The prevalence of TEM and SHV genes among Extended-Spectrum Beta-Lactamase-producing Klebsiella pneumoniae and Escherichia coli

Background: Antimicrobial resistance to cephalosporin, penicillin and aztreonam is mediated by Extended-Spectrum Beta-Lactamases (ESBL) via hydrolysis of antibiotics. The most common bacteria associated with ESBL among the Enterobacteriaceae are Escherichia coli and Klebsiella pneumonia. Pathogenic Escherichia coli is associated with diarrhoea affecting mostly elderly, children under five years and the immunocompromised. There are a number of antibiotic regimens for treatment among them cephalosporins. There is reported increase in microbial resistance to cephalosporin use and the resistance is mediated by either TEM or SHV genes. Objective: To investigate the prevalence of ESBL-producing E. coli and Klebsiella pneumonia from patients presenting with diarrhea in Machakos District Hospital, Kenya. Methods: Bacterial isolates were identified to species level by biochemical methods and tested for sensitivity to twelve different antibiotics including cephalosporins, aminoglycosides and quinolones. Those resistant to cephalosporins with a zone diameter of ≤20 mm were tested phenotypically for Extended Spectrum Beta Lactamase (ESBL) phantom development and confirmed by MicroScan. Resistant strains to cephalosporin were further tested for presence and frequency of TEM and SHV genes. Results: Out of the 200 K. pneumonia and 100 E.coli tested, 18 (6%) were positive for ESBL production phenotypically. These 18 (100 %) isolates demonstrated phantom phenomena phenotypically. Eight (4%) and 2 (1%) of the 200 K. pneumonia isolates had TEM and SHV resistant genes, respectively. There were 5 (5%) TEM and 3 (3%) SHV detected from 100 E. coli isolates. The 18 phenotypically detected and E-test-positive strains (10 Klebsiella spp. and 8 E. coli) were retested with VITEK (GNS-532 card), and 17 of these strains (94.4%) were subsequently found to be ESBL positive. One strain (5.6%) tested ESBL negative by VITEK. The cefotaxime ESBL strip detected the presence of ESBL activity in these 18 phenotypically-positive strains. Discussion: The detection of ESBL-producing E. coli and Klebsiella isolates from Machakos District Hospital was 6%. The findings point out the need for continuous surveillance to determine prevalence of ESBL-producing Enterobacteria strains for better management of diarrheal illness. Key words: Extended spectrum Beta Lactamases; Cephalosporin resistance genes; Enterobacteriacea

Molecular characterization of fluoroquinolone resistance genes in isolates obtained from patients with diarrhea in Machakos District Hospital, Kenya

Background: Diarrhea caused by Enterobacteriaceae such as Shigella species and Escherichia coli (E. coli) is endemic throughout the world, and is one of the most important causes of global childhood mortality and morbidity. There is a range of antibiotics that can be used for treatment among them quinolones. However, there is emerging increase in microbial resistance to quinolones use, with E. coli and Shigellae among the species of bacteria commonly associated with quinolone resistance. Objective: To investigate the prevalence of quinolone resistance genes in Shigellae and E. coli from patients presenting with diarrhea in Machakos District Hospital. Methods: Bacteria isolates were identified to species level by biochemical methods and serology and thereafter tested for 12 different antibiotics including quinolones, cephalosporins and aminoglycosides. Those resistant to quinolones with a zone diameter of ≤20 mm were tested for the presence of quinolone resistance genes using PCR. The gyrA resistance genes were further analyzed by sequencing to determine mutations within the quinolone resistance regions. Results: There were different E. coli pathotypes and Shigellae spp.  They resisted more than four antibiotics: Ciprofloxacin (4%), (Chloramphenical (28%), Cotrimoxazole (78%), Co-amoxilav (70%) Erythromycin (98%) Cefotoxime (18%) and Tetracycline (56%). Mutations responsible for fluoroquinolone resistance in the gyrA, gyrB, parC, and parE genes of E. coli and Shigella spp were: gyrA (17/30, 36%) gyrB (7/30, 23.3%) topoisomerase (parC 3/30, 10%) parE (3/30, 10%). Discussion: There is an increase in fluoroquinolone resistance in Shigellae and E.coli which points to a major challenge in current treatment strategies. In addition, detection of high resistance found to commonly used antibiotics should serve as a warning call for close surveillance and understanding of the epidemiology of the resistance. Key words: Quinolone antibiotics, resistance, Shigella, Escherichia col

Effect of Piped Water Supply on Human Water Contact Patterns in a Schistosoma haematobium-Endemic Area in Coast Province, Kenya

The effect of a piped water supply on human water contact in a Schistosoma haematobium-endemic area in Coast Province, Kenya was studied. After the construction of five community standpipes and one shower unit, there was a 35.1% reduction in the number of people observed using river water, a 44.1% reduction in the frequency of contact with river water, and a 25.4% reduction in the amount of contact. The frequency of river water contact per person also decreased significantly, but the amount of contact per person did not decrease. The total frequency of contact decreased significantly except for washing clothes by the river, washing utensils, and fishing. The frequency per person did not change for most of the activities and significantly increased for washing clothes. The frequency of river water contact in households with high piped water consumption showed a significant decrease compared with those with low piped water consumption. The volume of consumption of piped water was inversely proportional to the distance from the home to the community standpipe. These results indicate that in the study area, the effect of a piped water supply on river water contact behavior was heterologous while the total river water contact decreased significantly, and that the piped water had a beneficial effect on some villagers but very little effect on others

Characterization of Methicillin-Resistant Staphylococcus Aureus from Skin and Soft Tissue Infections in Patients in Nairobi, Kenya

Article JournalSkin and soft tissue infections (SSTIs) are among the most common infectious diseases and a frequent cause of hospital visits. In this study we sought to assess the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and antibiotic susceptibility patterns in SSTIs in patients attending hospitals in Kenya. Methods: Eighty-two S. aureus isolates recovered from SSTIs from both inpatients and outpatients were screened for antibiotic susceptibility, possession of staphylococcal cassette chromosome mec (SCCmec)gene type, and the Panton–Valentine leukocidin (PVL) toxin gene. The prevalence of MRSA was investigated in relation to the type of patient and infection type, as well as the type of health care facility. Results: Of 60 boil cultures, 39 (65%) grew S. aureus, of out of which 34 (87.2%) were MRSA. Of the 60 abscess cultures, 14 (23.3%) grew S. aureus, of which 10 (71.4%) were MRSA. Of 34 cellulitis cultures, 18 (52.9%) grew S. aureus, of which 16 (88.8%) were MRSA. Of 25 ulcer cultures, 11 (44%) grew S. aureus, of which nine (81.8%) were MRSA. Sixty-nine of 82 S. aureus (84.1%) were MRSA, with 52 (75.4%) possessing SCCmec II type and 14 (20.3%) being positive for the PVL gene. Based on hospitals, it was noted that most MRSA were isolated at publicly funded health care facilities serving an economically disadvantaged segment of Nairobi’s population, such as those living in urban informal settlements. All 82 S. aureus were susceptible to vancomycin and resistant in high numbers to macrolides, aminoglycosides, and quinolones. Bacterial isolates were mostly susceptible to vancomycin, ciprofloxacin and co-trimoxazole, and none was resistant to vancomycin. However, most organisms showed decreased susceptibility to erythromycin and clindamycin. Conclusions: These findings suggest that SCCmec II MRSA and a PVL strain of MRSA are significant pathogens in patients with SSTIs presenting to hospitals in Kenya, and that MRSA cases are prevalent at publicly funded health care facilities