Bacteraemia in homozygous sickle cell disease in Africa: is pneumococcal prophylaxis justified?

Abstract

Background: The high frequency of Streptococcus pneumoniae as a cause of bacteraemia in homozygous sickle cell (SS) disease and its effective prevention has led to the routine use of pneumococcal prophylaxis in developed countries. The reported infrequency of this organism as a cause of bacteraemia in SS disease in Africa raises questions on the epidemiology of bacterial infection and on the need for pneumococcal prophylaxis in that continent.

Methods: A study of blood cultures in 155 Ugandan children (165 episodes) with SS disease and axillary temperatures of ≥38°C, attending the University Teaching Hospital in Kampala (Uganda, East Africa).

Results: Positive blood cultures, obtained in 47/165 episodes, showed Staphylococcus aureus in 28 (60%) samples, Haemophilus influenzae in 9 (19%), Staphylococcus epidermidis in 4 (9%), and single cases of Streptococcus viridans, Escherichia coli and an unidentified Gram negative rod. Streptococcus pneumoniae was identified in only 3 (6%) episode.

Conclusion: The infrequent isolation of Streptococcus pneumoniae from febrile children with SS disease in this study and in four other studies from Nigeria raises questions on a different spectrum of bacterial causes for bacteraemia in malarial areas. There are several possible explanations for this finding, but the data cast sufficient doubt on the case for pneumococcal prophylaxis for a controlled trial on its effectiveness in that environment to seem justified. These data are necessary to determine its role in African children and to provide the evidence base for healthcare authorities in equatorial Africa.