Lung lesions in children with Crohn's disease are often difficult to diagnose and treat. We report here 3 children (aged 13, 14, and 17 years) on immunosuppressive therapy for previously diagnosed Crohn's disease who presented with nonresolving pneumonias. All 3 had unfavorable response to empiric antibiotics and had progression of lesions. Cultures of sputum and blood did not yield any organisms. Subsequent lung biopsies revealed noncaseating granulomas with giant cells in 2 subjects and bronchiolitis obliterans with organizing pneumonia in the third. All patients were treated with infliximab, a novel anti-tumor necrosis factor monoclonal antibody, and showed rapid clinical and radiologic response. We emphasize that a high index of suspicion for noninfectious etiologies needs to be maintained in patients with Crohn's disease who present with lung lesions to ensure timely intervention. Infliximab therapy seems to be effective and well tolerated in such patients.