Abstract Introduction Gastrointestinal involvement of Anti-Neutrophil Cytoplasmic Antibody (ANCA) associated Vasculitis (AAV) is exceedingly rare. We present a case of hepatobiliary vasculitis unmasking systemic and pulmonary disease. Case report A sixty-six-year-old male with history of diabetic neuropathy presented with epigastric pain, subjective fevers, fatigue of few days duration. He had elevated liver enzymes and diagnosed with Cholecystitis. He underwent Cholecystectomy after initial supportive management with antibiotics. Surgical pathology demonstrated necrotizing vasculitis in small and medium sized vessels of gallbladder and surrounding adipose tissue. This prompted further investigation which revealed elevated p-ANCA (1:160) with Myeloperoxidase (MPO) specificity 167.8, PR-3 2 IU/L, high ANA titer 1640, erythrocyte sedimentation rate 75 mm/Hr; normal serum creatinine. On further questioning, he had dyspnea and pleuritic chest pain three weeks ago, a Computed Tomography of Chest (Fig A/B) showed left upper lobe cavitary lesion, diffuse bilateral ground glass opacities, minimal honeycombing, and traction bronchiectasis concerning for fibrotic Non-Specific Interstitial Pneumonia (NSIP); bronchoscopy with transbronchial biopsy at outside facility was negative for infection and granulomatous process. Remainder of autoimmune serologies, cryoglobulins, QuantiFERON-TB were negative; Immunoglobulin levels were normal. Persistently elevated liver enzymes following Cholecystectomy prompted Magnetic Resonance Cholangiopancreatography demonstrating hepatomegaly, heterogenous enhancement; core biopsies of liver was consistent with vasculitis. Overall clinical pattern was consistent with Microscopic Polyangiitis (MPA) and associated Interstitial Lung Disease (ILD). Once infectious etiologies were ruled out with a repeat Bronchoscopic lavage, he was successfully treated with high dose methylprednisone, induction therapy with Rituximab, and Trimethoprim-sulfamethoxazole for Pneumocystis prophylaxis. He is currently on maintenance therapy with Rituximab. Discussion AAV is a diagnostic challenge owing to its nonspecific, often overlapping symptoms with other granulomatous disease processes and requires high index of suspicion. Skin, lungs, and kidneys are mostly affected. Radiographically, MPA primarily presents as consolidative opacities, alveolar hemorrhage, ILD - predominantly Usual Interstitial Pneumonia pattern, unlike our patient with cavitary lung disease and early fibrotic NSIP. Absence of necrotizing granulomas, presence of vasculitis in gallbladder, liver along with serological evidence of p-ANCA with MPO specificity, supports the diagnosis of MPA in our patient. Treatment consists of induction with a combination of corticosteroids and Rituximab or Cyclophosphamide, followed by maintenance therapy with one of the following: Rituximab, Methotrexate, Mycophenolate, Azathioprine for a total of 12-24 months, upon inducing remission. This case underscores how visceral vasculitis, even when localized, may herald systemic MPO-ANCA associated disease with multi-organ involvement. This abstract is funded by: None
Thimmareddygari et al. (Fri,) studied this question.