title: Pulmonary infection with caseating mediastinal lymphadenitis caused by Mycobacterium gordonae.
abstract: It is often difficult to discern true mycobacterial infection from colonization due to Mycobacterium gordonae (M. gordonae) since this organism is ubiquitous and is commonly an innocuous saprophyte. This study reports a rare case of caseating hilar adenopathy and pulmonary disease caused by M. gordonae in a patient with chronic obstructive pulmonary disease (COPD) and rheumatoid arthritis (RA) on maintenance steroids and methotrexate. Pathologic exam and cultures of lymph node excision biopsy and bronchoalveolar lavage (BAL) confirmed the diagnosis. Triple antimycobacterial therapy with azithromycin, ethambutol and rifabutin was administered. The patient had significant clinical and radiologic improvement and follow-up cultures confirmed microbiologic cure. Mycobacterium gordonae can be a rare cause of significant pulmonary infection, and positive sputum or BAL cultures for M. gordonae should not be automatically discarded and considered as nonpathogenic contaminants or colonizing organisms, especially in immunocompromised hosts with comorbidities. A detailed review of the case and relevant literature is provided.
authors.affiliation: Department of Medicine, Division of Infectious Diseases, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States. Electronic address: estecina@hotmail.com.
authors.forename: Dima
authors.initials: D
authors.lastname: Youssef
authors.affiliation: Department of Medicine, Division of Infectious Diseases, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States; James H. Quillen Veterans Affairs Medical Center, Mountain Home, TN 37684, United States.
authors.forename: Wael E
authors.initials: WE
authors.lastname: Shams
authors.affiliation: Department of Pathology, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States.
authors.forename: Yasmin
authors.initials: Y
authors.lastname: Elshenawy
authors.affiliation: Department of Medicine, Division of Pulmonary/Critical Care, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States.
authors.forename: Adel
authors.initials: A
authors.lastname: El-Abbassi
authors.affiliation: Department of Medicine, Division of Infectious Diseases, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, United States; James H. Quillen Veterans Affairs Medical Center, Mountain Home, TN 37684, United States.
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Moorman
keywords: Caseating granuloma; Immunocompromised; Infection; Lung disease; Mycobacterium gordonae