Hematology High-Yield: Anemia and Bleeding Disorders for FNP Boards

Clinical High-Yield · 8 min read · May 15, 2026

The Anemia Framework

Every anemia question on the boards can be approached with one framework: MCV first.

• Low MCV (microcytic): Iron deficiency, thalassemia, sideroblastic anemia, anemia of chronic disease (can be normocytic)
• Normal MCV (normocytic): Anemia of chronic disease, hemolytic anemia, aplastic anemia, acute blood loss, renal disease
• High MCV (macrocytic): B12 deficiency, folate deficiency, hypothyroidism, liver disease, medications (methotrexate, hydroxyurea)

Iron Deficiency Anemia

Most common anemia worldwide. Most common cause in premenopausal women: menstrual blood loss. Most common cause in men and postmenopausal women: GI blood loss (must rule out malignancy).

Labs: Low MCV, low serum iron, low ferritin (most specific), high TIBC, low transferrin saturation.

Treatment: Oral ferrous sulfate 325 mg TID between meals. Vitamin C enhances absorption. Recheck CBC in 4–6 weeks. Treat underlying cause.

B12 Deficiency

Causes: Pernicious anemia (autoimmune, anti-intrinsic factor antibodies), strict veganism, gastric bypass, metformin (long-term use), Crohn's disease.

Labs: High MCV, hypersegmented neutrophils, low B12, elevated methylmalonic acid and homocysteine.

Neurological symptoms: Subacute combined degeneration — posterior and lateral column involvement → paresthesias, ataxia, weakness. Can be irreversible if untreated.

Treatment: IM cyanocobalamin if malabsorption. Oral high-dose B12 if dietary deficiency.

Folate Deficiency

Causes: Poor diet, alcohol use, pregnancy, medications (methotrexate, phenytoin, trimethoprim).

Labs: High MCV, hypersegmented neutrophils, low folate, elevated homocysteine (but normal methylmalonic acid — distinguishes from B12).

No neurological symptoms — key distinction from B12 deficiency.

Treatment: Oral folic acid 1 mg daily. Supplementation in pregnancy prevents neural tube defects.

Sickle Cell Disease

Autosomal recessive. HbS substitution. Sickling triggered by hypoxia, dehydration, cold, infection, stress.

Complications: Vaso-occlusive crisis (pain crisis), acute chest syndrome (fever + chest pain + infiltrate — emergency), stroke, splenic sequestration, avascular necrosis, priapism, renal disease.

Treatment: Hydroxyurea (increases HbF, reduces crises), folic acid supplementation, penicillin prophylaxis in children, pneumococcal vaccine, pain management.

Bleeding Disorders

Von Willebrand disease: Most common inherited bleeding disorder. Mucocutaneous bleeding (epistaxis, menorrhagia, easy bruising). Normal PT, prolonged PTT, low VWF antigen. Treatment: DDAVP for mild disease, VWF concentrate for severe.

Hemophilia A: Factor VIII deficiency. X-linked recessive. Deep tissue bleeding, hemarthroses. Prolonged PTT, normal PT. Treatment: Factor VIII replacement.

ITP (Immune Thrombocytopenic Purpura): Autoimmune platelet destruction. Petechiae, purpura, mucosal bleeding. Low platelets, normal PT/P...