Clinical questions - Hematology

Question 1

Most likely cause of microcytic anemia with neurologic symptoms

Answer 1

Lead poisoning - neurologic symptoms may include wrist/foot drop, confusion, headache

Question 2

Most likely cause of Megaloblastic anemia with neurological symptoms

Answer 2

B12 deficiency - peripheral neuropathy and ataxia

Question 3

Most likely cause of anemia in a patient who eats ice

Answer 3

Iron deficiency

Question 4

Most likely cause of anemia that develops after taking a sulfa drug

Answer 4

G6PD deficiency

Question 5

Most likely cause of anemia in a patient with rheumatoid arthritis

Answer 5

Anemia of chronic disease

Question 6

Hemolytic uremic syndrome: presentation, lab findings, cause, treatment

Answer 6

Presentation: Vague abdominal pain, occasional vomiting, bloody diarrhea, dark urine, jaundice - typically child.

Lab: 
Low platelets
Elevated LDH, indirect bilirubin, low haptoglobin - signs of hemolysis
Negative coombs test (not autoimmune)
elevated creatinine

EHEC O157:H7 -> microangiopathic hemolytic anemia, thrombocytopenia, AKI

Tx: Supportive

• pRBC, plts transfusions
• dialysis
• plasma exchange
• Eculizumab

Question 7

Polycythemia vera: presentation, cause, dx, treatment

Answer 7

Presentation: intermittent stinging or burning pain in the hands sometimes associated with redness (erythromyalgia), intense pruritis when taking a warm bath

Cause: monoclonal proliferation of RBCs - not a malignancy

Dx:
R/o hypoxemia
High Hgb and Plt
Slightly low EPO
BMBx

Tx:
Phlebotomy
hydroxyurea
Low-dose aspirin for erythromyalgia
antihistamines for pruritis

Question 8

G6PD deficiency, presentation, diagnosis, provoking causes

Answer 8

Presentation: profound fatigue, darkening of urine after being exposed to a provoking agent which causes oxidative damage -> hemolytic anemia

Diagnosis:

• Normocytic anemia
• Hemolysis on labs - elevated LDH and t bili, low haptoglobin
• Peripheral smear: Heinz bodies and degmacytes “bite cells”

Provoking causes:

• antimalarials: Primaquine, Chloroquine
• Nitrofurantoin
• Sulfonamides (bactrim)
• Dapsone
• Isoniazid
• high doses of ibu or asa (safe at usual doses)
• Fava beans

Question 9

Multiple myeloma: presentation, diagnosis

Answer 9

Presentation:
Weakness, fatigue, increased back pain, fractures

Diagnosis:
Labs:  Anemia, hypercalcemia, increased BUN and creatinine
SPEP: Monoclonal Ab spike - "M" spike
UPEP: Bence-Jones proteins
BMBx: increased plasma cells

Question 10

Immune thrombocytopenic purpura: presentation, diagnosis, treatment

Answer 10

Presentation: recurrent gingival bleeding, nosebleeds, painless non-pruritic rash over lower extremities (petechiae)

Dx:
Low platelet count - below 50K
Normal PT/PTT

Tx:
Asx: no treatment
Sxs: PO GLUCOCORTICOIDS, plts, IVIG -> -> -> splenectomy

Question 11

Inherited hypercoagulable states

Answer 11

Factor V Leiden
Prothrombin G20210A mutation
Protein C or S deficiency
Antithrombin deficiency

2 or more spontaneous thrombus requires long term WARFARIN, with INR goal of 2-3

Question 12

What is the next step of working up a patient with hypochromic, microcytic anemia, Hgb 9.4, normal iron studies

Answer 12

hemoglobin electrophoresis to w/u thalassemias

Question 13

Von Willebrand disease: presentation, diagnosis, treatment

Answer 13

Presentation: prolonged bleeding from minor source, easy bruising, nose bleeds, heading menstrual bleeding

Dx:
normal Plts, normal PT
increased PTT
Bleeding time elevated
Ristocetin cofactor activity markedly reduced

Tx:
Desmopressin (DDAVP) - intranasal or IV
-stimulates release of stored VWF from endothelin cells
Concentrated VWF

Question 14

What is being tested with PT, PTT, bleeding time?

Answer 14

Coagulation cascade:
PT - short arm, factor 7 and common path 10, 5, 2, 1
PTT - long arm, factors 12, 11, 9, 8, and common path 10, 5, 2, 1

Bleeding time evaluates platelet function

Hemophilias have elevated PTT, but normal platelet function

Question 15

Heparin induced thrombocytopenia: presentation, pathophys, diagnosis, treatment

Answer 15

Presentation: skin necrosis at site of enoxaparin or heparin injection followed by formation of venous or arterial thrombus

Induced antibodies against platelet factor 4 -> platelet activation and clotting
Thrombocytopenia is d/t consumption of plts
High risk of venous and arterial thrombosis

Dx
Test for anti-Plt factor 4 Ab

Tx:
Prior to test results - discontinue drug
Start alternative a/c: fondaparinux, argatroban, bivalirudin
Transition to warfarin when normal platelet counts
-continue warfarin for 3-6 months with thrombus formation, 2-3 months without thrombus