Periodontal disease as reservoir for multi-resistant and hydrolytic enterobacterial species

This investigation aimed to isolate enteric rods from subgingival sites of patients presenting chronic periodontitis lesions, and to assess antimicrobial resistance and expression of hydrolytic enzymes. Enterobacteriaceae were isolated from 20% patients, and assayed for antimicrobial susceptibility and hydrolytic enzymes with specificity to different substrates. Isolates comprised seven Enterobacter cloacae (43·75%), five Serratia marcescens (31·25%), one Klebsiella pneumoniae (6·25%), one Enterobacter aerogenes (6·25%), one Pantoea agglomerans (6·25%), and one Citrobacter freundii (6·25%). Gelatinase activity was observed for 75% strains; caseinase and elastase was produced by six and two strains, respectively. DNase, lecithinase and lipase were expressed by S. marcescens. Most of strains were resistant to ampicillin (93·75%) and amoxicillin/clavulanic acid (81·25%). The majority of strains were susceptible to cephalosporins and aztreonam. Enterobacteria remained susceptible to imipenem, streptomycin and fluoroquinolones. Resistance to gentamicin, amikacin, sulfamethoxazole/thrimethoprim, tetracycline, and chloramphenicol were also observed. Eight strains presented multiple drug resistance. Subgingival sites from periodontal diseases contain multi-resistant and hydrolytic enzyme-producing enterobacteria that may contribute to overall tissue destruction and spreading. Enterobacteria isolated from patients generally considered as healthy individuals poses periodontal diseases as reservoir for systemic infections particularly in immunocompromised and hospitalized hosts.