AN OBSTACLE AROUND THE CORNER

Abstract

SESSION TITLE: Medical Student/Resident Chest Infections Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Post obstructive pneumonia (POP) is found in 2-5% of patients with community acquired pneumonia (CAP), characterized by infection distal to a mechanical obstruction of the bronchus. Post obstructive pneumonia is in the differential diagnosis in patients with recurrent infections in the same lung segment(s). Bronchoscopic intervention is usually diagnostic and may also be therapeutic in certain cases. We present a case of post obstructive pneumonia which was later found to be secondary to foreign body aspiration. CASE PRESENTATION: A 60-year old woman was admitted to the hospital for recurrent right lower lobe pneumonia. She endorsed cough with dark green sputum, shortness of breath, drenching night sweats and a 30lb unintentional weight loss in the preceding 6 months. She had a history of recurrent pneumonias for the past eighteen months, with chest imaging that revealed similar right lower lobe infiltration. On physical examination she was afebrile with unremarkable vital signs. Auscultation revealed right lower lobe crackles. Procalcitonin was 0.06 ng/mL and WBC was 10.32. A CT chest demonstrated a right lower lobe infiltrate and possible endobronchial lesion. (Figure 1) Due to concern for endobronchial mass, bronchoscopy was performed which revealed a mobile obstructing mass in the right lower lobe that was retrieved with forceps. There was moderate amount of purulent secretion distal to the obstruction. (Figure 2) Pathology revealed “probable vegetable matter” (Figure 3) and bronchoalveolar lavage (BAL) cultures grew Streptococcus Sanguinis. She was discharged with amoxicillin/clavulanic acid. DISCUSSION: In patients with recurrent pneumonia in the same lung segment, the differential is broad and includes post obstructive pneumonia (POP), ”non-resolving pneumonia” (due to infectious and non-infectious causes) and aspiration. In patients with POP, the most common etiology of obstruction is malignancy, including malignant and benign tracheobronchial tumors. [1,3] The microbiology is diverse and spans gram positive, gram negative and anerobic bacteria thus broad coverage is often initially indicated. [2] Features that distinguish POP from CAP include a lower likelihood of leukocytosis, bandemia, elevated procalcitonin, or fever. With POP there is often >5% weight loss and have increased duration of symptoms. [1] Foreign body aspiration in adults occurs with swallowing disorders of varying etiologies and in states of impaired consciousness. Food causes a more prominent inflammatory reaction (acute and chronic bronchus inflammation in our patient) compared with inorganic objects. CONCLUSIONS: In a patient with recurrent pneumonia in the same lung segment with constitutional symptoms consider post obstructive pneumonia. Workup and treatment includes CT imaging, bronchoscopy and antibiotics. Reference #1: Abers, M.S., et al., Postobstructive Pneumonia: An Underdescribed Syndrome. Clin Infect Dis, 2016. 62(8): p. 957-61. Reference #2: Rolston, K.V.I. and L. Nesher, Post-Obstructive Pneumonia in Patients with Cancer: A Review. Infect Dis Ther, 2018. 7(1): p. 29-38. Reference #3: Stevic R, Milenkovic B. Tracheobronchial tumors. J Thorac Dis. 2016;8(11):3401–3413. DISCLOSURES: No relevant relationships by Giuliana Cerro, source=Web Response No relevant relationships by George Chaux, source=Web Response No relevant relationships by Michael Lewis, source=Web Response No relevant relationships by Jason Wong, source=Web Response