A RARE RADIOGRAPHIC MANIFESTATION OF A CHRONIC COUGH

Abstract

TOPIC: Imaging TYPE: Medical Student/Resident Case Reports INTRODUCTION: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is characterized by small vessel necrotizing vasculitis. AAV, including microscopic polyangiitis (MPA), is uncommonly association with interstitial lung disease (ILD). We present a pulmonary presentation of MPA with unique radiographic manifestations. CASE PRESENTATION: A 68-year-old woman with history of hypertension, hyperlipidemia, chronic lymphocytic thyroiditis and obesity presented with 8 weeks of dry hacking cough, associated with dyspnea on exertion and a 20lb weight loss. She was without sinusitis, visual changes, hemoptysis, abdominal symptoms, paresthesia, skin changes, or arthritis. Her initial prescriptions of loratadine and 10-days of doxycycline, then 10-days of prednisone had no effect. She was transitioned off Lisinopril to only mild improvement in her cough.The ILD CHEST questionnaire was completed without obvious toxic insult noted [1]. Her initial workup revealed mild leukocytosis (13), urinalysis with 1+ occult blood, normal Creatine Kinase, Aldolase, Thyroid studies, Liver function tests, electrolytes, and creatinine. Infectious workup was negative for HIV and COVID-19. High-resolution chest imaging demonstrated bilateral central bronchial wall thickening and inflammation and no pleural reticulation, honeycombing, nor adenopathy.Bronchoscopy with transbronchial and endobronchial biopsies revealed intra-alveolar hemorrhage and hemosiderin-laden macrophages but without definitive vasculitis. Infectious workup was unremarkable. Antinuclear and glomerular basement membrane antibody testing was negative. Serologic testing was notable for perinuclear anti-neutrophil cytoplasmic antibody titer of 1:640 (<1:20) and positive myeloperoxidase antibodies. Nephrology evaluation showed evidence of glomerulonephritis with dysmorphic hematuria and proteinuria, and Rheumatological evaluation revealed elevated sedimentation rate 120 mm/H (<20) and C-reactive protein 61mg/L (<10). DISCUSSION: Given concern for pulmonary and renal end-organ involvement, prednisone 60mg daily with Bactrim for Pneumocystis Jirovecii prophylaxis was started. Her cough markedly improved. Her case was discussed internally at our Multidisciplinary ILD board and she was transitioned to Rituximab induction for MPA/AAV treatment. Her cough has resolved with no functional dyspnea while on therapy. CONCLUSIONS: ILD is an uncommon associated finding in MPA. When present, more common radiographic manifestations include ground glace opacities, reticulations, interlobular septal thickening and even honeycombing (2). Our case was notable for radiographic central bronchial wall thickening and inflammation alone, a rare manifestation [2,3]. When present, bronchial wall thickening is typically seen in association with usual interstitial pneumonia or diffuse alveolar hemorrhage [2]. The latter of which was identified during our patient's bronchoscopy. REFERENCE #1: www.chestnet.org. [last accessed 2021 April 20]. REFERENCE #2: Suzuki A, Sakamoto S, Kurosaki A, Kurihara Y, Satoh K, Usui Y, Nanki T, Arimura Y, Makino H, Okada Y, Harigai M, Yamagata K, Sugiyama H, Dobashi H, Ishizu A, Tsuboi N, Usui J, Sada KE, Homma S; for Japan Research Committee of the Ministry of Health, Labour, and Welfare for Intractable Vasculitis and Research Committee of Intractable Renal Disease of the Ministry of Health, Labour, and Welfare of Japan. Chest High-Resolution CT Findings of Microscopic Polyangiitis: A Japanese First Nationwide Prospective Cohort Study. AJR Am J Roentgenol. 2019 Jul;213(1):104-114. doi: 10.2214/AJR.18.20967. Epub 2019 Apr 11. PMID: 30973774. REFERENCE #3: Ando Y, Okada F, Matsumoto S, Mori H. Thoracic manifestation of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA)-related disease. CT findings in 51 patients. J Comput Assist Tomogr. 2004 Sep-Oct;28(5):710-6. doi: 10.1097/01.rct.0000135280.79012.c7. PMID: 15480049. DISCLOSURES: No relevant relationships by Kyle Halligan, source=Web Response No relevant relationships by Jennifer Kodela, source=Web Response