Table 2.

Differential diagnosis of hypocellular marrow failure

Acquired	Inherited
aAA	Classical IBMFS/MMP Fanconi anemia Short telomere syndromes Shwachman-Diamond Syndrome GATA2 deficiency SAMD9/SAMD9L disorders
Anorexia nervosa
Hypocellular myelodysplastic syndrome	Inborn errors of immunity (eg, X-linked lymphoproliferative disorder)
Medications/toxins

This table is not exhaustive and is intended to capture the more commonly encounter entities that can present as aplastic anemia. In our clinical experience, the IBMFSs/MMPs listed here are not always characterized by hypocellular marrows. Gelatinous degradation of the bone marrow also may be seen in anorexia nervosa.²