1. A survey of 66 cases of the myeloproliferative syndromes revealed two clinical conditions not associated specifically with this group of blood dyscrasias.
2. Of particular interest were an apparent increased incidence of diabetes mellitus, and myelofibrosis associated with scleroderma.
3. These combinations may reflect a biochemical or metabolic error which may be present in some of these patients (such as increased 5-HIAA) and which may be related to the course, progression, and symptomatology of these disorders.