Plasmid Profile Analysis of Multi-drug Resistant Proteus spp isolated from Patients with Wound Infection in Northeastern Nigeria

Aims: We analysed the prevalence of plasmid mediated multidrug resistance among Proteus spp isolated from wound infection patients attending healthcare centers in Maiduguri.

Methodology: 320 wound swab samples were collected from August 2016 to June 2017, and investigated via microscopy, cultured on Blood agar and MacConkey agar. Suspected Proteus spp isolates were further confirmed using biochemical tests. Kirby bauer disc diffusion test was used to determine the antimicrobial susceptibility pattern. Isolates confirmed to be multidrug resistant (MDR) were subjected to gel electrophoresis for the determination of plasmid profile.

Results: Twenty eight (28) samples yielded Proteus spp, giving a prevalence rate of 8.75%. Proteus mirabilis was the most significant specie isolated (32.14%). Isolates were most sensitive/least resistant to Ciprofloxacin (85.71%/14.29%) and most resistant/least sensitive to Augmentin (10.71%/89.29%). 64.28% of isolates observed were MDR strains and were quite significant among patients between the ages of 21-30years (21.43%). MDR Proteus mirabilis was most the significant and highly prevalent among patients suffering from wound sepsis and burns (10.71% respectively). The association between MDR Proteus spp and wound types was statistically not significant (X2 =7.342, p>0.01). Plasmid profile analysis revealed that 72.22% of the MDR isolates harbour plasmids with a DNA fragment size of 100 bp and a molecular weight of 31ng/10µl. An average of 7.22% of MDR isolates were cured of their plasmids while an average of 56.67% of MDR isolates resisted curing.

Conclusion: Here, we report a high prevalence of multidrug resistance and a high rate of plasmid carrying strains of Proteus spp in wounds of hospitalised patients. We suggest that there is a role played by plasmid in the mediation of multidrug resistance among the MDR Proteus spp isolated, where the majority of the MDR isolates observed carry plasmids.