Increased usage of doxycycline for young children with Lyme disease

Background: The 2018 Infectious Disease Committee of the American Academy of Pediatrics stated that up to 3 weeks or less of doxycycline is safe in children of all ages. Our goal was to examine trends in doxycycline treatment for children with Lyme disease. Methods: We assembled a prospective cohort of children aged 1 to 21 years with Lyme disease who presented to one of eight participating Pedi Lyme Net centers between 2015 and 2023. We defined a Lyme disease case with an erythema migrans (EM) lesion or positive two-tier Lyme disease serology categorized by stage: early-localized (single EM lesion), early-disseminated (multiple EM lesions, cranial neuropathy, meningitis, and carditis), and late (arthritis). We compared doxycycline treatment by age and disease stage and used logistic regression to examine treatment trends. Results: Of the 1,154 children with Lyme disease, 94 (8.1%) had early-localized, 449 (38.9%) had early-disseminated, and 611 (53.0%) had late disease. Doxycycline treatment was more common for older children (83.3% ≥ 8 years vs. 47.1% < 8 years; p < 0.001) and with early-disseminated disease (77.2% early-disseminated vs. 52.1% early-localized or 62.1% late; p < 0.001). For children under 8 years, doxycycline use increased over the study period (6.9% 2015 to 67.9% 2023; odds ratio by year, 1.45; 95% confidence interval, 1.34–1.58). Conclusion: Young children with Lyme disease are frequently treated with doxycycline. Prospective studies are needed to confirm the safety and efficacy of doxycycline in children younger than 8 years, especially for those receiving courses longer than 3 weeks.