title: Pulmonary Mycobacterium marinum infection: 'fish tank granuloma' of the lung.
abstract: A 65-year-old man presented with a six-month history of lethargy, weight loss and dry cough. He had a background of mild chronic obstructive pulmonary disease. Chest radiograph showed new right upper lobe cavitary opacification. Sputum cultures were acid-fast bacilli smear positive and yielded Mycobacterium marinum - a non-tuberculous mycobacterium (NTM) often found in aquatic environments and rarely associated with respiratory disease. The suspected source was silent aspiration of contaminated water, likely due to his initiating the siphon of his fish-tank by mouth. He completed a one-year course of rifampicin, ethambutol and clarithromycin, with negative repeat sputum mycobacteria cultures and radiological improvement. This case report demonstrates a successful approach to investigation and further management of Mycobacterium marinum pulmonary disease - a rare condition, particularly in immunocompetent individuals, with limited treatment guidelines.
authors.affiliation: Respiratory Specialist Registrar, Royal Infirmary of Edinburgh, UK prasad.velu@nhslothian.scot.nhs.uk.
authors.forename: Prasad Palani
authors.initials: PP
authors.lastname: Velu
authors.affiliation: Respiratory Specialist Registrar, Royal Infirmary of Edinburgh, UK.
authors.forename: Susan E
authors.initials: SE
authors.lastname: Fernandes
authors.affiliation: Director, Scottish Mycobacteria Reference Laboratory, Royal Infirmary of Edinburgh, UK.
authors.forename: Ian F
authors.initials: IF
authors.lastname: Laurenson
authors.affiliation: Consultant Respiratory Physician, St John's Hospital, Livingston, UK.
authors.forename: Donald D
authors.initials: DD
authors.lastname: Noble
mesh_terms: D000368:Aged; D000818:Animals; D000904:Antibiotics, Antitubercular / Q000627:therapeutic use; D017291:Clarithromycin / Q000627:therapeutic use; D003371:Cough; D004977:Ethambutol / Q000627:therapeutic use; D005399:Fishes / Q000382:microbiology*; D006801:Humans; D053609:Lethargy; D008297:Male; D009165:Mycobacterium Infections, Nontuberculous / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications; D012293:Rifampin / Q000627:therapeutic use; D016896:Treatment Outcome; D062065:Wastewater / Q000382:microbiology*; D015431:Weight Loss
chemical_list: D000904:Antibiotics, Antitubercular; D017291:Clarithromycin; D004977:Ethambutol; D012293:Rifampin; D062065:Wastewater
keywords: Pulmonary; infection; non-tuberculous mycobacteria