Forty-three nonhemophiliac, confirmed HIV-positive children followed by the Children's Hospital AIDS Program made 184 visits to the children's Emergency Department (ED) during 1988 and 1989. The mean age was 30 +/- 28 months with a median of 25 months, a mode of 10 months, and a range from two days to 19 years. CD4 counts from within six months of the visit were available in 87% and were low enough to require Pneumocystis carinii pneumonia prophylaxis under current guidelines in 52%. Chief complaints included fever in 50%, respiratory symptoms in 21%, and gastrointestinal symptoms in 8%. The ED discharge diagnosis included fever/possible sepsis in 25%, pneumonia in 17%, otitis media in 9%, and upper respiratory tract infection or viral syndrome in 9%. Overall, an acute infection was identified at 62% of visits; of these, 33% were judged to be serious in nature. A total of 92 blood cultures were drawn, of which eight were positive with the following organisms: Streptococcus pneumoniae (3), Streptococcus faecalis (2), Escherichia coli (1), Torulopsis glabrata (1), and Staphylococcus non-aureus (1, a probable contaminant). Overall, 53% of patient encounters resulted in hospitalization. Patients with a white blood cell count more than 15,000/mm3 were more likely to be hospitalized (87 vs 62%, P < 0.01), though the white blood cell count was not helpful in identifying patients with bacteremia or serious infections. The mean temperature of patients admitted was higher than in those discharged (38.7 vs 37.9 degrees C, P < 0.01). In 1989, an estimated six per 1000 visits to our facility were by HIV-infected children.