Changing Patterns of Salmonella Infection & Changes In Antimicrobial Resistance of Salmonella strains Isolated in 1987-1995

Chang, Sang Pil; Lee, Sang Ho; Kim, Koo Yeop; Suh, Hwan Jo

Abstract

OBJECTIVES
Salmonellosis is one of the most common bacterial infections in the Korea. The incidence of salmonellosis has changed dramatically. The incidence of typhoid fever tends to decrease as environmental & personal sanitations improve, whereas that of nontyphoid salmonellae have markedly increased. Antimicrobial resistance is increasing in Salmonella strains. Increasing emergence in multiple-drug resistant Sallmonella strains has important clinical & public implications for populations at risk and the treatment of invasive salmonellosis is complicated by the increasing resistance among Salmonella strains to commonly used antimicrobial agents. This study is performed to fine out the pattern and the antimicrobial susceptibility of isolated Salmonella strains and the clinical charateristics of Salmonella infection.
METHODS
We reviewed medical records of all patients with culture-confirmed Salmonella infection in Kyung Hee University Hospital for the period January 1987 through December 1995.
RESULTS
1) The mean age of the patients was 31.0 years and the ratio of male to female was 1.03:1. 2) The frequency of isolation of specific serogroups is ordered as followings : serogroup B(47.9%), serogroup D(23.3%), S. typhi(16.2%), serogroup C(9.6%), serogroup E(1.8%), serogroup A(1.2%). 3) The sites of isolation were as follows : stool(68.6%), blood(24.0%), pus(3.5%), urine(2.2%), bone marrow(2.2%), bile juice(0.4%), ascites(0.4%), CSF(0.2%), sputum(0.2%). 4) The isolation rate of resistant strains of specific serogroups was as follows in order : serogroup B(52.4%), serogroup C(33.3%), serogroup E(25%), serogroup D(9.8%), S. typhi(4.2%), serogroup A(0%). 5) The frequency of animicrobial resistance in Salmonella strains to tested 8 antimicrobial agents was as follows : ampicillin(28.8%), carbenicillin(28.1%), chloramphenicol(16.4%), kanamycin(5.9%), trimethoprim-sulfamethoxazole(5.3%), cephalothin(2.3%), gentamicin(0.9%), amikacin(0.5%). 6) The most of antimicrobial-resistant Salmonella(95.0% of resistant strains) has multiple drug resiatance. 7) The frequency of clinical manifestations of nontyphoid salmonellosis was as follows : enterocolitis(80.1%), bacteremia without focal infection(13.1%), focal infection(6.8%). 8) The clinical variables statistically significant between resistant and sensitive Salmonella infection are frequency of bacteremia and duration of admission.
CONCLUSION
Different serogroups of Salmonella isolates reveal the different frequency & pattern in antimicrobial resistance. The frequency of antimicrobial resistance for Salmonella isolates is markely increased during recent 9 years. In preparation for the future outbreaks of multiresistant sallmonellosis, nationwide studies should be carried out periodically to monitor effectively trends in the antimicrobial resistance of Salmonella and the development of effective and practical alternative therapy for resistant salmonellosis is clearly needed.