Use of organism identification by 16S ribosomal RNA polymerase chain reaction to shorten antimicrobial length of therapy

BACKGROUND:Organism detection by 16S ribosomal RNA (rRNA) PCR followed by amplicon sequencing identification may help guide antimicrobial treatment in culture-negative patients. The objectives of this study were to assess the effect of a positive versus negative 16S rRNA PCR on antibiotic length of therapy (LOT) and rate of antibiotic discontinuation. METHODS:Patients with a sterile site, direct-specimen 16S rRNA PCR negative, and suspected active infection were matched 1:1 with 16S rRNA PCR positive patients based on specimen site and retrospectively evaluated. RESULTS:Ninety patients were included (n=45 positive and negative). 16S rRNA PCR negative patients had shorter median LOT (33days [IQR 8-46] versus 43days [IQR 29-51], P=0.02). Antibiotics were discontinued more frequently in 16S rRNA PCR negative patients (38% versus 4%, P<0.01). CONCLUSIONS:For culture-negative patients with suspected sterile site infection, a negative, direct-specimen 16S rRNA PCR may help discontinue antibiotics and decrease LOT.