swelling of vegetative cell.
Laboratory Handling of Bacillus anthracis, BSL 2: • Anthrax vaccination is NOT required
• Laboratory coats and gloves must be worn • Safety glasses/shields are recommended
• Laboratory work performed in a biological safety cabinet • No hand/finger contact with mucosal surfaces
• Hand washing before leaving lab area
Bacillus anthracis Presumptive Identification:
• Nonmotile: B anthracis and B cereus var mycoides (and B. megaterium)
• Nonhemolytic, penicillin-zone (15-20 mm) and forms capsule: Presumptive B. anthracis Bioterrorism Agents, Laboratory Risk:
Agent BSL Laboratory Risk
B. anthracis 2 low
Y. pestis 2 medium
F. tularensis 2/3 high
Brucella spp. 2/3 high
Botulinum toxin 2 medium
Small pox 4 high
Viral hemorrhagic fever 4 high
Caption from slide (above): What is the historical risk of acquiring these agents while working in a laboratory? Review each agent.... Anthrax: no lab-associated cases since the late 1950’s, at which time the anthrax vaccine was introduced. USA prevalence: 3-5 cases reported in the last 10-15 yrs. Pestis: only 3 cases since the mid 1930’s. USA prevalence: 10-15 cases/yr. Tularensis and Brucella are the most frequently acquired lab-associated infections. Brucella being the most commonly reported lab-acquired bacterial infection, with tularensis as number 3. (typhoid is #2. TB#4, and hepatitis#5). Prevalence of tularemia: 150-200 cases/yr, Brucella: 100 cases/yr. There has been only 1 documented Bot Tox case. (100 cases of bot/yr). Smallpox: no cases for the last 20yr. And VHF….is not indigenous to USA.
Are you prepared?
B. anthracis
colony on SBA:
Note the edges are slightly undulate. Older colonies may produce large “projections” that have been described as “MEDUSA HEAD” colonies
Caption from slide: Many people are afraid to think about bioterrorism. They think it is too terrible to actually happen. Most experts, however, think it’s more a question of “when” than “if” because an attack could be relatively easy to execute. Even though a major attack could be devastating, advanced preparations could minimize the consequences. Therefore, it’s important to prepare. Biological Warfare is not new – there are many examples from history: 1346-47: Kaffa, Ukraine (formerly Crimea) Mongols (Tartars) catapulted plague infected corpses over the walls of the city. 1769: During the French and Indian War, British troops distributed blankets to “hostile” Native American tribes that had been used by small pox victims. 1940: The Japanese dropped wheat mixed with plague carrying fleas over Manchuria, China. Many health policy experts believe the United States is not well prepared now, but this training session is part of a nationwide preparation process. It is important for emergency room and primary care physicians to be informed about potential bioterrorist agents because exposed patients will likely first present symptoms to them. We will use case scenarios as a tool to aid in our discussion of various bioterrorist agents and the health care response.
Example Question (This was an old test q, see page 17)
Which of the following poses the lowest risk for person-to-person spread to physicians, nurses or laboratorians? A. Smallpox
B. Plague
C. Viral hemorrhagic fever D. Anthrax
Objectives: Following this lecture, the student should…
• Be able to discuss major factors that have contributed to emerging infectious diseases • Discuss the epidemiology of the emerging infections discussed in class
• Understand the pathology of the emerging infections discussed in class
• Describe the pathogenesis of selected infections emphasized in class (ie., C. difficile associated disease and community acquired MRSA infections)
• Know about the laboratory diagnosis of these infections
• Become aware of problems posed by a covert bioterrorist attack to the physician • Be able to discuss the diagnosis of anthrax
• Understand the relative risks posed by bioterrorist events to physicians nurses and laboratory personnel • Be motivated to prepare for how to deal with bioterrorism as an American Physician
Transfusion Medicine: Blood Bank 12/03/10
Objectives:
— Know the basic Blood Components — Know the expected benefits of transfusion — Know the risks of transfusion
Blood Volume:
Blood goes through two circulations – the heart is the center pump for both. First sends blood to lungs, where it releases CO2, picks up oxygen, the oxygenated blood comes back to the heart, it is pumped out, where it then distributes oxygen, nutrients, and hormones to cells of the body. It picks up waste products and CO2, delivers waste products to kidney and liver for detoxification and
elimination, before returning to the heart and starting the cycle all over again.
Hematocrit: Percent of blood occupied by RBCs. Hematocrit = RBC vol
(HCT) Total blood vol Ex: 40% = ? RBC vol = 2 liters
5 liters total blood An adult has ~ 2L of RBC,
~ 3L of plasma
Figure: Layers of Whole Blood Donation
All the blood that is transfused comes from non-paid volunteer donors. There are ~14 million blood donations in the US per year. Most common blood donation is 1 pint of whole blood (1 unit). This unit has a volume of ~500mL. If you spin it down, the RBCs are the most dense – layer at the bottom. The buffy coat is in the middle and includes white cells and platelets. The plasma layer is on top. From this donation, you can obtain 1 unit of RBCs for
transfusion, 1 unit of plasma for transfusion, but the number of platelets is only equal to ~1/5 or 1/6 of a total dose of platelets that would be needed for an adult transfusion.
Removal of White Cells (Leukoreduction) • Leukoreduction: All blood donations
have the white cells removed (>99.99%)
• Provide no benefit
• Predispose to febrile reactions and platelet refractoriness
• Harbor organisms (e.g. CMV, HTLV) • Theoretical risk of abnormal prion
transmission is reduced
• Theoretical risk of immunosuppression is reduced
Figure (above right) – Cryoprecipitate. One more product you can get from the unit of blood is cryoprecipitate. Made by taking a unit of frozen plasma, putting it in the fridge, and letting it thaw. Almost everything goes back into solution except for a little bit of white precipitate. Express off the plasma into a separate bag and send it to a manufacturing company to make albumin. The remainder – the precipitate with the tiny bit of plasma that remains – can be refrozen and stored up to a year.
Figure: Cytapheresis The blood comes out, mixes w/anticoagulant, goes into apheresis machine (continuous spinning cell separator). You program it and tell it which layer you want it to collect. That layer gets collected, and the rest gets returned to the donor. You can collect an entire dose of platelets (the amount you could get from 5 or 6 units of whole blood).
Where should blood components be stored?
Storage Temperature Maximum Storage Expiration of Product After Thawing
RBCs (Additive Solution) 1-6°C 42 days
Platelets (Pheresis) 20-24°C
5 days
Plasma Thawed (From FFP) <-18°C 1 year 1-6°C in 5 days
Cryoprecipitate <-18°C 1 year 20-24°Cin 4 hours
Frozen Red Cells <-65°C 10 years 1-6°C in 24 hours
Must keep platelets at room temperature. If refrigerated, they lose function and have to be thrown away. They need constant gentle agitation. Can use glycerol and freeze RBCs if they have some specific feature that you need. Test q: Platelets used for transfusion in the US should be stored w/agitation at: 20 to 24 degrees C.
Test q: Platelets can be used up to __ days after collection. 7 (The table above says “5 days”… the other choices on the test were: 1, 3, 30, 90) Above: Apheresis. All of the platelets that we currently transfuse (in this area) are collected by apheresis. The machine is a glorified centrifuge.
Red Blood Cells:
• Indication – Increase Oxygen-Carrying Capacity – Anemia
– Acute Blood Loss
1 unit RBC (Adult) increases Hgb 1 g/dL and Hct 3% (if the patient is not bleeding) • Limitations
– Not for treatment of nutritional deficiency – No viable platelets or granulocytes
Test q: A 70kg male is injured in an automobile accident w/severe blood loss. You wish to increase the patient’s hematocrit from 15% to 27%. You should transfuse how many RBC units? 4.
Until Hgb is below 10, you don’t need a transfusion. Between 6-10, depends on the patient. Massive Transfusion 2010:
• Minimize crystalloid resusitation
o For a person who is acutely bleeding, we used to use crystalloid (saline, Ringer’s lactate) immediately to keep a patient’s volume up, and if that isn’t sufficient, start giving RBCs, plasma, platelets as needed. This changed with the war in Iraq – it is much better if you do not give so much crystalloid up front • Prevent trauma induced coagulopathy by preventing:
- Hypothermia – keep them warm - Acidosis
- Dilution
• Transfuse- 1 RBC: 1FFP (Fresh Frozen Plasma): 1 Platelet Modifying Conditions:
1. Rate of blood volume depletion
2. Demands on O2 delivery – will they be laying in the
hospital? Sedentary? 3. Cardiopulmonary status 4. Underlying disease
Figure: RBC phenotypes and antibodies
There are all kinds of antigens on RBCs. The most important are A antigens, B antigens, and the lack of them – group O. The antigens are everywhere – tissues, RBCs, environment, etc. If you are Group O and do not have A and B antigen on tissues or RBCs, you will still come in contact w/them in the environment. So even if you have never been transfused, you will automatically have made anti-A and anti-B. If you have both AB, you will not make any of these.
The blood group O can give RBCs to anyone – universal donors. The recipient who is AB can receive RBCs from anyone.
Test q: In blood transfusion, the universal “donor” and universal “recipient” are __ respectively: O; AB.
The next most important antigen is the D antigen (one of the Rh antigens), but it is not like the ABO’s because it is only on RBCs.
If you are Rh negative (you lack the D antigen and you have not been exposed to any RBCs w/the D antigen), you will not have made anti-D. Most of the population does have the D antigen – they are Rh+. This is of greatest importance in women of child-bearing age, since anti-D can cause hemolytic disease in the newborn. You do not want to expose these women to D+ RBCs.
Factors Affecting Posttransfusion Platelet Increment: • Fever
• Sepsis
• Hypersplenism
• Consumptive Coagulopathy (DIC) • Platelet Antibody
– Alloimmune – Autoimmune
Frozen Plasma:
• Frozen Plasma is a source of clotting factors, with half-lives in vivo of between 6 hours & 3 days.
• Available in 2 forms:
- 250 mL recovered from regular donations - 500 mL from apheresis donation
• 30 minutes required for thawing
Thawed Plasma ~Fresh Frozen Plasma (FFP): • Indication:
– Multiple Coagulation Factor Deficiencies • Liver Disease
• DIC
• Massive Hemorrhage
– Factor Deficiency not available as concentrate or in cryoprecipitate
• 1mL FFP contains ~1unit of each coagulation factor
• Starting Dose 10-15 mL/Kg • Cautions:
- Not a concentrate (~200 mL/Bag) - Not for volume or protein replacement.
Figure (left): Platelets are important for hemostasis. The usual platelet count is 150k-400k. The lifespan of
platelets in circulation is 7-10 days. When you have damage to the endothelium of a vessel, the collagen becomes exposed. When the platelets come in contact with the collagen, they undergo activation, aggregation, and the whole coagulation cascade process starts. Figure (right): If you have too few functional platelets, you can develop microvascular hemorrhages (little petechiae, shown here) or mucosal bleeding.
Guidelines for Platelet Transfusion Greatest concern – spontaneously developing
hemorrhage in the brain or in the eye. When the platelet count gets very low (less than 10,000), a dose of
platelets will be given to prevent spontaneous
hemorrhage (even if the patient isn’t bleeding). If they are going to go to surgery, if they are having a massive transfusion, if they are bleeding, etc., they need to maintain their count at ~50,000. If the platelets aren’t functional (qualitative platelet defect), no matter how many they have, they need a dose of platelets before having a procedure done.
Test q: Platelet transfusion is recommended to prevent spontaneous intracranial bleed if the platelet count falls below: 10,000/mm3.
These issues can cause the increase to not be as large as expected. After giving platelets (10 min-60 min later), make sure you got the rise that you expected. If not (and if you don’t have any of these reasons), call the blood bank because patient may be developing antibodies to platelets. May be to specific antigens on the platelet or HLA antigens on the platelet.
Frozen Plasma – Dose and Infusion:
• Dose is 10-15 mL/Kg, or 750-1000 mL for average sized adult • Infusion time 30-120 minutes
• Should be ABO compatible
• Check INR/PT/PTT after infusion to confirm outcome
For plasma, everything is opposite from RBCs. For plasma, the universal recipient is Group O – can be transfused w/plasma from anyone. An AB patient can only receive AB plasma. An AB donor can give plasma to anyone.
Cryoprecipitate:
Constituents Amount
Factor VIII 80 – 120 units/Bag
Fibrinogen
Fibrinogen 150 – 250 mg/Bag
von Willebrand Factor 40 – 70% of Original FFP
Factor XIII 20-30% of Original FFP
Concentrate from FFP – only contains these factors. Given to increase fibrinogen level – want it to be above 100. Transfuse Irradiated Blood Components to Prevent Graft-Versus-Host-Disease:
• Disease that arises as a consequence of reaction of the donor (= graft) against the recipient (= host). • This reaction is caused by T-lymphocytes from the donor.
o There are no T lymphocytes left in the plasma and cryoprecipitate, they are in the RBCs and platelets.
Figure: GVHD
Transfuse lymphocytes, and they recognize the host tissue as foreign start attacking it. If the recipient is immunocompetent, their WBCs attack the transfused lymphocytes and there is no GVHD. If the patient is immunodeficient, there are no recipient lymphocytes to attack the transfused WBCs, so they just continue on.
Does not happen in AIDS patients because all lymphocytes are removed due to the virus – host and graft lymphocytes. Irradiation:
Cellular components shall be irradiated when:
1. A patient is identified as being at risk for transfusion-associated graft-vs-host disease: • patients receiving intensive chemotherapy; BMT
• Infants receiving intrauterine transfusion
• patients with congenital immune-deficiency syndrome 2. The donor of the component is a blood relative of the recipient.
3. The donor is selected for HLA compatibility, by typing or crossmatching.
Test q: Which of the following statements regarding modified blood components is true? Irradiating cellular components decreases the risk of GVHD.
Test q: To prevent graft vs. host disease, what type of RBCs are used: Irradiated RBCs. Per year in the US:
• 20 x 106 Transfusions • 200,000 adverse reactions • 50 transfusion-related fatalities
Above: If the donor is homozygous for an HLA haplotype (here, “a”) and they are being transfused to someone who might share one but not both with them (ab), worry about GVHD.
Table 6-2. Current Estimated Viral Window-Period Risk in American Red Cross Repeat Blood Donor Population* Virus Screening Markers Window Period (Days) Risk (Rate Infectious Donations)
HIV-1/2 Anti-HIV and p24 16 1:1,468,000
HIV-1/2 Anti-HIV and NAT 11 1:2,135,000
HTLV-I/II Anti-HTLV 51 1:2,993,000
HCV Anti-HCV and NAT 10 1:1,935,000
HBV HBsAg 59 1:205,000
Test q: The risk for acquiring HIV-1 from a transfusion in the US is: 1:2,000,000 A Patient’s Specimen must have:
• Patient identifiers • Phlebotomist signature • +/- witness signature • Date and time collected*
*A patient’s specimen can be used for 3 days Acute Hemolytic Transfusion Reactions:
• The root cause of ABO incompatible reactions is CLERICAL ERROR
• Test q: The number one cause of hemolytic transfusion in the US is: Clerical error.
• Half are due to administration of properly labeled blood to the wrong patient
• Most of the others are due to improper labeling of pre-transfusion blood samples or test result recording errors – Identifiers on wrist band
– Identifiers on specimen label – Identifiers on requisition – All Identical
Incidence:
• About 1 in 40,000 red cell transfusions include an ABO incompatible unit
• <10% of these are fatal (current estimate 1 in 1.8 million) • >50% no morbidity
• About 1 in 14,000 units given to the wrong patient are fortuitously compatible
• Risk of death correlates with amount transfused • 13% of severe morbidities due to non-ABO antibodies Clinical Presentation:
• Common:
- Hemoglobinuria
- Fever and chills – main symptoms • Other
- Pain in infusion vein - Lumbar pain
- Dyspnea and hypotension - Renal failure
- DIC
• Fever may be only presenting sign
• Under anesthesia only objective signs (e.g. shock, DIC, hemoglobinuria) will be apparent
Acute Hemolytic Transfusion Reactions (cont’d): • Management:
- STOP the transfusion - Notify the Blood Bank
- Send fresh blood sample and residual blood product to Blood Bank for re-testing
- Supportive care:
Blood pressure support Inotropes
Good urine ouput, avoiding fluid overload Monitor for hyperkalemia
• Treat bleeding due to DIC with platelets, plasma and cryoprecipitate according to guidelines
Figure: Febrile non-hemolytic and cutaneous allergic reactions are most common adverse reactions
Febrile Non-hemolytic Transfusion Reactions: • Clinical Presentation:
- Fever during or soon after transfusion - May be associated with:
Chills Rigors Nausea Vomiting Hypotension
• Note: Occasionally fever is not present • Management:
- Acetaminophen (Tylenol) 325-650 mG orally
- For severe rigors, Meperidine (Demerol) may be used
• Prevention:
- Routine premedication with acetaminophen or antihistamines probably not effective - Drugs to consider for patients with repeated
FNHTR Acetaminophen Corticosteroids Meperidine - Component manipulation: Fresh component Plasma removal
Washed red cells (washed platelets lose function)
Reactions Commonly Presenting with Fever: • Fever is usually a feature of:
- Bacterial contamination or sepsis - Acute hemolytic transfusion reaction - Febrile non-hemolytic transfusion reaction
Bacterial Contamination: • Sources of organisms:
- Skin commensals from the donor – usually gram+ organisms - Unrecognized bacteremia in the donor
- Contamination from the environment (e.g. thawing frozen plasma - Gram negative organisms tend to cause more severe effects than
Gram positive organisms – can be fatal
Figure (left): Usually there is not a significant level of bacteria present to cause symptoms until unit is more than 21 days old.
Figure (right): Most common symptoms – fever and chills.
Above (right): In 2002, reports of transfusion-associated fatalities started going up because of increased awareness of the TRALI reaction. Since 2002, the main cause of transfusion-related fatality has been TRALI reaction. Percentage has now leveled off, but is not still down at ~50 anymore.
Test q: Failure due to transfusion is now most commonly associated with: Transfusion related acute lung injury (TRALI) reaction. Transfusion Related Acute Lung Injury (TRALI):
• Syndrome of acute respiratory distress with - Hypoxia
- Bilateral pulmonary edema
- No evidence of congestive heart failure • Within 6 hours of transfusion
• Any labile component or rarely IVIG • Usually resolves in 24-72 hours • Mechanism of TRALI:
- HLA or granulocyte antibodies in donor plasma from immunization
In pregnancy
By previous transfusion
- Biologically active lipids in donor plasma
- Rarely recipient antibodies to transfused white cells - Release of cytokines in lungs from damaged white cells
Some of the cases appear to be due to antibodies in the product to WBC antigens in the recipient. Women are more likely to have these antibodies if they have been pregnant, so pretty much all transfused plasma comes from men. Have seen decrease in episodes of this reaction.
• Management of TRALI: - Supportive care
- Mechanical ventilation required in about 75% of cases - Diuretics and steroids probably not useful
• Prevention:
- Accurate diagnosis and reporting
- Testing of donor(s) to identify the particular implicated donor - Deferral of implicated donors
Transfusion Associated Circulatory Overload (TACO): • Incidence:
- About 1 in 700 transfusion episodes
- In older peri-operatve patients TACO is commoner, about 1 in 100 transfusions
- Both older patients and infants with anemia and normal blood volumes are at greater risk • Presentation:
- Dyspnea - Orthopnea
- Engorged neck veins
- Cyanosis - Tachycardia - Hypertension
Similar symptoms to TRALI, but in this case, there is evidence of circulatory overload. Figure Bilateral plumonary edema (white-out). Most patients need mechanical ventilation.
Figure: TACO vs. TRALI
If you see oxygen saturation levels less than 90%, CXR shows white-out, and symptoms start within 6hr of transfusion, could either be TACO or TRALI. Patient will have less protein in the edema fluid with TACO. The BNP (beta natriuretic protein – associated with heart failure) – will be elevated w/TACO. In TRALI, heart will look normal.
Above: Allergic reaction – extensive hives. Allergic reactions can be minor or major (anaphylaxis). Allergic Reactions (Anaphylaxis): Anaphylactic reactions are rare but may be life-threatening
Incidence: 1 in 40,000 transfusion episodes Etiology:
- usually (80%) unexplained - Anti IgA in an IgA deficient patient
- Antibodies to polymorphic (genetic variable) donor proteins (e.g. IgG) - Transfusion of an allergen in the donor to sensitized patient
- Passive transfer of IgE • Clinical Presentation:
- Begins 1-45 minutes after start (quick!) - Cutaneous reaction (hives, flushing)
- Airway obstruction, dyspnea, wheezing, stridor - Acute anxiety
- Hypotension
- Nausea and vomiting
• Management of Acute Anaphylactic Reaction: - STOP the transfusion
- Prompt administration of epinephrine, IV diphenhydramine (“benadryl”) 25-50 mG, corticosteroids
- Epinephrine should be available wherever transfusion is carried out • Prevention: Product modification where sensitization is known
Use IgA deficient product from CBS/HQ Washed RBC – 6 washes of 500 mL each
Figure: Summary – Signs/Symptoms of Acute Transfusion Reactions
Shortness of Breath (SOB) – may be with all of them, but will not be as significant w/bacterial contamination.
Hypotension – seen in everything except circulatory overload (usually have hypertension w/that)
Only bacterial contamination leads to DIC.
“Blood transfusion is like marriage; it should not be entered upon lightly, unadvisedly, or wantonly, or more often than is absolutely necessary.”
Pathology Notes – What to Review 12/03/10 ATRA in Treating APL:
See cells at the bottom of this figure – these cells, with exposure to Vitamin A, will mature to bands and neutrophils. Vitamin A is required for maturation of a lot of different cell types. People get infections because of lack of maturation of pulmonary cells. Get renal stones because of lack of maturation in the kidney. Especially in animals – not so much in people – females can be sterile because fallopian tubes don’t develop cilia and don’t mature. Treatment application of that, discussed in APL case.
Treatment of APML:
• ATRA + anthracycline (daunorubicin or idarubicin) is the standard induction regimen
o Two-fold treatment – if you just give Vitamin A, you never get rid of the abnormal stem cell that’s causing the problem. Need the Vitamin A and also need the poison – daunorubicin is common – to kill the stem cell. Poison kills the stem cell, and retinoic acid allows the promyelocytes to mature.
• ATRA then used as maintenance therapy once complete for 1 year • Over 70% long term survivals!!
o Of all the AMLs, this is the one we are most successful at treating. Unfortunately, is not the most common AML. In a healthy young adult w/APL, cure rate is 90-95%.
Treatment Duration:
• Neutrophil count is the single most important determinant for people with infection. o Must keep treating a person w/antibiotics until neutrophil count improves. • Risk of infection decreases when ANC > 500cells/mm3
• Generally discontinued when ANC > 500cells/mm3 x 2 days
o Magic number for neutrophil count is 500. Under 500 is severely neutropenic. To stop antibiotics, want them to be above 500.
• No identifiable infectious despite febrile state What is Neutropenia?
• Normal Range: 1,800-7,800 neutrophils/mm3
• Nadir: Lowest point of WBC following chemotherapy - (usually occurs at 10-14 days) • Absolute Neutrophil Count (ANC): ANC= WBC X [(%Segs/100) + (%Bands/100)] • Must take into account neutrophils and bands.
What are the Pathogens?
• Gram Positive [G(+)] – most common
• Gram Negative [G(-)] – most deadly bacteria are G(-) • Fungi
• Virus • Protozoa
As neutropenia goes on, need to worry about fungal infections – Aspergillus and Candida. Also begin to worry about them if all your bacterial work-ups and cultures are negative.
