16S rRNA PCR on clinical specimens: Impact on diagnosis and therapeutic management

•Our study demonstrated that 16S PCR was helpful for 28.8% of patients. It led to antibiotic therapy changes in 4.5% of patients.•Despite a lack of sensitivity, 16S PCR is sometimes the last resort for identifying bacterial pathogens.•Physicians should be aware of the performances of this tool for appropriate interpretation of results.•Case-by-case discussion between physicians and bacteriologists is essential for selecting indications for 16S PCR as well as for result interpretation. 16S rRNA PCR (16S PCR) performed on clinical samples contributes to bacterial identification in cases of negative culture due to an antibiotic therapy. Sensitivity of the 16S PCR is low (19–42%). Little data is available on its impact on the management of patients. We aimed to evaluate the contribution of 16S PCR to diagnosis and therapeutic management at the university hospital of Dijon, France. 16S PCR was performed on the clinical specimens of 132 patients. Clinical settings, laboratory results, and data on antibiotic therapy were collected, as well as conclusions drawn from the 16S PCR result by physicians. Each case was analyzed to determine if the 16S PCR was helpful. The relevance of the 16S PCR was also assessed. The 16S PCR yield was 27.3%, ranging from 14.3% to 64.3% depending on the type of specimen. 16S PCR had a positive impact on diagnosis in 28.8% of cases. Five negative 16S PCR results were considered helpful as they contributed to ruling out bacterial infection. 16S PCR led to treatment changes in six patients (4.5%): three narrower spectrums, two treatment adaptations, and one discontinuation. The 16S PCR was considered “non-relevant” in 35 cases (26.5%). None of these 35 PCRs contributed to the patient's management. Physicians should be aware of performances of 16S PCR. Dialogue between physicians and bacteriologists is essential for appropriate selection of indications and correct interpretation of results. La PCR ARNr 16S (PCR 16S) sur échantillons cliniques permet l’identification bactérienne en cas d’infection décapitée. Sa sensibilité est faible (19–42 %). Son impact sur la prise en charge des patients a été peu étudié. L’objectif de cette étude était d’évaluer l’utilité de la PCR 16S sur les plans diagnostique et thérapeutique au CHU de Dijon. Une PCR 16S a été réalisée sur des échantillons prélevés chez 132 patients. Les données cliniques, biologiques et thérapeutiques ont été recueillies, ainsi que l’interprétation des résultats de PCR 16S par les c