Adverse Events in Pediatric Patients Receiving Long-Term Outpatient Antimicrobials

Background Although long treatment courses of outpatient antimicrobials are often used in pediatric patients, few data exist regarding the frequency of adverse events (AEs) associated with these medications. Methods We performed a retrospective cohort study of all patients seen in the Infectious Diseases clinic at a tertiary referral children's hospital from August 1, 2009 to August 1, 2011. We included patients who received ≥14 days of oral or intravenous antibiotic, antiviral, or antifungal medications. Patients receiving only prophylactic medications or human immunodeficiency virus treatment were excluded. Results Three hundred thirty-five subjects met inclusion criteria, with a median age of 7.4 years at start of therapy. The cohort was predominantly male (60%), white (54%), and previously healthy (59%). A majority (88.4%) of subjects were treated for bacterial infections. β-Lactam agents were the most commonly used antimicrobial class (210 subjects; 62.7%), followed by clindamycin (86; 25.7%), rifampin (76; 22.7%), and vancomycin (62; 18.5%). Overall, 107 (31.9%) subjects experienced 151 distinct AEs. The most common individual AE noted was diarrhea (44; 29.1% of all AEs). Serious AEs developed in 42 (12.5%) subjects, including allergic reactions (15; 11.3% of all AEs), venous catheter-related complications (14; 13.0% of those with catheters), neutropenia (9; 3.0%), renal insufficiency (7; 2.5%), and hepatotoxicity (3; 1.1%). Rates of AEs were similar between those on oral and intravenous antimicrobials. Conclusions In our study population, patients on prolonged oral or intravenous outpatient antimicrobials experienced AEs frequently. These findings support the need for close monitoring of pediatric patients on prolonged antimicrobial therapy and vigilance for unwanted effects of these medications.