Malaria Burden in Pregnancy at Mulago National Referral Hospital in Kampala; Uganda

Pregnancy-associated malaria is a major global health concern. To assess the Plasmodium falciparum burden in pregnancy we conducted a cross-sectional study at Mulago Hospital in Kampala; Uganda. Malaria prevalence by each of three measures-peripheral smear; placental smear; and placental histology was 9(35/391); 11.3(44/389); and 13.9(53/382) respectively. Together; smear and histology data yielded an infection rate of 15.5(59/380) of active infections and 4.5(17/380) of past infections; hence 20had been or were infected when giving birth. A crude parity dependency was observed with main burden being concentrated in gravidae 1 through gravidae 3. Twenty-two percent were afflicted by anaemia and 12.2delivered low birthweight babies. Active placental infection and anaemia showed strong association (OR=2.8) whereas parity and placental infection had an interactive effect on mean birthweight (P=.036). Primigravidae with active infection and multigravidae with past infection delivered on average lighter babies. Use of bednet protected significantly against infection (OR=0.56) whilst increased haemoglobin level protected against low birthweight (OR=0.83) irrespective of infection status. Albeit a high attendance at antenatal clinics (96.8); there was a poor coverage of insecticide-treated nets (32) and intermittent preventive antimalarial treatment (41.5)

Molecular mechanisms and biological importance of Plasmodium falciparum erythrocyte rosetting

Rosetting, i.e. the spontaneous binding of uninfected to malaria infected erythrocytes and endothelial cytoadherence may hinder the blood flow and lead to serve Plasmodium falciparum malaria. Falciparum isolates obtained from unconscious patients all form rosettes and/or express a significantly higher man rosetting rate than isolates from patients with uncomplicated malaria. Furthermore, sera of patients with cerebral malaria are devoid of anti-rosetting activity while sera from patients with mild disease carry high levels of anti-rosetting antibodies. The presence of anti-rosetting antibodies also seems important for the efficient interaction of rosetting infected rbc and leucocytes. Two parasite derived rosetting ligands of Mr 22k and Mr28K named "rosettins, have been found on the surface of rosetting infected erythrocytes. CD36 has in at least some strains of parasites been found to function as a rosetting receptor on the uninfectederythrocyte. Heparin disrupts rosettes of P. falciparum in vitro and inhibits the sequestration of rosetting cells ex vivo. In conclusion, rosetting seems a crucial factor in the development of cerebral malaria and treatment of patients with anti-rosetting substances might become an effectivew adjunct in the treatment of severe malaria