PROLONGED MACROPHAGE ACTIVATION AND PERSISTENT ANEMIA IN CHILDREN WITH COMPLICATED MALARIA

OBJECTIVE To determine if prolonged immune activation may be associate d with the persistence of anaemia after treatment for severe malaria, we measured serum concentrations of neopterin and interleukin-4 during one week of antimalarial therapy and determined haemoglobin levels on e month later. Neopterin is a clinically valuable marker for monitorin g activation of macrophages by gamma-interferon and thus reflects the TH-1 immune response. Interleukin-4 is a major cytokine that tends to be inhibited by TH-1 activity. METHOD The study population consisted o f 26 Zambian children <6 years of age who presented with cerebral mala ria to a rural hospital in 1994 and who were treated with quinine for seven days. Six children (23%) were anaemic (haemoglobin < 11 g/dl) on e month after completing antimalarial therapy RESULTS On admission, co ncentrations of neopterin were markedly elevated in all patients. Duri ng the seven days of anti-malarial therapy, neopterin levels remained elevated in the 6 children who proved to have persistent anaemia one m onth after finishing treatment but declined significantly (P = 0.008) in the 20 children who corrected their haemoglobin levels by that time . Conversely, interleukin-4 levels declined in the children with persi stent anaemia (P = 0.043) but not in the other children. CONCLUSION Pe rsistence of the TH-1 mediated immune response and associated activati on of macrophages may be involved in the pathogenesis of lingering ana emia after treatment of malaria.