CHRONIC HEMOLYTIC ANEMIA WITH PAROXYSMAL NOCTURNAL HEMOGLOBINEMIA

Abstract

A clinical syndrome characterized by chronic hemolytic anemia associated with paroxysmal nocturnal hemoglobinuria was independently described by Marchiafava¹ in 1928 and Micheli² in 1931. Since then several investigators³ have reported on the clinical manifestations of the disease, but its mechanism remained unknown until 1937, when T. H. Ham⁴ demonstrated the nature of the factors responsible for the production of the hemolysis. In a recent article in this journal T. H. Ham⁵ made the first comprehensive report on these factors. He demonstrated that the fundamental abnormality in this disease resides in the red blood cells, and not in the serum. He showed that the red blood cells of patients with the disease were abnormally sensitive to slight changes in pH. Lowering the pH, even within the physiologic range, always caused increased hemolysis, and raising the pH reduced or eliminated the hemolysis. Ham also demonstrated the presence of