PARANEOPLASTIC HYPOKALEMIA IN ACUTE MYELOID-LEUKEMIA - A CASE OF RENIN-ACTIVITY IN AML BLAST CELLS

Hypokalemia due to renal potassium loss has frequently been observed i n patients with acute myeloid leukemia (AML). The pathogenic mechanism for this hyperkaluresis is unclear. In this report we describe a pati ent with AML FAB M4, in whom the clinical course, the electrolyte dist urbances, the serum aldosterone levels, and the diffuse hyperplasia of the adrenal cortex documented a typical case of marked secondary hype raldosteronism. On analysis of the leukemic cells of this patient comp ared with normal bone marrow cells, a significant increase of renin-li ke activity in the cytosol of the blast cells was noted. Activation of the renin-angiotensin-aldosterone system by paraneoplastic production of renin-like activity in AML blast cells might contribute to the hyp okalemia often observed in patients with acute myeloid leukemia.