Prognostic significance of skin and subcutaneous fat sequestration of parasites in severe falciparum malaria.

Intradermal blood smear, histopathologic and immunohistologic studies were performed in severe malaria (n=10) and uncomplicated malaria (n=10) patients during positive parasitemia and within 6 hours after negative parasitemia by finger prick smears. Intradermal blood smears showed asexual forms and intraleukocytic pigments when finger prick blood smears showed negative results; however intradermal blood smear did not indicate disease severity within 6 hours after negative parasitemia by finger prick. Histopathologic findings showed 15 fold higher parasitized red blood cells sequestered in vessels of subcutaneous fatty tissue in severe malaria than in uncomplicated malaria (p<0.001) and may indicate disease severity. A panel of polyclonal antibodies against cytokines applied to skin biopsies clearly detected a higher titer against tumor necrosis factor-alpha (TNFalpha) and interleukin-10 (IL-10) in dermal vessels and stratum granulosum respectively, in severe malaria compared with uncomplicated malaria. Results of the study suggest that histopathology and immunohistology of skin and subcutaneous fatty tissue may indicate prognostic severity of malaria and may be associated with focal accumulation of cytokines.

Pulmonary edema in cerebral malaria patients in Thailand.

Pulmonary edema is a serious complication of falciparum malaria that usually occurs in association with cerebral malaria, acute renal failure, high parasitemias, or delayed antimalarial treatment. From 1993 to 1996, 120 adult patients admitted to the intensive care unit of the Bangkok Hospital for Tropical Diseases were enrolled in a prospective study to assess the combination of artesunate and mefloquine for the treatment of cerebral malaria. Twenty-five patients (21%) presented with pulmonary edema and a majority developed complications in other organs as well, especially acute renal failure. In most patients (19 of 25), pulmonary edema was noted on the first day of admission and was associated with higher parasitemias and levels of acidemia, than in patients without pulmonary edema. Ten of the 25 patients diagnosed with pulmonary edema developed signs consistent with adult respiratory distress syndrome (ARDS). The mean central venous pressure when pulmonary edema was diagnosed was markedly lower in ARDS than in non-ARDS patients, supporting the argument that fluid imbalance is not essential for malaria-induced lung injury. Seven of 10 patients with ARDS died, 5 within 24 hours of admission, but there were no deaths in the 15 pulmonary edema patients without ARDS. Early diagnosis and prompt treatment remain important principles to reduce the morbidity and mortality associated with complicated falciparum malaria. This report emphasizes that ARDS, when concurrently occurs, is a poor prognostic clinical indicator in cerebral malaria.