• Journal of Microbiology
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• 제43권2호
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• pp.133-143
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• 2005

Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These species are subdivided into serotypes on the basis of O-specific polysaccharide of the LPS. Shigella dysenteriae type 1 produces severe disease and may be associated with life-threatening complications. The symptoms of shigellosis include diarrhoea and/or dysentery with frequent mucoid bloody stools, abdominal cramps and tenesmus. Shigella spp. cause dysentery by invading the colonic mucosa. Shigella bacteria multiply within colonic epithelial cells, cause cell death and spread laterally to infect and kill adjacent epithelial cells, causing mucosal ulceration, inflammation and bleeding. Transmission usually occurs via contaminated food and water or through person-to-person contact. Laboratory diagnosis is made by culturing the stool samples using selective/differential agar media. Shigella spp. are highly fragile organism and considerable care must be exercised in collecting faecal specimens, transporting them to the laboratories and in using appropriate media for isolation. Antimicrobial agents are the mainstay of therapy of all cases of shigellosis. Due to the global emergence of drug resistance, the choice of antimicrobial agents for treating shigellosis is limited. Although single dose of norfloxacin and ciprofloxacin has been shown to be effective, they are currently less effective against S. dysenteriae type 1 infection. Newer quinolones, cephalosporin derivatives, and azithromycin are the drug of choice. However, fluoroquinolone-resistant S. dysenteriae type 1 infection have been reported. Currently, no vaccines against Shigella infection exist. Both live and subunit parenteral vaccine candidates are under development. Because immunity to Shigella is serotype-specific, the priority is to develop vaccine against S. dysenteriae type 1 and S. flexneri type 2a. Shigella species are important pathogens responsible for diarrhoeal diseases and dysentery occurring all over the world. The morbidity and mortality due to shigellosis are especially high among children in developing countries. A recent review of literature (KotIoff et al.,1999) concluded that, of the estimated 165 million cases of Shigella diarrhoea that occur annually, $99\%$ occur in developing countries, and in developing countries $69\%$ of episodes occur in children under five years of age. Moreover, of the ca.1.1 million deaths attributed to Shigella infections in developing countries, $60\%$ of deaths occur in the under-five age group. Travellers from developed to developing regions and soldiers serving under field conditions are also at an increased risk to develop shigellosis.

• Childhood Kidney Diseases
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• 제10권2호
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• pp.244-248
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• 2006

Shigella infection usually produces gastrointestinal symptoms but rarely causes urinary tract infection. A 7-year-old girl was admitted for fever, chills, right flank pain, and dysuria. She had no vomiting or diarrhea. There was mild tenderness in her right lower abdomen, and right CVA tenderness was also noted. Acute pyelonephritis was diagnosed by abdominal CT. She showed improvement with intravenous administration of antibiotics. The first urine culture grew $1{\times}10^5$ CFU/mL Shigella dysenteri. Although urinary tract infections due to Shigella species are extremely rare, Shigella species should be considered as a possible cause of pediatric urinary tract infection. We report the first case of urinary tract infection caused by S. dysenteri, which presented as acute pyelonephritis without gastrointestinal symptoms in a child.

• IMMUNE NETWORK
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• 제14권2호
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• pp.100-106
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• 2014

Infection with invasive Shigella species results in intestinal inflammation in humans but no symptoms in adult mice. To investigate why adult mice are resistant to invasive shigellae, 6~8-week-old mice were infected orally with S. flexneri 5a. Shigellae successfully colonized the small and large intestines. Mild cell death was seen but no inflammation. The infected bacteria were cleared 24 hours later. Microarray analysis of infected intestinal tissue showed that several genes that are involved with the sphingosine-1-phosphate (S1P) signaling pathway, a lipid mediator which mediates immune responses, were altered significantly. Shigella infection of a human intestinal cell line modulated host S1P-related genes to reduce S1P levels. In addition, co-administration of S1P with shigellae could induce inflammatory responses in the gut. Here we propose that Shigella species have evasion mechanisms that dampen host inflammatory responses by lowering host S1P levels in the gut of adult mice.

• 대한미생물학회지
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• 제22권4호
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• pp.453-462
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• 1987

A total of 3,879 cases of feces and rectal swab from patient was collected in H. hospital from January 1974 to December 1986 in Seoul. Among the materials, the number of cases of Shigella spp. isolated were 197 strains of 139 patients. Infectous pattern and antibiotic sensitivity of Shigella spp. were as follows; The range of percentage of an identified Shigella spp. among total feces and rectal swabs was $1.5{\sim}12.5%$ yearly. The isolation ratios of Shigella spp. per each patient 1.35 for male and 1.19 for female. The isolation ratio of male to female was 1.28:1 in whole group. The isolated Shigella species was 81.0% in S. flexneri, 1.1% in S. boydii and 17% in S. sonnei. The highest number of Shigella spp. was found in August and September according to monthly isolation, on the other hand the lowest number of Shigella spp. was obserbed in March. The seasonal isolation rate of Shigella spp. was 31.7% in Fall, 27.3% in Summer, 21.6% in Winter and 19.3% in Spring. The age specific frequency of Shigellosis was 46.8% in $0{\sim}9$ year group, 8.6% in $10{\sim}19$, 7.2% in $40{\sim}49$ and 6.5% in $50{\sim}59$. The antibiotics showing over 80% susceptibility against Shigella spp. were gentamicin, kanamycin, amikacin, tobramycin, cefoperazone, cefoxitin, cefamandole nafate, cefotaxine and sisomycin.

• Journal of Microbiology and Biotechnology
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• 제22권8호
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• pp.1113-1117
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• 2012

Shigella sonnei is a causal agent of fever, nausea, stomach cramps, vomiting, and diarrheal disease. The present study describes a quantitative polymerase chain reaction (qPCR) assay for the specific detection of S. sonnei using a primer pair based on the methylase gene for the amplification of a 325 bp DNA fragment. The qPCR primer set for the accurate diagnosis of Shigella sonnei was developed from publically available genome sequences. This quantitative PCR-based method will potentially simplify and facilitate the diagnosis of this pathogen and guide disease management.

• 약학회지
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• 제34권1호
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• pp.54-63
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• 1990

These studies were made to assess the present stage of resistance of Shigella species to antibiotics and to find characteristics of R-plasmid of these bacteria. From 1986 to 1988, 125 strains of Shigella species were isolated from patients specimens collected in Chung Cheong-do Hospital, Kyunghee Medical Center, city an provincial health & environmental institutes. These specimens were tested for resistance to 12 kinds of antimicrobial agents by agar dilution method. Using Muller-Hinton agar for the assay of drug resistance and Trypticane Soy Broth as propagating medium for conjugation. All the strains (100%) were resistant to one or more antibiotics. Drug resistance patterns of isolated strains were found as the highest resistance to ampicillin (98%) in 1986, to tetracycline (98%) in 1987, to tetracycline (100%) in 1988, all strains were sensitive to gentamicin, amikacin, tobramycin. Chronologically, resistance decreased gradually as it was shown in relation to kanamycin, rifampicin in 1986, 1987 and 1988, (4%, 2%) (4%, 2%) (0%, 0%) respectively. But, resistance was increased year by year as it was shown in relation to tetracycline, nalidixic acid, streptomycin in 1986, 1987, 1988 (89%, 19%, 45%) (98%, 46%, 71%) and (100%, 58%, 88%). The resistance in correlation to more than 5 drugs, which was 13 strains among 47 strains in 1986, 38 strains among 87 strains in 1987, 23 strains among 26 strains in 1988, was increased gradually. In the transfer test of drug resistance by conjugation methods, the rate which was 3 strains (50%) in 1986, 8 strains (62%) in 1987, 3 strains (100%) in 1988, was increased gradually. When the donor strains were conjugated with the recipient strains, the conjugation rate was high in the multiple resistant strains. The relationships of transferring patterns of drug resistance and molecular weight of R-plasmid were variable. However, only a plasmid which has more than 35 Mgd was transferred.

• 대한미생물학회지
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• 제21권4호
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• pp.417-422
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• 1986

The specimens were collected from 89 diarrheal patients who had visited Pusan National University Hospital from June to September 1985. They were cultured and tested for the bacteriological identification of causative agents. In this study we identified 5 strains of Salmonella species, 5 strains of Shigella species, 2 strains of Y. enterocolitica, and 17 strains of enteric pathogenic E. coli. Enteric pathogenic E. coli were classified into enterotoxigenic E. coli, enteropathogenic E. coli, and enteroinvasive E. coli by serological type. We tried to isolate V. cholerae and V. parahaemolyticus too but we cannot find them out.

• 대한미생물학회지
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• 제21권4호
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• pp.461-471
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• 1986

1973년부터 1985년 사이에 대구지방에서 분리된 Shigella는 약 1,200주였는데, 대부분이 Shigella flexneri였고, S. sonnei는 약 20%였으며, S. dysenteriae와 S. boydii는 극히 적었다. 분리균의 95%이상이 chloramphenicol(Cm), tetracycline(Tc), streptomycin(Sm), sulfisomidine(Su), ampicillin(Ap), trimethoprim(Tf) 등의 전부 또는 일부 약제에 내성이었으며, kanamycin, nalidixic acid(Na)와 rifampin(Rf)에 내성인 균주는 소수 있었으나, cephaloridine, gentamicin, amikacin 등에 내성인 균주는 없었다. 1973년에 분리된 균은 약 절반이 약제내성이었으나, 1977년 이후 분리된 균은 95% 이상이 약제내성이었다. 1977년 까지는 Cm, Tc, Sm 및 Su의 4제 내성균이 가장 많았으나 1978년 부터는 Cm, Tc, Sm, Su, Ap 및 Tp의 6제 내성균이 가장 많았다. 약 75%의 균이 그 약제내성을 접합에 의하여 Escherichia coli에 전달하였으므로 이 약제내성은 R plasmid에 의한 것으로 생각되었다. 대다수의 균에 있어서 약제내성 전부를 E. coli에 전달하였으나, Na와 Rf의 내성은 전달되지 않았다. 일부 균주의 약제내성은 E. coli에 전달될 때 분리되는 일이 있었으나, 그 수는 극히 적었다. Shigella의 R Plasmid는 대부분이 비적합성군(incompatibility group) F II에 분류되었으나, 극소수는 B군에 속하였고 군별이 안되는 것도 있었다.

• 대한미생물학회지
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• 제15권1호
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• pp.33-38
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• 1980

Shigella remains to be an important enteric pathogen in this country for the moment. Moreover, since 1978, most of the isolates have become resistant to ampicillin and co-trimoxazole, which used to be the drugs of choice for shigellosis. Since a disc diffusion technique alone has been used in our routine susceptibility test, the minimum inhibitory concentrations(MIC) of both ampicillin and co-trimoxazole to Shigella have never been known. In order to determine these, 195 isolates were tested by an agar dilution method, all of which were isolated at Yonsei Medical Center during the period of June 1978 to July 1980. The following results were obtained. 1. Sixty cultures(29.7%) were susceptible to ampicillin, being the MIC of 8 ${\mu}g/ml$ or less and 53(27.2%) were susceptible to co-trimoxazole, being the MIC of TMP/SMZ 4/76 ${\mu}g/ml$ or less. S. flexneri type 2 was often resistant to both antimicrobic agents. 2. An increasing rate of resistant isolates was noted, particularly in the year of 1979. 3. Many isolates were resistant to both agents. Somewhat more cultures. were ampicillin susceptible and co-trimoxazole resistant than the other way around. It seems that the determination of species or even serotypes might be of help sometimes to select proper antimicrobic agent to control the infection. A routine antimicrobic susceptibility test of Shigella to both ampicillin and co-trimoxazole would be advisable for a better selection of chemotherapeutic agent.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제25권1호
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• pp.41-51
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• 2022

Purpose: Community-acquired bacterial enteritis (CABE) is a common problem in developed countries. It is important to understand the epidemiologic changes in bacterial pathogens for prevention and treatment. Therefore, we studied the epidemiologic changes in CABE in Korean children. Methods: A total of 197 hospitalized pediatric patients aged <19 years that presented with dysentery symptoms and showed positive polymerase chain reaction results for bacterial species in stool samples, were enrolled in this study for 10 years (June 2010 to June 2020). We classified patients in phase I (06, 2010-06, 2015) and phase II (07, 2015-06, 2020) and analyzed their epidemiologic and clinical characteristics. Results: The most common pathogens were Campylobacter species (42.6%) and Salmonella species were the second most common pathogens (23.9%). The abundance of pathogens decreased in the following order: Clostridium difficile (9.6%), Shigella (5.6%), and Clostridium perfringens (5.6%). Escherichia coli O157:H7 was found to be the rarest pathogen (2.0%). Campylobacter species showed an increase in the infection rate from 32.1% in phase I to 49.6% in phase II (p=0.0011). Shigella species showed a decline in the infection rate in phase I from 14.1% to 0.0% in phase II (p<0.001). C. difficile and C. perfringens showed an increase in infection rate in phase II compared to phase I, but the difference was not statistically significant. Conclusion: The infection rate of Campylobacter species in CABE has been rising more recently, reaching almost 50%. This study may help establish policies for prevention and treatment of CABE in Korean children.