Infection à Nocardia farcinica chez un patient porteur d’une mucoviscidose [Nocardia farcinica infection in a patient with cystic fibrosis].
Résumé
Infections by Nocardia species are uncommon and generally affect immunocompromised patients. This bacteria has rarely been isolated from cystic fibrosis patients (CF), especially those who are not taking oral corticosteroids. We report a case of a patient with CF harbouring Nocardia farcinica. An 18-year-old male diagnosed with CF at the age of eight (F508 del/G85E) had been treated for allergic bronchopulmonary aspergillosis in 1998 with itraconazole, and a first colonization with Pseudomonas aeruginosa was eradicated in 2003. From May 2006, he presented with recurrent left- and right-sided pneumothorax. In June 2006, he presented with dyspnoea, fever, and nodular eruption on his ankles. Chest X-ray and CT scan revealed a right pneumothorax, severe bronchiectasis and bilateral alveolar consolidation. N. farcinica was idolated from his sputum without any other pathogens. Treatment with intravenous cotrimoxazole associated with imipenem and amikacin was initiated for three weeks followed by oral cotrimoxazole for a further nine months. The patient's symptoms and alveolar consolidation on CT scan improved. During 2007, his respiratory condition worsened and his FEV(1) declined from 50 to 26 % predicted. His pneumothorax recurred. He had chronic colonization with P. aeruginosa and was on the list for lung transplantation. Nocardia, a Gram positive bacillus, causes mainly pulmonary infection, usually in the context of immune suppression. The most frequent species is N. asteroides. In CF, very few cases have been reported; almost always N. asteroides, but exceptionally N. farcinica. In CF patients with worsening pulmonary condition, Nocardia should be considered, as well as other unusual pathogens.