It usually appears in middle age to elderly individuals, and only rarely in younger people. There is an equal incidence of agnogenic myeloid metaplasia in males and females. Patients with agnogenic myeloid metaplasia can appear relatively healthy for years. In later stages of the disease, however, patients present with fever, weight loss, and sweating.
Anemia associated with agnogenic myeloid metaplasia can also result in fatigue and weakness.
Physical examination will show splenomegaly, and gout due to hyperuricemia. The fibrosis in agnogenic myeloid metaplasia is a result in a defect in regulation, production and degradation of reticulin. Patients with agnogenic myeloid metaplasia will usually show increased reticulin, even in early stages of the disease. The megakaryocytic component is not unusual, and there are no distinctive chromosomal abnormalities. Median survival for patients with agnogenic myeloid metaplasia is 4-5 years.