1/2. Severe malaria in a splenectomised Gabonese woman.BACKGROUND: The intact splenic function is of utmost importance for the host's defence capacity against Plasmodium spp. not only by limiting the acute infection through the removal of parasites from the blood stream, but also by modulating parasite antigen expression on the surface of infected red blood cells as well as cellular and humoral immune response. Splenectomised individuals are at high risk to develop a more severe and prolonged disease, even if they had acquired semi-immunity prior to their loss of splenic tissue. CASE REPORT: We report on a 37 year old splenectomised Gabonese woman who developed severe falciparum malaria with hyperparasitaemia, profound anaemia, and an overwhelming gametocytaemia, recovering very slowly following quinine therapy. Whereas the clinical course is not at odds with previous descriptions, the massive occurrence of mature gametocytes as documented here has not been reported before. Whether the high gametocyte count observed in our patient was primarily due to the impaired clearance of asexual forms or to the induction of gametocytogenesis remains unclear. Regarding the optimal drug regimen for treating malaria in splenectomized patients, a combination of an aminoquinoline with an artemisinin derivative might be the optimal choice.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/2. malaria in splenectomized patients: report of four cases and review.The spleen plays a central role in host defense against malaria in animals. Its role in human malaria is less well established. The spleen may contribute to protection against human malaria by mediating humoral or cellular immune responses or by clearing both rheologically and immunologically altered host erythrocytes. This report describes plasmodium falciparum and plasmodium vivax infections that occurred after splenectomy in one nonimmune and three partially immune Thai adults. The clinical course was uncomplicated for all four patients, and parasite clearance was delayed only in the nonimmune patient. In three patients with falciparum malaria, humoral and cellular immune responses to blood-stage antigens during the acute infection and convalescence were similar to those of individuals whose spleens were intact. These findings suggest that the spleen may not be essential for the processes leading to parasite clearance in partially immune, splenectomized patients. Further studies on the course of malarial infections in splenectomized patients are crucial for clarifying the role of the spleen in host defense against human malaria.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |