Inheritance: autosomal dominant or sporadic
Cytopenias:
(1) severe monocytopenia
(2) B-cell lymphocytopenia
(3) NK-cell lymphocytopenia
(4) absence of circulating dendritic cells
Distinctive features:
(1) onset of myelodysplasia (MDS) in early to middle adulthood
(2) infection with Mycobacterium avium-intracellulare (MAC)
(3) extensive warts or evidence of HPV infection
(4) large granular (T cells) lymphocytosis
In addition patients develop recurrent infections with fungi and other pathogens.
Bone marrow findings:
(1) Reticulin fibrosis is relatively common (2+ or higher).
(2) There is evidence of hypocellularity with trilineage dysplasia.
(3) Variable presence of plasma cells that are CD56+.
(4) Variable hemophagocytic histiocytosis.
(5) Variable cytogenetic abnormalities.
Patients may progress to acute myeloid leukemia (AML).