PULMONARY ACTINOMYCOSIS PRESENTING AS A SUBCARINAL MASS IN A HEALTHY FEMALE

Abstract

Listen

Translate article

SESSION TITLE: Fellows Chest Infections Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: October 18-21, 2020 INTRODUCTION: Pulmonary actinomycosis, a rare chronic infection, is often misdiagnosed due to non-specific presentation. Here we present a case of a woman initially treated for aspiration pneumonia and histoplasmosis and was eventually found to have pulmonary actinomycosis on biopsy. CASE PRESENTATION: A healthy 38-year-old woman, 35-weeks-pregnant, was admitted for chest pain. Computerized tomography (CT) of the chest revealed a 4 cm subcarinal mass adjacent to the esophagus. Endobronchial ultrasound revealed multiple enlarged heterogeneous subcarinal lymph nodes. Transbronchial needle aspiration was negative for malignancy. The patient had an aspiration event 2 weeks prior to admission and completed a 14 day course of clindamycin. The mass significantly regressed radiographically after treatment. Upon follow-up, histoplasma antibody titer was positive at 1:32 (normal < 1:8) and she was started on a 3 month course of Itraconazole. Three months after discharge, she was readmitted for stabbing chest pain. CT chest re-demonstrated the subcarinal mass. Transbronchial needle aspiration specimens grew Actinomyces on tissue cultures. She was treated with a 4 month course of amoxicillin with complete resolution of symptoms and subcarinal mass on imaging. DISCUSSION: Actinomycosis is a slowly progressive granulomatous disease caused by actinomyces, a Gram–positive, filamentous microaerophilic bacterium. This bacteria normally colonizes the mouth and colon. Pulmonary actinomycosis is believed to be a result of inhalation or aspiration of oropharyngeal or upper gastrointestinal materials, and account for 15% of all actinomycosis cases. The clinical presentation, laboratory tests and radiological findings of pulmonary actinomycosis are non-specific, resulting in misdiagnosis with other chronic suppurative lung diseases and/or malignancies [1]. The infection can occur at all ages, with higher incidences in patients with poor oral hygiene, alcohol abuse disorder and underlying respiratory disorders. It starts as an acute inflammation followed by a chronic indolent phase with necrosis, fibrosis and pulmonary cavitation, and can progress to invasion of the pleura and chest wall [2]. There are no guidelines regarding the appropriate duration or route of antibiotic treatment; penicillin G for 2–6 weeks followed by oral penicillin or amoxicillin for 6-12 months, based on clinical and radiological response, has been the most common treatment regimen [3]. CONCLUSIONS: A high index of suspicion is required in order to diagnose pulmonary actinomycosis. Clinicians must be aware of its chronic and persistent presentation if left untreated, as early diagnosis will prevent significant physical and psychological morbidity. Reference #1: Farrokh D, Rezaitalab F, Bakhshoudeh B. Pulmonary actinomycosis with endobronchial involvement: a case report and literature review. Tanaffos. 2014; 13(1):52-6. Reference #2: Mabeza GF, Macfarlane J. Pulmonary actinomycosis. Eur Respir J. 2003; 21(3):545-51. Reference #3: Choi J, Koh WJ, Kim TS, et al. Optimal duration of IV and oral antibiotics in the treatment of thoracic actinomycosis. Chest. 2005; 128(4):2211-7. DISCLOSURES: No relevant relationships by Violeta Alvarez-Retamales, source=Web Response No relevant relationships by Moses Hayrabedian, source=Web Response No relevant relationships by Jessica Moja, source=Web Response No relevant relationships by Suhayb Ranjha, source=Web Response