Article in Japanese

A case of shigellosis by extended-spectrum ß-lactamase (ESBL) producing Shigella sonnei：an outbreak at a nursery school in Aichi Prefecture

Yuta SUDO^1） , Fumihiko HATTORI^1） , Yumiko ASAI^1） , Natsuki HATAKAWA^1） , Yuka MIHARA^1）

Extended-spectrum ß-lactamase (ESBL)-producing Shigella sonnei infections are reported worldwide. However, owing to their rarity in Japan, clinical features and antimicrobial treatment against this infection currently remain unknown.
This paper reports the case of a four-year-old boy with ESBL-producing S. sonnei infection, who developed it following a small outbreak of S. sonnei at a day-care nursery he attended in Aichi prefecture. He presented with fever, vomiting and bloody stool and was admitted to this hospital with a diagnosis of acute bacterial enteritis. A stool culture performed at the time of admission showed negative results; however, an outbreak of shigellosis was confirmed in the day-care nursery on the 4^th day of hospitalization. Repeat stool culture yielded ESBL-producing S. sonnei. Based on the results of drug susceptibility tests, specific antibiotic was administered, and the patient was discharged following improvement on the 8^th day of hospitalization. Further bacteriological investigation of stool specimens, obtained from 181 children at the nursery, 52 of their family members, and 44 staff members (277 individuals), revealed S. sonnei in 18 cases；however, the source of infection was not identified. Most of the patients were asymptomatic or presented with mild symptoms. Antibiotics were administered to eight patients with gastrointestinal symptoms. Fosfomycin was administered to six patients, and eradication of infection was confirmed in all of them, which suggests the usefulness of fosfomycin for ESBL-producing S. sonnei infection.

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1）Department of Pediatrics, Kariya Toyota General Hospital

Key words	ESBL producing, Shigella sonnei, shigellosis, nursery school, outbreak
Received	October 31, 2022
Accepted	November 17, 2022

34 (4)：291─299,2022