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Bleeding Disorders

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Chapter Six Haematology

MAP 6.3 Bleeding Disorders

Map 6.3 Bleeding Disorders

Haematology

99

BERNARD–SOULIER SYNDROME What is Bernard–Soulier syndrome?

This is an autosomal recessive bleeding disorder.

Causes

This is a hereditary condition that leads to deficiency of glycoprotein (Gp) Ib.

Investigations

- Bleeding time, normal or ¯ platelet count.

Treatment

Conservative: patient education.

Medical:

Desmopressin may decrease bleeding time.

Recombinant activated factor VII.

CLOT FORMATION

This consists of 4 steps. Defects in steps 2–4 may lead to a bleeding disorder.

1 Vessel constriction.

2 Platelet adhesion and aggregation: Glanzmann’s thrombasthenia, von Willebrand disease, Bernard–Soulier syndrome.

3 Blood coagulation: haemophilia. 4 Fibrinolysis: antiplasmin deficiency.

HAEMOPHILIA What is haemophilia?

This is an inherited condition that impairs the body’s ability to coagulate the blood.

Causes

This is a hereditary condition. There are two forms of haemophilia:

Type A: lack of factor VIII.

Type B: lack of factor IX.

Investigations

Normal prothrombin time, - partial thromboplastin time.

Treatment

Conservative: patient education. Avoid aspirin, NSAIDs, heparin and warfarin.

Medical: replace deficient clotting factor with regular infusions.

GLANZMANN’S THROMBASTHENIA What is Glanzmann’s thrombasthenia?

This is a rare autosomal recessive or acquired autoimmune condition in which platelets are deficient of GpIIb/IIIa. GpIIb/IIIa binds fibrinogen.

Causes

Disease of hereditary or acquired autoimmune cause.

Investigations

- Bleeding time.

Treatment

Conservative: patient education. Avoid aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs).

Medical:

Desmopressin.

Recombinant activated factor VII.

VON WILLEBRAND DISEASE What is von Willebrand disease?

This is the most common hereditary coagulation disorder, which involves a defect in von Willebrand factor (VWF). The function of von Willebrand factor is to bind GpIb receptor on platelets to subendothelial collagen.

Causes

Hereditary condition. There are many different types of von Willebrand disease, but the most common are type 1, type 2, type 3 and type Normandy.

Investigations

- Activated partial thromboplastin time, - Bleeding time, normal prothrombin time, ¯ VWF antigen, ¯ factor VIIIc.

Treatment

Conservative: patient education. Avoid aspirin and NSAIDs.

Medical: desmopressin may be useful, but is not helpful in type 3 von Willebrand disease.

VITAMIN K INSUFFICIENCY What is vitamin K insuffiency?

This avitaminosis occurs when there is decreased vitamin K1 or vitamin K2 or both. This results in:

¯ Synthesis of factors II, VII, IX and X.

¯ Synthesis of proteins C and S.

Causes

Drugs, e.g. warfarin.

Malnutrition.

Malabsorption.

Alcoholism.

Cystic fibrosis.

Chronic kidney injury.

Cholestatic disease.

Investigations

- Prothrombin time, normal or - partial thromboplastin time.

Treatment

Conservative – patient education. Dietary advice about food rich in vitamin K

Medical – treat cause. Vitamin K supplements.

MAP 6.3 Bleeding Disorders

Map 6.3 Bleeding Disorders

Chapter_06.indd 99

Haematology

100 Map 6.4 Leukaemia

Causes

Neoplasm Cause

ALL Possibly a genetic susceptibility coupled with an environmental trigger

Exact cause unknown

Comment

Commonest cancer in children Often spreads to central nervous system Associations – DIP:

Down’s syndrome

Ionising radiation

Pregnancy

Usually affects adults over 60 years old Affects B lymphocytes

Positive ZAP-70 marker is associated with a worse prognosis

CLL

AML Exact cause unknown Risk factors include:

Myeloproliferative disease

Alkylating agents

Ionising radiation exposure

Down’s syndrome

Commonest leukaemia in adults Rapidly progressing

Auer rods on microscopy are diagnostic

CML Exact cause unknown Risk factor: ionising radiation exposure

Usually affects males 40–60 years old 80% associated with the Philadelphia chromosome t[9;22], forming bcr-abl fusion gene

AML Bone marrow failure Malaise

Weight loss Night sweats CML Bone marrow failure

Hepatosplenomegaly Malaise

Weight loss Night sweats

Signs and symptoms

Neoplasm Clinical features

ALL Bone marrow failure Bruising Shortness of breath Purpura Malaise Weight loss Night sweats Asymptomatic Bone marrow failure Nontender lymphadenopathy Hepatosplenomegaly Malaise Weight loss Night sweats CLL What is leukaemia?

This is a rare neoplasm of the blood or bone marrow. It is classified into lymphoid and myeloid neoplasms that may present chronically or acutely. These 4 classifications are:

1 Acute lymphoblastic leukaemia (ALL). 2 Chronic lymphocytic leukaemia (CLL). 3 Acute myeloid leukaemia (AML). 4 Chronic myeloid leukaemia (CML).

Treatment Treatment ALL Conservative CLL Chlorambucil Fludarabine Rituximab Prednisolone Cyclophosphamide Patient education; refer to Macmillan nurses

Medical Induce remission and maintenance To induce remission:

Dexamethasone

Vincristine

Anthracycline antibiotics

Cyclophosphamide Maintenance:

Methotrexate

Mercaptopurine

Cytarabine

Hydrocortisone AML Patients <60 years:

chemotherapy with an anthracycline and cytarabine or methotrexate

Patients >60 years:

palliative anthracycline, cytarabine or mitoxantrone

If M3 type AML, i.e. acute promyelocytic leukaemia (APML), then add all-trans retinoic acid to the therapeutic regime

CML

Imatinib

Patients <60 years may be considered for allogeneic stem cell transplantation Other treatments include alpha-interferon, vincristine, prednisolone, cytarabine and daunorubicin Investigations

Bloods: FBC, WCC, platelets, U&Es, LFTs, ESR, CRP.

Bone marrow biopsy, lymph node biopsy.

Radiology: X-ray, ultrasound scan, CT scan, MRI.

AML and ALL are classified using the French–American–British (FAB) classification.

Complications

Death.

Increased risk of infection.

Haemorrhage: pulmonary, intracranial.

Depression.

Complication of chemotherapy. MAP 6.4 Leukaemia 08/12/14 6:16 PM

Haematology

101 Map 6.4 Leukaemia

Causes

Neoplasm Cause

ALL Possibly a genetic susceptibility coupled with an environmental trigger

Exact cause unknown

Comment

Commonest cancer in children Often spreads to central nervous system Associations – DIP:

Down’s syndrome

Ionising radiation

Pregnancy

Usually affects adults over 60 years old Affects B lymphocytes

Positive ZAP-70 marker is associated with a worse prognosis

CLL

AML Exact cause unknown Risk factors include:

Myeloproliferative disease

Alkylating agents

Ionising radiation exposure

Down’s syndrome

Commonest leukaemia in adults Rapidly progressing

Auer rods on microscopy are diagnostic

CML Exact cause unknown Risk factor: ionising radiation exposure

Usually affects males 40–60 years old 80% associated with the Philadelphia chromosome t[9;22], forming bcr-abl fusion gene

AML Bone marrow failure Malaise

Weight loss Night sweats CML Bone marrow failure

Hepatosplenomegaly Malaise

Weight loss Night sweats

Signs and symptoms

Neoplasm Clinical features

ALL Bone marrow failure Bruising Shortness of breath Purpura Malaise Weight loss Night sweats Asymptomatic Bone marrow failure Nontender lymphadenopathy Hepatosplenomegaly Malaise Weight loss Night sweats CLL What is leukaemia?

This is a rare neoplasm of the blood or bone marrow. It is classified into lymphoid and myeloid neoplasms that may present chronically or acutely. These 4 classifications are:

1 Acute lymphoblastic leukaemia (ALL). 2 Chronic lymphocytic leukaemia (CLL). 3 Acute myeloid leukaemia (AML). 4 Chronic myeloid leukaemia (CML).

Treatment Treatment ALL Conservative CLL Chlorambucil Fludarabine Rituximab Prednisolone Cyclophosphamide Patient education; refer to Macmillan nurses

Medical Induce remission and maintenance To induce remission:

Dexamethasone

Vincristine

Anthracycline antibiotics

Cyclophosphamide Maintenance:

Methotrexate

Mercaptopurine

Cytarabine

Hydrocortisone AML Patients <60 years:

chemotherapy with an anthracycline and cytarabine or methotrexate

Patients >60 years:

palliative anthracycline, cytarabine or mitoxantrone

If M3 type AML, i.e. acute promyelocytic leukaemia (APML), then add all-trans retinoic acid to the therapeutic regime

CML

Imatinib

Patients <60 years may be considered for allogeneic stem cell transplantation Other treatments include alpha-interferon, vincristine, prednisolone, cytarabine and daunorubicin Investigations

Bloods: FBC, WCC, platelets, U&Es, LFTs, ESR, CRP.

Bone marrow biopsy, lymph node biopsy.

Radiology: X-ray, ultrasound scan, CT scan, MRI.

AML and ALL are classified using the French–American–British (FAB) classification.

Complications

Death.

Increased risk of infection.

Haemorrhage: pulmonary, intracranial.

Depression.

Complication of chemotherapy. MAP 6.4 Leukaemia Chapter_06.indd 101 08/12/14 6:16 PM

Haematology

102 Map 6.5 Hodgkin’s vs. Non-Hodgkin’s Lymphoma

HODGKIN’S LYMPHOMA

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