Infections with NontyphoidalSalmonellaSpecies Producing TEM-63 or a Novel TEM Enzyme, TEM-131, in South Africa

Open Access
Publisher Website
Google Scholar
Abstract
Salmonellaspp. producing extended-spectrum beta-lactamases (ESBLs) have been reported in many countries, but there is no information on their prevalence in Africa. ESBL-producingSalmonella entericaserotype Isangi andS. entericaserotype Typhimurium strains have been noted in South Africa since 2001. A total of 160 consecutive isolates ofSalmonellaspp. were collected from 13 hospitals located in different cities in South Africa over a 5-month period from December 2002 to April 2003. All strains were screened for production of ESBLs by the double disk diffusion test and for AmpC production by assessing resistance to cefoxitin.blaSHV,blaTEM,blaCTX-M, andblaCMY-2were sought from all ESBL-positive and cefoxitin-resistant isolates. A total of 15.6% (25 of 160) isolates produced SHV or TEM ESBLs, and 1.9% (3 of 160) produced CMY-2. NineS. entericaserotype Typhimurium, eightS. entericaserotype Isangi, and threeS. entericaserotype Muenchen strains produced either TEM-63 or a derivative of TEM-63 designated TEM-131. Both TEM-63 and TEM-131 have an isoelectric point of 5.6, and their sequences have the following amino acid substitutions compared to the TEM-1 sequence: Leu21Phe, Glu104Lys, Arg164Ser, and Met182Thr. Additionally, TEM-131 has an Ala237Thr substitution. ESBL-producingSalmonellaspp. have become a significant public health problem in South Africa with particular implications for the treatment of serious nontyphoidalSalmonellainfections in children, for whom extended-spectrum cephalosporins were the preferred treatment.

This publication has 49 references indexed in Scilit: