Reactive Arthritis Due to Leptospirosis in a 11-Year-Old Adolescent Boy

Reactive arthritis is defined as a sterile inflammation of the joint space, following a remote infection, which can be bacterial or viral in origin. Although leptospirosis is not a frequent cause, it has been reported as a potential trigger. We herein report an 11-year-old boy who presented with fever, jaundice, and acute onset of right hip pain with restricted movement. Laboratory investigations were done to evaluate for infectious causes. IgM antibodies for <i>Leptospira</i> were equivocal, suggesting the possibility of an acute infection. This case highlights that reactive arthritis can develop early in the course of leptospiral infection, as early as within 3 days of symptom onset, and may coincide with active systemic illness. Early recognition of this rare association is essential for the diagnosis and management.