F.2.Low absolute neutrophil counts in malawi infants
Kourtis A1, van der Horst C2, Kazembe P3, Ahmed Y1, Chasela C4, Hosseinipour M4, Lugalia L4, Tegha G4, Joaki G4, Jamieson D1
1Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA; 2 University of North Carolina, Chapel Hill, NC; 3 Kamuzu Central Hospital, Lilongwe, Malawi, UNC Project, Lilongwe, Malawi
Objectives: During initial stages of a mother and infant clinical trial in Malawi (BAN) we noted an unexpectedly high number of infants with absolute neutrophil counts (ANC) classifiable as neutropenia using the DAIDS toxicity table. A review was done to determine if the current DAIDS tables are relevant in African populations.
Methods: BAN is an open-label interventional trial and that includes both a 2-arm maternal nutrition intervention to promote maternal health and a 3-arm ART intervention with drugs given to the mother, the infant, or neither to prevent HIV transmission during breast feeding. Neutrophil counts were performed on a Beckman AcT5 analyzer; low counts were confirmed with manual differentials. For grading severity of infant adverse experiences we used the 1992 Division of AIDS (DAIDS) Toxicity Table.
Results: 85 infants enrolled in the study by January 31, 2004. Of these, 41 (48.2%) had neutropenia of any grade, while 5 (5.8%) had ANC of grade 3 or 4, at birth or within the first months of life. All cases of neutropenia were unrelated to study drug plus the infants were asymptomatic. Data to date reveals that the neutropenia quickly resolved without any change in drug regimen. No clinical events attributable to neutropenia were noted.
Conclusions: The data suggests that ANC cut points used to define neutropenia may not be suitable for African infants. The Neutrophil counts in our setting are generally lower than in western, white populations.
Recommendations: Until more data are available, we adjusted the ANC cut points that define neutropenia in infants<56 days of life by using the same cut points as for infants older that 56 days. DAIDS should consider modifying the toxicity table for neutropenia in young infants to take into account ethnic differences. There is need for a systematic pediatric haematology survey to determine normal ranges in Malawi.