The bone marrow biopsy is the gold standard test for the diagnosis of aplastic anemia. A hematopathologist will review the bone marrow biopsy findings, and confirmatory results for aplastic anemia include hypoplasia with <20% cellularity, normal maturation of all cell lines, presence of fat cells and stroma in bone marrow space. Residual hematopoietic cells are morphologically normal. Hematopoiesis is not megaloblastic.

The bone marrow biopsy is the gold standard test for the diagnosis of aplastic anemia^[1]

The following findings on performing bone marrow biopsy are confirmatory for aplastic anemia:

• Hypoplasia with <20% cellularity
• Normal maturation of all cell lines
• Presence of adipose cells and stroma in bone marrow space
• Presence of morphologically normal residual hematopoietic cells
• Absence of megaloblastic hematopoiesis

• In adults with aplastic anemia, these tests should be done to detect coexistent disorders, such as paroxysmal nocturnal hemoglobinuria, myelodysplastic syndrome, or acute leukemia^[2]:
  • Flow cytometry for assessment of cell surface CD59 on peripheral blood red blood cells or neutrophils.
  • Cytogenetic and molecular testing of bone marrow
  • Hemoglobin electrophoresis and blood-group testing
  • Serology
  • Fluorescence-activated cell sorter (FACS) profiling
  • Fluorescent-labeled inactive toxin aerolysin (FLAER) testing
  • Diepoxybutane incubation
  • Histocompatibility testing

• In children with aplastic anemia, genetic testing should be performed to find out inherited genetic abnormalities.
  • Fanconi anemia
  • Dyskeratosis congenita
  • Short telomere syndromes