[Emergent presence of slow-growing microorganisms in urine cultures. Clinical and microbiological analysis]

The prevalence, clinical characteristics, and antibiotic susceptibility of the slow-growing microorganisms Corynebacterium urealyticum, Corynebacterium glucuronolyticum, Lactobacillus delbrueckii, and Aerococcus spp. in urine cultures are analyzed.

Descriptive and retrospective cross-sectional study carried out in a Regional Hospital. Reports of clinical episodes with single isolation of the aforementioned microorganisms were selected between January 2016 and December 2023.

A total of 186 single-isolation episodes were included, corresponding to 0.44% of the total. The most frequently isolated species was Aerococcus urinae. Overall, the risk factors were the presence of an indwelling bladder catheter (24.73%), immunosuppression (24.19%), health care (35.48%), diabetes mellitus (19.89%), nephrourological disorders (31.18%) and previous antibiotherapy (35.48%). Urinary tract infections due to Aerococcus spp. predominated in elderly patients, with nephrourological disorders and a history of antibiotic therapy in the previous 3 months. C. glucuronolyticum, C. urealyticum and L. delbrueckii were associated with immunosuppression, healthcare contact and previous antibiotherapy. C. urealyticum was also associated with the presence of an indwelling bladder catheter.

Slow-growing opportunistic emerging microorganisms represent a small percentage of the aetiological agents in urinary tract infections, although of important and growing clinical interest given their pathogenic role in the presence of certain circumstances and risk factors, as well as the challenges they pose for laboratory diagnosis. It is essential to perform antibiograms for an adequate targeted treatment.