Micro Cheat Sheet #3

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Micro Cheat Sheet #3

(PASS Videos)

- Shigella

o Causes gastroenteritis associated with daycare outbreaks o Most immunogenic bacteria

o Has an exotoxin (shiga toxin) which causes seizures o S. sonneii: common in the US

o S. dysentery: common outside the US

- Salmonella

o Encapsulated

o Loves to attack people with sickle cell anemia (causes osteomyelitis) o Causes gastroenteritis associated with raw chicken or raw eggs o Runs and hides in the gallbladder if you treat it with antibiotics

 Can precipitate cholecystitis o Causes a biotin deficiency

o Causes monocytosis

o S. enteritidis: most common strain in US o S. dysentery: common outside the US o S. typhi

 Cause of typhoid fever

 Traid: fever, rose spots, and intestinal fire (stomach feels like it is burning)

 Causes heart block

 Associated with contaminated water  Tx: ciprofloxacin

- Bordatella

o B. pertussis

 Causes whooping cough

 Prodromal stage – fever, runny nose

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 Paroxysmal stage – cough

 Has an exotoxin that ADP-ribosylates Gi subunit of the G-protein  Exotoxin is intracellular  kills cells

 High cAMP increases mucus in the lungs

 Causes extreme lymphocytosis ( should be PMN’s but lymphocytes instead)

 MCC of death was suffocation  Vaccination - DtaP

 Diagnosis: ELIZA on nasopharyngeal washings

 TX: erythromycin; also treat close contacts (>25hrs) with erythromycin

- Pasturella

o P. multocida

 Causes cellulitis associated with an infected cat or dog bite  Found in the saliva of cats and dogs

 Mix up with Bartonella henselae – cat scratch – Bart Simpson  Tx: Amoxacillin

- Brucella

o Causes undulating fever (5-7 fever spikes a day)

o Seen primarily in veterinarians and farmers who deliver animals o Attaches to placenta

- Bartonella

o B. henselae  Silver stain

 H. pylori, B. henselae, and Legionella  Causes cat scratch fever

 Carried by kittens

- Francisella

o F. Tularensis

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 Transmitted by rabbits (90%) and deer (10%) Tularemia cause  Tx: streptomycin

 Cannot give to a pregnant woman  teratogenic

- Vibrio

o V. cholera

 Curved rod

 Has an exotoxin that ADP-ribosylates

Gs

and elevates cAMP  “Rice water” diarrhea (also ETEC)

o V. parahemolyticus

 Diarrhea associated with raw fish o V. vulnificus

 Diarrhea associated with raw oysters - Campylobacter Jejunii

o Curved rod

o Attackes the jejunum; causing copious blood diarrhea o Causes diarrhea associated with raw chickens or raw eggs o Tx: Erythromycin

- Yersinia

o Likes the Southwest o Vector: prairie dog o Y. Pestis

 Bubonic plague  Pneumonic plague o Y. Enterocolitica

 Likes to attack the ileum causing ileitis or mesenteric adenitis (mimic’s appendicitis in symptoms

 Causes Reiter’s syndrome- any post infection arthritis o HLA-B27 diseases

 Reiter’s syndrome-any post infection arthritis  Ankylosing spondilytis-shoeberg test, bamboo spine  Psoriasis-silver plaque on extensor surfaces

 Tx: methaltrexate, and UV light (sunlight)  cells don’t rapidly divide

 Psoriasis w/o arthritis- HLA B13 - Atypicals

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o have no cell wall

o granulomatous inflammation

o covered by Quinalones, Macrolides, and tectracyclines

o causes interstitial pneumonia symptoms out of proportion to physical findings  walking pneumonia labs do not coincide with what you can see

 consider: if adult: Chlamydia Pneumonia  Teen: Mycoplasma pneumonia

- Chlamydia

o Parasites: depend on the host for ATP o Eosinophilia

o Has two forms:

 Elementary body (infectious)  Reticulate body (dormant form) o Granulomatous inflammation

o C. Trachomatis

 Causes trachoma: Mcc #1 of neonatal blindness in the world

 -trachoma: destruction of the cornea from scarring

 -Prevention: apply erythromycin to eyes  Mcc of lymphogranuloma venereum

 Mcc of STDs (90% are asymptomatic)  Mcc of infertility in WOMEN

 Mcc of ectopic pregnancy (from scarring)

 No cilia to move egg along

 Most common location for ectopic pregnancy is ampulla

 Hcg is low  Diagnosis:

 ELIZA with all pap smears  Tx: one-dose :azithromycin

 Old Tx: doxycycline for 7 days o C. Pneumonia

 Mcc of atypical pneumonia (0-2 mo)  Eosinophilia

 Interstitial pneumonia

 Symptoms out of proportion to physical findings

 Steccato coughing (*a—hoo—a—hoo* hard time breathing)

 Found to be connected to Alzheimer’s disease and coronary artery disease (CAD)

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o IF PT PRESENTS with Walking Pneumonia:  Adults: choose Chlamydia

 Teens: mycoplasm o C. Psitacii

 KEY: Pet shop

 Associated with parrots and parakeets

 Causes interstitial pneumonia or nonbacterial endocarditis - Mycoplasma

o No cell wall

o NO epithelial lining o Look like a jellyfish

o Mcc of atypical pneumonia from ages 10 to 30 o Cold agglutinins (cryoglobulinemia)

 IgM Abs attracted to RBCs cause them to clump o Causes “walking pneumonia”

o Interstitial pneumonia with symptoms out of proportion to physical findings o M. Hominis

 An occasional cause of vaginitis - Legionella Penumonphilia

o Mcc of atypical pneumonia age 40yrs o Interstitial pneumonia

o Silver stain

 H. pylori, Bartonella Hensli, and Legionella

o Grows on CYAE (charcoal, Yeast agar) “3 sisters Ella in the Cysteine chapel” o Likes standing water on heating and air conditioning systems (**vegetable and

fruit sprayersmists)

o Causes high rise building syndrome or hotel/motel syndrome o Pontiac Fever: fever and nonspecific symptoms

o Legionnaire’s disease: full blown pneumonia o Granulomatous inflammation

o Causes Heart Block

 First degree: fixed prolonged PR interval

 Tx: do nothing, asymptomatic  Second degree:

 Mobitz 1: progressively prolonged PR interval until a QRS complex is dropped

o Winki Bauck Mcc from DRUGS o D/c offending drug

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 Mobitz 2: normal PR interval; erratic dropping of QRS complexes o Tx: D/c the drug and if needed PACE THEM

 Third degree: NO relationship between P waves and QRS complexes

 Tx: put in a permanent pacemaker  INFECTIONS THAT CAUSE:

 Legionella  Lyme  Diptheria  Chaga’s  Typhoid fever - Ureoplasma Urolyticum

o An occasional cause of vaginitis

o Has NO cell wall or epithelial lining like mycoplasma o Urease (+)

o Case: little girl who has this; assume sexual abuse FUNGI

- Like warmth and moisture (skin folds, groin, axilla, vagina) - Like to eat sugar- DIABETICS MOST COMMON

- To prevent fungal infections, keep cool and dry

- Have a unique lipid in their membrane called ergesterol - Antifungals:

o Bind to ergestrol

 Amphotericin B- IV for systemic fungal infections

 Get confused with cholesterol

 Pokes holes in your cells—releasing K+

 EKG changes: Peaked T waves

 True hyperkalemia

 Nystatin- PO wash, does not cross intact membrane

 Mycostatin- topical: athletes foot, jock itch, oral thrush, ring worms, vaginitis

 Miconazole

 Clotrimazole: topical: inhibits P450 of fungus  Tolnaftate: over the counter: spray or topical cream

 Terbenafine: Lamisil for Nail infections (more than 1 nail affected otherwise will take the 1 nail off) @5:30

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 Flucytosine (5FC)-inhiits mitosis (acts like pyramadine analog) inhibits the DNA fungal synthesis

 Inhibits erg sterol synthesis

 Fluconazole- best CNS penetration (cross BBB)

 Itraconazole

 Ketoconazole- inhibits the P450s, blocks 5α reductase more effective

 Inhibits microtubules

 Griseofulvin o Superficial Fungi infections

 Piedre- blk balls on the hair shaft

 Tx: cut hair

 Microsporum Beigeii- white balls on the hair shafter