AAFP Board Review - HemOnc
A 43-year-old female complains of easy bruising. She is otherwise asymptomatic. A
CBC
reveals a platelet count of 23,000/mm3 (N 150,000-450,000). A peripheral smear
reveals giant
platelets. A workup is negative for autoimmune causes, including Graves disease, HIV,
Epstein-Barr virus, cytomegalovirus, varicella zoster, hepatitis C, and Helicobacter
pylori. She
is on no prescription or over-the-counter medications and denies alcohol or drug use.
Which one of the following would be the most appropriate initial management? (check
one)
A. Platelet transfusion
B. Corticosteroids
C. Thrombopoietin-receptor agonists
D. A bone marrow biopsy
E. Splenectomy - Answers -B. Corticosteroids - Immune (idiopathic) thrombocytopenic
purpura
- acquired immune-mediated disorder with
isolated thrombocytopenia not found to have another cause
- Treat severe thrombocytopenia (platelet count <50,000/mm3) unless there is evidence
of acute bleeding.
- Corticosteroids first-line therapy or Intravenous immunoglobulin and rituximab
- thrombopoietin-receptor agonists 2nd line or splenectomy.
- bone marrow biopsy, to rule out myelodysplastic
syndrome and lymphoproliferative disorders is indicated in patients over the age of 60
- no platelet transfusion
A 55-year-old white male comes to your office with weakness and a headache. He also
describes an annoying pruritus that occurs frequently after he takes a hot shower. The
physical examination is remarkable for the presence of an enlarged spleen. He has a
hemoglobin level of 21 g/dL (N 12-16) and a hematocrit of 63% (N 36-48). To confirm
your clinical diagnosis, you obtain additional studies.
Which one of the following would be most consistent with the most likely diagnosis in
this patient? (check one)
A. A low serum erythropoietin level
B. A low platelet count
C. A low arterial oxygen concentration
D. An elevated carboxyhemoglobin level - Answers -A. A low serum erythropoietin level
- polycythemia vera.
- Pruritus after a hot shower (aquagenic pruritus) and splenomegaly distinguish
polycythemia vera from other causes of erythrocytosis (hematocrit >55%).
, - Specific criteria: elevated red cell mass, a normal arterial oxygen saturation (>92%)
- a low serum erythropoietin level
- thrombocytosis (platelet count >400,000/mm3 ), leukocytosis (WBC>12,000/mm3 )
- high leukocyte alkaline phosphatase score
- High carboxyhemoglobin levels are associated with secondary polycythemia.
A 62-year-old African-American female undergoes a workup for pruritus. Laboratory
findings include a hematocrit of 55.0% (N 36.0-46.0) and a hemoglobin level of 18.5
g/dL (N 12.0-16.0).
Which one of the following additional findings would help establish the diagnosis of
polycythemia vera? (check one)
A. A platelet count >400,000/mm3
B. An O2 saturation <90%
C. A WBC count <4500/mm (N 4300-10,800)3
D. An elevated uric acid level - Answers -A. A platelet count >400,000/mm3
Major criteria
- increased red cell mass, a normal O2 saturation, splenomegaly
Minor criteria
-high vitamin B 12, elevated leukocyte alkaline phosphatase, a platelet count
>400,000/mm3 and a WBC count >12,000/mm3 .
- Patients with polycythemia vera may present with gout and an elevated uric acid level,
but neither is considered a criterion for the diagnosis.
Which one of the following causes of anemia is associated with a normal red cell
distribution width? (check one)
A. Vitamin B12 deficiency
B. Iron deficiency
C. β-Thalassemia trait
D. Sideroblastic anemia
E. Myelofibrosis - Answers -C. beta Thalassemia
- Red cell distribution width (RDW) is a measure of the variability of size of the red cells.
- particularly useful in distinguishing anemic disorders
- especially iron deficiency anemia (high RDW, normal to low mean corpuscular volume)
- uncomplicated heterozygous thalassemia (normal RDW, low mean corpuscular
volume).
In a patient with microcytic anemia, which one of the following patterns of laboratory
abnormalities would be most consistent with iron deficiency as the underlying cause?
(check one)
A. Ferritin low, total iron binding capacity (TIBC) low, serum iron low
B. Ferritin low, TIBC low, serum iron high
C. Ferritin low, TIBC high, serum iron low
D. Ferritin high, TIBC low, serum iron low - Answers -C. Ferritin low, TIBC high, serum
iron low
- Ferritin and serum iron levels fall with iron deficiency.
A 43-year-old female complains of easy bruising. She is otherwise asymptomatic. A
CBC
reveals a platelet count of 23,000/mm3 (N 150,000-450,000). A peripheral smear
reveals giant
platelets. A workup is negative for autoimmune causes, including Graves disease, HIV,
Epstein-Barr virus, cytomegalovirus, varicella zoster, hepatitis C, and Helicobacter
pylori. She
is on no prescription or over-the-counter medications and denies alcohol or drug use.
Which one of the following would be the most appropriate initial management? (check
one)
A. Platelet transfusion
B. Corticosteroids
C. Thrombopoietin-receptor agonists
D. A bone marrow biopsy
E. Splenectomy - Answers -B. Corticosteroids - Immune (idiopathic) thrombocytopenic
purpura
- acquired immune-mediated disorder with
isolated thrombocytopenia not found to have another cause
- Treat severe thrombocytopenia (platelet count <50,000/mm3) unless there is evidence
of acute bleeding.
- Corticosteroids first-line therapy or Intravenous immunoglobulin and rituximab
- thrombopoietin-receptor agonists 2nd line or splenectomy.
- bone marrow biopsy, to rule out myelodysplastic
syndrome and lymphoproliferative disorders is indicated in patients over the age of 60
- no platelet transfusion
A 55-year-old white male comes to your office with weakness and a headache. He also
describes an annoying pruritus that occurs frequently after he takes a hot shower. The
physical examination is remarkable for the presence of an enlarged spleen. He has a
hemoglobin level of 21 g/dL (N 12-16) and a hematocrit of 63% (N 36-48). To confirm
your clinical diagnosis, you obtain additional studies.
Which one of the following would be most consistent with the most likely diagnosis in
this patient? (check one)
A. A low serum erythropoietin level
B. A low platelet count
C. A low arterial oxygen concentration
D. An elevated carboxyhemoglobin level - Answers -A. A low serum erythropoietin level
- polycythemia vera.
- Pruritus after a hot shower (aquagenic pruritus) and splenomegaly distinguish
polycythemia vera from other causes of erythrocytosis (hematocrit >55%).
, - Specific criteria: elevated red cell mass, a normal arterial oxygen saturation (>92%)
- a low serum erythropoietin level
- thrombocytosis (platelet count >400,000/mm3 ), leukocytosis (WBC>12,000/mm3 )
- high leukocyte alkaline phosphatase score
- High carboxyhemoglobin levels are associated with secondary polycythemia.
A 62-year-old African-American female undergoes a workup for pruritus. Laboratory
findings include a hematocrit of 55.0% (N 36.0-46.0) and a hemoglobin level of 18.5
g/dL (N 12.0-16.0).
Which one of the following additional findings would help establish the diagnosis of
polycythemia vera? (check one)
A. A platelet count >400,000/mm3
B. An O2 saturation <90%
C. A WBC count <4500/mm (N 4300-10,800)3
D. An elevated uric acid level - Answers -A. A platelet count >400,000/mm3
Major criteria
- increased red cell mass, a normal O2 saturation, splenomegaly
Minor criteria
-high vitamin B 12, elevated leukocyte alkaline phosphatase, a platelet count
>400,000/mm3 and a WBC count >12,000/mm3 .
- Patients with polycythemia vera may present with gout and an elevated uric acid level,
but neither is considered a criterion for the diagnosis.
Which one of the following causes of anemia is associated with a normal red cell
distribution width? (check one)
A. Vitamin B12 deficiency
B. Iron deficiency
C. β-Thalassemia trait
D. Sideroblastic anemia
E. Myelofibrosis - Answers -C. beta Thalassemia
- Red cell distribution width (RDW) is a measure of the variability of size of the red cells.
- particularly useful in distinguishing anemic disorders
- especially iron deficiency anemia (high RDW, normal to low mean corpuscular volume)
- uncomplicated heterozygous thalassemia (normal RDW, low mean corpuscular
volume).
In a patient with microcytic anemia, which one of the following patterns of laboratory
abnormalities would be most consistent with iron deficiency as the underlying cause?
(check one)
A. Ferritin low, total iron binding capacity (TIBC) low, serum iron low
B. Ferritin low, TIBC low, serum iron high
C. Ferritin low, TIBC high, serum iron low
D. Ferritin high, TIBC low, serum iron low - Answers -C. Ferritin low, TIBC high, serum
iron low
- Ferritin and serum iron levels fall with iron deficiency.
