Role of exchange transfusion in patients with severe Falciparum malaria: report of six cases.

Abstract

Plasmodium falciparum malaria is associated with substantial mortality that parallels the degree of parasitemia or the development of complications. In addition to medical management, exchange transfusion (ET) has been occasionally used in the treatment of the most severe cases. We review the cases of six patients with severe falciparum malaria successfully treated with ET. Plasmodium falciparum malaria is the most dangerous form of malaria with a mortality exceeding 20% depending on the degree of parasitemia and the development of complications such as cerebral malaria, renal failure, adult respiratory distress syndrome (ARDS), and disseminated intravascular coagulation (DIC).1,2 Survival depends upon the prompt institution of medical therapy. Besides this, exchange-transfusion (ET) allows a brisk reduction in the level of parasitemia and can be considered as an useful adjunctive measure in the management of the most severe cases of falciparum malaria. 2,4,5 We present six patients with poor prognosis severe falciparum malaria successfully treated with ET in the Hematology Service of the University Hospital La Fe. At diagnosis, all patients were febrile and had acute renal failure (2 requiring hemodialysis), four had hepatic impairment, two had cerebral malaria, and one pulmonary edema requiring mechanical ventilation. The main characteristics of the patients are shown in Table 1. Drug therapy was started immediately after diagnosis, and ET was decided within 36 hours of the diagnosis due to the unfavorable evolution of the patients’ disease. ET was performed using either a discontinuous (3 cases) or continuous-flow blood cell separator (3 cases). The median blood volume removed was 7,000 mL and was substituted by an equivalent amount of a mixture of packed red blood cells (RBC) and fresh frozen plasma (FFP). A decrease in the infected erythrocyte rate was observed in every case. Three patients developed ARDS after the ET, requiring mechanical ventilation, and in two patients the renal failure progressed, requiring hemodialysis. However, all patients survived without sequelae. Plasmodium falciparum infects erythrocytes of any age with the potential for development of high-grade parasitemia.6 Clinical complications observed in falciparum malaria are the result of microthrombi caused by the presence of mature parasites in the microcirculation of various organs such as brain, kidneys, spleen, liver, intestines and limbs. 7,8 Despite appropriate medical treatment, the mortality in patients with a greater than 10% parasitemia ranges from 20% to 40% when cerebral or renal function is impaired and up to 80% in the presence of ARDS.2 In these cases, the use of ET is a valid approach to achieve a prompt reduction in parasitemia, and may improve prognosis. However, ET treatment is still considered a matter of debate because some authors consider that similar results to that achieved with ET could be obtained with chemotherapy alone. 9 In the only randomized, prospective study reported comparing antimalarial chemotherapy with or without ET, all four patients who received ET survived, whereas three out of four patients who did not receive ET died, supporting the benefit of ET in preventing malaria mortality. 10