Clinicomicrobiological study of bacteraemia caused by coliforms in adults

Introduction: Bacteraemia due to gram-negative bacilli is a huge challenge to the clinicians because of the rapidly emerging multidrug resistance among these microorganisms. Aim: To study the associated infections and risk factors, antibiotic resistance in coliforms by phenotypic and genotypic methods, to evaluate antibiotic treatment and outcome in coliform bacteraemia. Materials and Methods: The study was carried out in the Microbiology laboratory of a tertiary care centre. Blood samples were cultured using BacT/ALERT. Antibiotic susceptibility pattern was noted by Vitek 2 Compact system. Phenotypic tests were performed for Amp C beta lactamase, Carbapenemase and MBL.blaNDM-1 & blaKPC gene in carbapenem resistant strains of Coliforms were detected by conventional PCR. The statistical methods used were Chi-square test and Odds ratio. Results: Urinary Tract Infection (UTI), skin and soft tissue infections and pneumonia were associated with bacteraemia. Risk factors were invasive procedures, previous hospital and ICU admission. Penicillins, Fluoroquinolones, 3rd generation cephalosporins showed high resistance. Of the 25 Carbapenem resistant isolates, Modified Hodge Test (MHT) positive were 11. MBL production by E-test detected 14 of the 25. Of 68 isolates resistant to 3rd generation Cephalosporins, 35 were Amp C producers. Sixteen isolates harbored blaNDM-1, none had blaKPC. Mortality rate was 11.4%. Conclusion: ESBLs and Carbapenem resistant strains are spreading fast in community and pose therapeutic challenges. There is a dire need to initiate regional surveillance, carry out more effectual antibiotic stewardship and infection control measures to prevent further spread.