Isolation of thymidine-dependent and extended-spectrum-β-lactamase-producing Escherichia coli small-colony variant from urine of a septuagenarian female patient with recurrent cystitis: A case report with genetic investigation

Autor: Takehisa Matsumoto, Yoshiyuki Kawakami, Tetsuro Sugiura, Koichi Tanimoto, Natsumi Nagano, Konosuke Yamamoto, Hideyasu Honjyo, Atsuaki Takada, Megumi Nagata, Masami Kashihara
Rok vydání: 2020
Předmět:
Zdroj: Journal of Infection and Chemotherapy. 26:1066-1069
ISSN: 1341-321X
DOI: 10.1016/j.jiac.2020.05.013
Popis: Thymidine-dependent small-colony variant (TD-SCV) of Escherichia coli was isolated from urine of a septuagenarian female patient on hemodialysis suffering from recurrent cystitis. The patient had been treated with frequent administrations of trimethoprim sulfamethoxazole (SXT), every time her cystitis symptoms developed. In the TD-SCV isolate, the deletion was detected in the thyA gene associated with thymidylate synthase. Interestingly, the isolate was found to produce extended-spectrum β-lactamase (ESBL), and the experiment on conjugational transfer of the resistance trait was successful. By means of genetic analysis, the isolate was found to carry blaCTX-M-1 group. To the best of our knowledge, this is the first report of urinary tract infection caused by the transmissible ESBL-producing TD-SCV of E. coli. MICs of the TD-SCV were obtained only on the Mueller Hinton agar media supplemented with appropriate concentrations of thymidine, which might lead to the difficulty for proper chemotherapy in daily medicine. Furthermore, transmission of the ESBL gene via plasmid should be of concern.
Databáze: OpenAIRE
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