A Case of Urinary Tract Infection Caused by Multidrug Resistant Streptococcus mitis/oralis

Abstract

S. mitis/oralis has been previously reported in isolated cases of bacterial endocarditis and liver abscesses. Its presence in urine is generally considered a contaminant. A 66-year-old male patient was admitted to the hospital due to recurrent chest tightness and four-year history of exertional dyspnea. On the second day of admission, the patient presented with urgent and frequent urination, as well as dysuria. Both initial and subsequent urine cultures showed S. mitis/oralis infection, with polymorphonuclear leukocyte phagocytosis observed in the second sample. MALDI-TOF results confirmed the isolated strain as S. mitis/oralis. Drug susceptibility testing revealed multidrug resistance to penicillin, ceftriaxone, cefepime, levofloxacin, ofloxacin, and tetracycline, but sensitivity to quinupristin/dalfopristin, vancomycin, and linezolid. The clinician then prescribed vancomycin for anti-infective treatment, which proved effective. Keywords: S. mitis/oralis, UTI, MDR, phagocytosis

Keywords:

• Streptococcus mitis/oralis
• UKI
• multidrug resistant
• phagocytosis

Data Sharing Statement

The datasets used and analyzed during the current study are available from the corresponding author Dr. Shucai Yang on reasonable request.

Ethics Statement

Human Ethics approval was obtained from the Pingshan General Hospital of Southern Medical University Committee and the study was performed in accordance with the 1964 Declaration of Helsinki. Informed consent for publication of the personal information and clinical data have been obtained from the patient.

Acknowledgment

We thank Wengrong Kang and Juan Zhang for their technical assistance.

Disclosure

The authors report no conflicts of interest in this work.

Additional information

Funding

This study was supported by grants from the National Natural Science Foundation of China (No.82272986 to SY), the Natural Science Foundation of Guangdong Province, China (No.2023A1515010230 to SY), the Science and Technology Foundation of Shenzhen (No.JCYJ20220531094805012 to SY), the Project of Educational Commission of the Guangdong Province of China (No.2022KTSCX022 to JZ), and the National Key R&D Program of China (No.2020YFC2006400 to TF).