LATEST HEMATOLOGY CERTIFICATION EXAM
FOR THE AMERICAN BOARD OF INTERNAL
MEDICINE (ABIM) | COMPLETE EXAM Q&A
WITH RATIONALES
1. A 72-year-old male presents with fatigue and
unintentional weight loss. CBC shows Hb 8.5 g/dL,
MCV 105 fL, WBC 4.0, platelets 150,000. Peripheral
smear shows macro-ovalocytes and hypersegmented
neutrophils. What is the most appropriate next step?
A) Vitamin B12 and folate levels
B) Reticulocyte count
C) Bone marrow biopsy
D) Ferritin and iron studies
Correct answer: A
Rationale: Macrocytic anemia with hypersegmented
neutrophils suggests B12 or folate deficiency. Check
B12 and folate before empiric therapy.
2. A 68-year-old male with chronic lymphocytic
leukemia (CLL) presents with fever, fatigue, and
petechiae. CBC shows Hb 9.0, WBC 50,000, platelets
15,000. What is the most likely cause of
thrombocytopenia?
,A) Autoimmune destruction (ITP)
B) Bone marrow infiltration
C) Splenic sequestration
D) Drug-induced
Correct answer: B
Rationale: CLL commonly causes thrombocytopenia
from marrow infiltration. Autoimmune cytopenias
(ITP, AIHA) also occur but marrow infiltration is more
common with advanced disease.
3. A 55-year-old female presents with easy bruising
and menorrhagia. CBC is normal. PT and PTT are
prolonged. Mixing study corrects both PT and PTT.
What is the most likely diagnosis?
A) Factor deficiency (e.g., vitamin K deficiency)
B) Lupus anticoagulant
C) Factor VIII inhibitor
D) von Willebrand disease
Correct answer: A
Rationale: Correction of both PT and PTT on mixing
study suggests factor deficiency. Lupus
anticoagulant prolongs PTT only and does not
correct. vWD prolongs PTT only.
,4. A 45-year-old male with a history of unprovoked
deep vein thrombosis (DVT) is found to have a
positive lupus anticoagulant. What is the most
appropriate next step?
A) Start warfarin indefinitely
B) Repeat lupus anticoagulant in 12 weeks
C) Start apixaban
D) Test for factor V Leiden
Correct answer: B
Rationale: Antiphospholipid syndrome requires
persistent positivity (≥12 weeks). Repeat testing
before diagnosing APS. Anticoagulation is indicated
but diagnosis first.
5. A 70-year-old male with atrial fibrillation on
warfarin has an INR of 8.5. He has no bleeding. What
is the most appropriate next step?
A) Hold warfarin and give vitamin K 2.5 mg orally
B) Hold warfarin and give fresh frozen plasma
C) Hold warfarin only, recheck INR in 24 hours
D) Give prothrombin complex concentrate (PCC)
Correct answer: C
, Rationale: Asymptomatic INR 8.5 (>10 may use low-
dose vitamin K). Hold warfarin, recheck. Vitamin K
for INR >10 or bleeding risk.
6. A 32-year-old female presents with fatigue, pallor,
and shortness of breath. Hb 6.5 g/dL, MCV 110 fL,
WBC 2.5, platelets 80,000. Reticulocyte count is
0.5%. What is the most appropriate next step?
A) Bone marrow aspiration and biopsy
B) Vitamin B12 and folate levels
C) Direct antiglobulin test (Coombs test)
D) Serum iron studies
Correct answer: A
Rationale: Pancytopenia with low reticulocytes and
macrocytosis suggests bone marrow failure (aplastic
anemia, MDS). Bone marrow biopsy is diagnostic.
7. A 28-year-old male with sickle cell disease
presents with acute chest pain, fever, and
hypoxemia. Chest X-ray shows a new infiltrate in the
right lower lobe. What is the most appropriate next
step?
A) IV ceftriaxone and azithromycin
B) Exchange transfusion
FOR THE AMERICAN BOARD OF INTERNAL
MEDICINE (ABIM) | COMPLETE EXAM Q&A
WITH RATIONALES
1. A 72-year-old male presents with fatigue and
unintentional weight loss. CBC shows Hb 8.5 g/dL,
MCV 105 fL, WBC 4.0, platelets 150,000. Peripheral
smear shows macro-ovalocytes and hypersegmented
neutrophils. What is the most appropriate next step?
A) Vitamin B12 and folate levels
B) Reticulocyte count
C) Bone marrow biopsy
D) Ferritin and iron studies
Correct answer: A
Rationale: Macrocytic anemia with hypersegmented
neutrophils suggests B12 or folate deficiency. Check
B12 and folate before empiric therapy.
2. A 68-year-old male with chronic lymphocytic
leukemia (CLL) presents with fever, fatigue, and
petechiae. CBC shows Hb 9.0, WBC 50,000, platelets
15,000. What is the most likely cause of
thrombocytopenia?
,A) Autoimmune destruction (ITP)
B) Bone marrow infiltration
C) Splenic sequestration
D) Drug-induced
Correct answer: B
Rationale: CLL commonly causes thrombocytopenia
from marrow infiltration. Autoimmune cytopenias
(ITP, AIHA) also occur but marrow infiltration is more
common with advanced disease.
3. A 55-year-old female presents with easy bruising
and menorrhagia. CBC is normal. PT and PTT are
prolonged. Mixing study corrects both PT and PTT.
What is the most likely diagnosis?
A) Factor deficiency (e.g., vitamin K deficiency)
B) Lupus anticoagulant
C) Factor VIII inhibitor
D) von Willebrand disease
Correct answer: A
Rationale: Correction of both PT and PTT on mixing
study suggests factor deficiency. Lupus
anticoagulant prolongs PTT only and does not
correct. vWD prolongs PTT only.
,4. A 45-year-old male with a history of unprovoked
deep vein thrombosis (DVT) is found to have a
positive lupus anticoagulant. What is the most
appropriate next step?
A) Start warfarin indefinitely
B) Repeat lupus anticoagulant in 12 weeks
C) Start apixaban
D) Test for factor V Leiden
Correct answer: B
Rationale: Antiphospholipid syndrome requires
persistent positivity (≥12 weeks). Repeat testing
before diagnosing APS. Anticoagulation is indicated
but diagnosis first.
5. A 70-year-old male with atrial fibrillation on
warfarin has an INR of 8.5. He has no bleeding. What
is the most appropriate next step?
A) Hold warfarin and give vitamin K 2.5 mg orally
B) Hold warfarin and give fresh frozen plasma
C) Hold warfarin only, recheck INR in 24 hours
D) Give prothrombin complex concentrate (PCC)
Correct answer: C
, Rationale: Asymptomatic INR 8.5 (>10 may use low-
dose vitamin K). Hold warfarin, recheck. Vitamin K
for INR >10 or bleeding risk.
6. A 32-year-old female presents with fatigue, pallor,
and shortness of breath. Hb 6.5 g/dL, MCV 110 fL,
WBC 2.5, platelets 80,000. Reticulocyte count is
0.5%. What is the most appropriate next step?
A) Bone marrow aspiration and biopsy
B) Vitamin B12 and folate levels
C) Direct antiglobulin test (Coombs test)
D) Serum iron studies
Correct answer: A
Rationale: Pancytopenia with low reticulocytes and
macrocytosis suggests bone marrow failure (aplastic
anemia, MDS). Bone marrow biopsy is diagnostic.
7. A 28-year-old male with sickle cell disease
presents with acute chest pain, fever, and
hypoxemia. Chest X-ray shows a new infiltrate in the
right lower lobe. What is the most appropriate next
step?
A) IV ceftriaxone and azithromycin
B) Exchange transfusion
