S2268 A Unique Extra-Intestinal Manifestation of Ulcerative Colitis: Pulmonary Necrobiotic Nodules

Abstract

INTRODUCTION: Ulcerative colitis (UC) can have a variety of extra-intestinal manifestations, some of which include pulmonary complications. They can range from interstitial lung disease, organizing pneumonia, to necrobiotic nodules. Necrobiotic nodules are sterile aggregates of inflammatory cells with necrosis. The appearance of these nodules can mimic other cavitating diseases, making them a diagnostic challenge. CASE DESCRIPTION/METHODS: A 25-year-old man with a PMH of UC (on mesalamine and non-compliant with steroid suppositories) presented from an outside hospital (OSH) with fevers, abdominal pain, and bloody diarrhea for 1 week. Imaging from OSH revealed diffuse colitis as well as several pulmonary nodules. Repeat imaging at our institution, showed multiple necrotic, cavitary pulmonary nodules, initially concerning for septic emboli and the patient was started on empiric antibiotics. The patient denied any history of drug abuse, cardiac history, or dental procedures. On physical exam, there was tenderness to palpation in bilateral lower quadrants of the abdomen with no rebound tenderness, and no murmurs. Laboratory markers were significant for elevated ESR, CRP, and fecal calprotectin. Infectious etiologies were negative for bacterial, viral and fungal pathogens, and stool studies were negative as well. Cardiac MRI and TTE did not show any vegetation, and blood cultures showed no growth. Further pertinent testing was negative for vasculitis and autoimmune etiologies such as granulomatosis with polyangiitis, and rheumatoid arthritis. A CT guided lung biopsy revealed fibrosis with mixed inflammatory infiltrate containing macrophages, lymphocytes, scatter neutrophils and plasma cells. After poor follow up and not initiating any immunosuppressants, symptoms returned one month later, and imaging showed persistent pulmonary nodules. The patient was then started on steroids and subsequently bridged to biologic agents and symptoms improved. DISCUSSION: This case illustrates a rare manifestation of necrobiotic pulmonary nodules in a patient with poorly controlled UC. Before making this diagnosis, a thorough, yet pertinent differential such as malignancy, septic emboli, vasculitis, and infectious etiologies must be excluded. There are only two case reports of this UC complication. One patient was treated with a course of prednisone and imaging showed resolution of the nodules.Figure 1.: CT Chest With IV Contrast Showing Multiple Lung Nodules, Several Necrotic and Demonstrating Cavitation.