Clinical assessment of a spp. polymerase chain reaction (PCR)-based assay for the diagnosis of nocardiosis.

Fiche publication

Date publication

mars 2018

Journal

Journal of clinical microbiology

Auteurs

Membres identifiés du Cancéropôle Est :
Dr LAROSA Fabrice

Tous les auteurs :
Rouzaud C, Rodriguez-Nava V, Catherinot E, Méchaï F, Bergeron E, Farfour E, Scemla A, Poirée S, Delavaud C, Mathieu D, Durupt S, Larosa F, Lengelé JP, Christophe JL, Suarez F, Lortholary O, Lebeaux D

Lien Pubmed

https://www.ncbi.nlm.nih.gov/pubmed/29563199

Résumé

Diagnosis of nocardiosis, a severe opportunistic infection, is challenging. We assessed the specificity and sensitivity of a 16S PCR-based assay performed on clinical samples. In this multicenter study (January 2014 - April 2015), patients admitted to three hospitals who had an underlying condition favoring nocardiosis, clinical/radiological signs compatible with nocardiosis and a PCR performed on a clinical sample were included. Patients were classified as negative control (NC: negative culture for and proven alternative diagnosis or improvement at 6 months without anti- treatment); positive control (PC: positive culture for ); or probable nocardiosis (positive PCR, negative culture for no alternative diagnosis). Sixty-eight patients were included: 47 were classified as NC, 8 as PC, 13 as probable nocardiosis. PCR was negative in 35/47 (74%) NC patients. In the 12 NC patients with a positive PCR, the PCR had been performed on respiratory samples. These NC patients more frequently had chronic bronchopulmonary disease than did the NC patients with a negative PCR (8/12 [67%] vs 11/35 [31%], p=0.044). PCR was positive in 7 of the 8 PC patients (88%). There were 13 cases of probable nocardiosis, diagnosed solely using the PCR result; 9 of these patients (69%) had lung involvement (consolidation or nodule). PCR had a specificity of 74% and a sensitivity of 88% for diagnosis of nocardiosis. PCR may be helpful for diagnosis of nocardiosis in immunocompromised patients but interpretation of PCR results from respiratory samples is difficult, because the PCR assay may also detect colonization.