Isolated small bowel disease and multiple lung nodules: an unusual initial presentation of pediatric Crohn’s disease

Crohn’s disease (CD) is a chronic idiopathic inflammatory disorder of the gastrointestinal tract characterized by transmural inflammation, skip lesions, and architectural changes. Isolated small bowel involvement is seen in approximately 1% of patients with CD at diagnosis. Extraintestinal manifestations can occur, with pulmonary involvement seen in <1% of all CD. We report an unusual case of a previously healthy 12-year old male who presented to hospital with acute abdominal pain, emesis, and fever. He had microcytic anemia, thrombocytosis, elevated C-reactive protein, hypoalbuminemia, digital clubbing, and poor growth. Interestingly, initial upper endoscopy and ileocolonoscopy were unremarkable. Pathology revealed colonic nonnecrotizing granulomas without inflammation. He incidentally was found to have multiple lung nodules despite the absence of respiratory symptoms, and MRE revealed five small bowel strictures. This prompted work-up for alternative etiologies including infectious and rheumatologic, which were negative. Ultimately, five months later, double balloon enteroscopy revealed ileal ulcerations at the strictures and several small aphthous ulcers in the transverse and sigmoid colon. Biopsies showed active ileitis and chronic active colitis with nonnecrotizing granulomas. He developed perianal disease, confirmed on MR pelvis, and a diagnosis of CD was made. The patient started infliximab therapy and is clinically in remission. This is a rare and unique phenotype of CD with initial presentation of multiple lung nodules and isolated small bowel disease. This case highlights the importance of recognizing that pulmonary manifestations should be considered in the absence of respiratory symptoms and that a normal first endoscopy does not preclude a diagnosis of CD.