Pathophysiology of acute falciparum malaria: I. Correlation of clinical and biochemical abnormalities

Abstract

This prospective study of naturally acquired falciparum malaria in twenty-six American soldiers was performed in Vietnam. All subjects were nonimmune, receiving weekly chemoprophylaxis, and studied during their initial clinical episode of malaria. The sequential changes in clinical and laboratory abnormalities are defined and correlated. Clinical observations which warrant increased emphasis include the high incidence and long duration of orthostatic hypotension and splenomegaly. In addition to previously reported laboratory abnormalities, severely ill patients had hyponatremia, reversal of the urinary sodium to potassium ratio, increased urinary aldosterone excretion and urinary osmolality markedly exceeding that of serum during hyponatremia. There was a positive correlation between the clinical illness and laboratory abnormalities. A hypothesis in which a decrease in effective circulating blood volume plays a central role is presented.