Familial polycythemia

This code represents a rare, inherited disorder characterized by an abnormally high red blood cell count (erythrocytosis) that is not acquired or secondary to other conditions. It results from a genetic mutation leading to increased erythropoietin sensitivity or production, causing an overproduction of red blood cells.

Use this code for patients diagnosed with primary polycythemia that has a confirmed or strongly suspected familial or hereditary basis. Documentation should clearly indicate a genetic predisposition, family history of polycythemia, and exclusion of secondary causes such as chronic hypoxia or myeloproliferative neoplasms.

• Differentiate from Polycythemia Vera (238.4), which is a myeloproliferative neoplasm, not a familial condition.
• Ensure documentation specifies "familial" or "hereditary" to support this specific code.
• Do not use for secondary polycythemia due to conditions like COPD or high altitude.