A Domestic Outbreak of Bacterial Dysentery Caused by Extended-Spectrum beta-Lactamase (ESBL) -producing Shigella sonnei

Lim, Hyun Taek; Lee, So Hee; Lee, Jung Hwa; Kim, Jeong Eun; Kim, Kyo Sun; Jeong, Eun Ju; Lee, Seung Hyun; Kang, Chang Gyu; Hong, Seong Jin

Abstract

PURPOSE
An outbreak of ESBL-producing Shigella sonnei enteritis was unprecedented not only in Korea but throughout the world in the past. We intended to devise a management guideline for ESBL-producing shigellosis based on analysis of clinical manifestations and response to therapy. METHODS: We analyzed 103 patients who were admitted to the hospital with acute GI symptoms and were shown positive result for S. sonnei on stool culture. We performed sensitivity test to the antibiotics and DNA sequencing of ESBL gene in the isolated S. sonnei colonies. In addition, we retrospectively analyzed their clinical characteristics, laboratory results, and clinical and microbiological responses to the antibiotics. RESULTS: Among the clinical manifestations, fever was the most frequent (96.1%), followed by diarrhea (93.2%), abdominal pain (76.7%), headache (71.8%), vomiting (65.0%), and nausea (41.7%). The fever was sustained for average of 2.0 days and diarrhea for 3.9 days. Watery diarrhea was the most common (69%) followed by mucoid (26%), and bloody stool (5%). On peripheral blood smear, leukocytosis was noted in 53.4% of patients, and 78.6% of patients tested positive for serum CRP response. On stool direct smear, 11.7% of patients showed more than 50 WBCs/HPF, and 9.7% of patients between 5 to 20 WBCs/HPF. Stool occult blood was positive in 71% of patients. Production of CTX-M-14 type ESBL was reported for all S. sonnei strains isolated from this outbreak. Microbiological eradication rates to various antibiotics were as follows: 100% (9/9) to ciprofloxacin, 100% 5/5) to azithromycin, 6.9% (5/72) to cefdinir, 0% (0/8) to ceftriaxone, 12.5% (1/8) to ceftizoxime, 0% (0/ 8) to TMP/SMX, 42.9% (3/7) to ampicillin/sulbactam, 20% (1/5) to amoxicillin/clavulanic acid, and 68.8 % (11/16) to imipenem/cilastatin. CONCLUSION: It is presumed that azithromycin can be an attractive option for the treatment of ESBL-producing S. sonnei enteritis in pediatric population, given its cost-effectiveness and safety. Although ciprofloxacin is another cost-effective agent, its use in pediatric population may be a bit too premature.