Abstract:
Severely malnourished children have increased risk of severe infections and are therefore more likely to use antimicrobial agents. This could in turn present a strong selection pressure for the emergence and spread of multidrug resistant (MDR) strains.
In this case-control, hospital-based study, 109 E. coli isolates were obtained from both severely malnourished and non-malnourished children. Higher resistances were observed in severely malnourished children to cefpodoxime, cefepime, ceftazidime, cefotaxime, amoxicilin/clavulanic acid, ciprofloxacin, nalidixic acid, chloramphenicol, and gentamicin than in non-malnourished children. Severely malnourished children were 8.2 times more likely to carry ESBL-producers than non-malnourished children (P < 0.0001, O.R - 8.2254, C.I - 3.6374 to 18.6003). blaCTX-M was present in 25 (49%) and 6 (75%) among Cases and Controls respectively. Among the 31 CTX-M producers, 30 (97%) carried blaCTX-M-15. Also blaCTX-M-15 occurred in combination with blaTEM-1 and blaOXA-1 in 10 (32 %) isolates. Other bla alleles detected alongside blaCTX-M-15 but rarely reported globally were blaTEM-33 1(3%) and blaTEM-158 1(3%).
ST131 clones were present in 12 (39%) of the CTX-M-15 isolates. This study also identified a novel ST4481 clone and has been deposited in the Warwick database.
This study reports the first occurrence of CTX-M-15-producing E. coli strains from Mbagathi District Hospital belonging to ST131, ST405, ST44, ST205, ST1642, ST1722, ST617, ST38, ST1675, ST648 and ST167, ST940 and a newly submitted ST4481. ST4481 has not been associated with CTX-M-15 enzymes anywhere else in the world.
This study provides proof that ST131 strains with CTX-M-15 enzymes are indeed widespread. Isolates from non-malnourished children only fit into few ST-clones (ST405, ST940 and ST131) while ambiguity was observed in ST clones from malnourished children.