PANCE (Physician Assistant National Certifying Exam) — All Questions

A 35-year-old woman with heavy menstrual periods has fatigue. Hemoglobin is 9.8 g/dL with a low MCV. Which laboratory result is most consistent with iron deficiency?

• a.Elevated serum ferritin
• b.Low serum ferritin✓
• c.Low total iron-binding capacity
• d.Increased hemoglobin A2

A low serum ferritin is the most specific finding of iron deficiency, usually with low transferrin saturation and a high total iron-binding capacity. An elevated ferritin and low TIBC point toward anemia of inflammation. An increased hemoglobin A2 suggests beta-thalassemia trait, another cause of microcytosis.

A 70-year-old woman has macrocytic anemia, numbness in her feet, and impaired vibration sense. Her vitamin B12 level is low. Why should folic acid alone not be used to treat her?

• a.It precipitates a hemolytic crisis in B12 deficiency
• b.It may fix the anemia while nerve damage progresses✓
• c.It blocks the intestinal absorption of vitamin B12
• d.It worsens the macrocytosis over time

Folic acid can improve the megaloblastic anemia of B12 deficiency while the neurologic damage continues to progress, so vitamin B12 itself must be replaced. Folate does not trigger hemolysis, does not block B12 absorption, and does not worsen macrocytosis; the danger is that it masks the hematologic clue.

A 16-year-old with sickle cell anemia has had four vaso-occlusive pain crises requiring admission this year and one episode of acute chest syndrome. Which medication reduces the frequency of these events by increasing fetal hemoglobin?

• a.Folic acid
• b.Oral iron sulfate
• c.Hydroxyurea✓
• d.Deferoxamine

Hydroxyurea raises fetal hemoglobin (Hb F), which reduces sickling and decreases the frequency of pain crises and acute chest syndrome. Deferoxamine chelates iron in transfusional overload, folic acid supports red cell production, and oral iron is not indicated and may add to iron overload in chronically transfused patients.

A 26-year-old woman has new petechiae and gum bleeding. Platelet count is 12,000/µL; hemoglobin, white cell count and smear are otherwise normal, and there is no splenomegaly. HIV and hepatitis C tests are negative. Which diagnosis is most likely?

• a.Thrombotic thrombocytopenic purpura
• b.Acute myeloid leukemia
• c.Immune thrombocytopenia✓
• d.Disseminated intravascular coagulation

Isolated thrombocytopenia with an otherwise normal blood count and smear, no splenomegaly, and no secondary cause is immune thrombocytopenia, a diagnosis of exclusion. TTP shows schistocytes, hemolytic anemia and often neurologic or renal involvement. DIC prolongs clotting times and lowers fibrinogen, and acute leukemia causes abnormal white cells or blasts and other cytopenias.

A 3-year-old boy has a swollen, painful knee after a minor fall, and his maternal uncle had a bleeding disorder. Platelet count and prothrombin time are normal, and the partial thromboplastin time is prolonged. Which test most directly confirms the likely diagnosis?

• a.Factor VIII and IX activity assays✓
• b.Plasma fibrinogen level
• c.Bleeding time measurement
• d.Platelet aggregation studies

Hemarthrosis in a boy with an affected maternal relative, a prolonged PTT, and a normal PT and platelet count suggest hemophilia A or B, confirmed with specific factor VIII and IX assays. Bleeding time and platelet aggregation studies assess platelet function, which is normal in hemophilia. Fibrinogen deficiency would prolong both PT and PTT.

A 68-year-old man has back pain, fatigue, a hemoglobin of 9.5 g/dL, serum calcium of 11.8 mg/dL, and rising creatinine. Total serum protein is high with a normal albumin. Which test best supports the suspected diagnosis?

• a.Direct antiglobulin (Coombs) test
• b.Serum protein electrophoresis✓
• c.Hemoglobin electrophoresis
• d.Serum ferritin

Bone pain, anemia, hypercalcemia and renal insufficiency in an older adult suggest multiple myeloma, which is supported by detecting a monoclonal protein on serum (and urine) protein electrophoresis with immunofixation plus serum free light chains, followed by bone marrow examination. Hemoglobin electrophoresis evaluates hemoglobinopathies, ferritin evaluates iron stores, and the Coombs test detects immune hemolysis.