Immunosuppression increases the susceptibility to infection and changes the inflammatory response in children with severe protein-energy malnutrition. In this 5-year prospective study bacteremia was documented in 16% of 336 severely malnourished children, 2 to 34 months of age, who were hospitalized consecutively in the Tropical Metabolism Research Unit, Kingston, Jamaica. The 53 children had 60 episodes of nosocomial and community-acquired bacteremia with 69 blood isolates. Community-acquired bacteremia accounted for 72% (43 of 60) of bacteremic episodes. Thirty-five percent (24 of 69) of the strains were coagulase-negative staphylococci, 19% (13 of 69) were Staphylococcus aureus and 11% (8 of 69) were Streptococcus Group D. Seventeen episodes of coagulase-negative staphylococcal bacteremia were acquired in the community and 7 were nosocomial. These patients were more likely to have pneumonic consolidation than children with all other bacteremias combined (P < 0.02, Fisher's exact test). The bacteremia-related case fatality rate was 8% (5 of 60). Polymicrobial and Gram-negative septicemia were independent positive predictive factors for mortality when compared with single-agent and Gram-positive sepsis (P < 0.02). This 71% (49 of 69) prevalence of Gram-positive organisms suggests a change in the epidemiology from the predominant Gram-negative etiologies (76%) described in previous reports.