The Prevalence of Extended Spectrum Beta Lactamase Producing Citrrobacter Freundii and Pprovidencia Stuartii from Medical Laboratories in Parts of Lagos State, Nigeria

Abstract

Citrobacter freundii and Providencia stuartii are members of the family Enterobacteriaceae which are emerging as important Extended Spectrum Beta Lactamase (ESBL) producing pathogens. This study was aimed to determine the prevalence of ESBL and carbapenemase production in C. freundii and P. stuartii. from laboratories in the northwest of Lagos. A total of 134 isolates were obtained from laboratories. Isolate identification, antibiotics susceptibility testing, and phenotypic detection of ESBL production were done using standardized procedures. Multiplex polymerase chain reaction (PCR) was performed on ESBL producing isolates to detect blaTEM, blaSHV, blaCTX-M, blaKPC, blaVIM, blaIMP and blaOXA. Out of 134 isolates 15 (11.2%) were Citrobacter freundii and only 2 (1.5%) were of the Providencia genus both of which were Providencia rettgeri and Providencia stuartii. A total of 9 (60%) tested positive for the production of Extended Spectrum Beta Lactamase (ESBL) enzyme while only Providencia stuartii of the Providencia genus also produced ESBL. Also, 8 (47%) of the initial Citrobacter and Providencia isolates produced carbapenemase Molecular characterization showed that 4 (44.4%) and 1 (100%) of the Citrobacter freundii and Providencia stuartii isolates respectively, displayed the presence of CTX-M gene while 2 (20%) of all ESBL producing isolates also possessed SHV gene including 1 (11.1%) of ESBL producing Citrobacter freundii and 1 (100%) of ESBL producing Providencia stuartii. Antibiotic susceptibility testing showed that Citrobacter freundii displayed the highest resistance to Ceftazidime and Cefotaxime at 71.4% and the least resistance to Amoxicillin-Clavulanate at 28.6%. Providencia stuartii also displayed absolute resistance (100%), to cefotaxime and ciprofloxacin and absolute susceptibility (100%) to Ceftazidime. Also, Citrobacter freundii showed the same resistance patterns with 57.1% resistance to Gentamicin, Cefuroxime and Ceftriaxone antibiotics while Providencia stuartii showed varied resistance patterns with absolute resistance (100%), absolute susceptibility (100%) and absolute resistance (100%) to Gentamicin, Cefuroxime and Ceftriaxone antibiotics respectively. In conclusion, the Multiple Antibiotic Resistance Index values of both bacterial genera showed that 70.6% were from High-Risk sources indicating that the majority of bacteria analysed were from environments where they have been subjected to a high burden of antibiotic exposure.