Diagnosis of Aplastic Anemia
Patients with aplastic anemia generally present with symptoms of bleeding or bruising due to the thrombocytopenia (low platelets), tiredness or pallor due to the anemia (low hemoglobin), or infection due to the neutropenia (low white blood cell count). A complete blood count and reticulocyte count usually show depression of all blood elements (pancytopenia). The peripheral blood smear shows no abnormal cells. The diagnosis is confirmed by a bone marrow biopsy with an assessment of cellularity. The bone marrow is also evaluated for the degree of maturation of all cell lines. Aplastic anemia is usually categorized as severe if, in addition to a hypocellular bone marrow for age, two of the three following criteria are present: a platelet count of less than 20,000/mm3, a corrected reticulocyte count of less than 1%, and a granulocyte or absolute neutrophil count [ANC = total white count x (segs + bands)] of less than 500/mm3. Patients With pancytopenia, but not severe enough to meet the above criteria, have mild or moderate aplastic anemia. Very severe aplastic anemia exists if the ANC or granulocyte count is less than 200/mm3.
When aplastic anemia is diagnosed, all drugs or medications the patient is on should be stopped if possible. Tests to exclude specific causes of aplastic anemia should be done including a sugar water or a Ham test to rule out paroxysmal nocturnal hemoglobinuria (PNH), B12 and folate levels and Hepatitis A, B, and C serologies. Bone marrow chromosomes should be done to rule out a cytogenetic abnormality that may suggest a diagnosis of myelodysplastic syndrome. Peripheral chromosome analysis using diepoxybutane or mitomycin C should be done to rule out Fanconi's anemia in patients under 40 years of age. Patients who are under 55 years of age and their siblings and parents, if available, should be HLA typed at diagnosis to see if a bone marrow transplant is a therapeutic option.
Diagnosis of Aplastic Anemia
