Similar hematologic changes in children receiving trimethoprim-sulfamethoxazole or amoxicillin for otitis media

We report the hematologic changes in 90 black children who were randomized to receive a 10-day course of either trimethoprim-sulfamethoxazole (TMP-SMZ) or amoxicillin as therapy for acute otitis media. Absolute neutrophil counts <1500/mm³ developed at least once during the 23-day evaluation in 28 (57%) of the 49 children given TMP-SMZ and in 22 (54%) of the 41 who received amoxicillin. Incidence of leukopenia, thrombocytopenia, and anemia was negligible in both groups. Pancytopenia did not occur in any child. Absolute neutrophil counts had increased to >1500/mm³ by the end of the study period in all of the patients but six, whose recovery required an additional 1 to 63 days. Decreased neutrophil counts in antibiotic-treated subjects remained within the range of findings for healthy black children, suggesting that a count <1500/mm³ may be an inappropriate criterion for an adverse drug effect. Neither TMP-SMZ nor amoxicillin produced hematologic effects that would detract from their continued use in children with infections caused by antibiotic-susceptible organisms.