A Study of Changing Pattern of Bacterial Flora and Antimicrobial Resistance in Patients with Major Burns

Infection is one of the most common causes of mortality and morbidity in burn patients. The clinical diagnosis of bacteraemia and/or sepsis is difficult for a number of reasons. It could be symptomatic and/or may be asymptomatic as a result of immune deficiency secondary to thermal injury, malnutrition, anaemia, and damage to immunological barriers. The aim of this study was to evaluate the changing Pattern of bacterial flora and antimicrobial resistance in patients with major burns.

A cross sectional study was conducted at J. N. Medical College Hospital, AMU, Aligarh, from January to June 2010. Sensitivity/susceptibility Pattern of the isolates was determined by disc diffusion method.

A total of 100 patients were enrolled in the study. Staphylococcus was the most common gram positive bacteria isolated from burn wounds. Similarly, Pseudomonas aeruginosa was the most common gram negative bacteria isolated from burn wounds. Staphylococcus aureus was found to be most resistant to Cotrimoxazole (55.6%), followed by Ampicillin (52.4%) and Ofloxacin (46.0%), and least resistant to Oxacillin (3.1%-Methicillin resistant Staphylococcus aureus) and Vancomycin (none). Pseudomonas aeruginosa was found to be most resistant to Ciprofloxacin (65.7%), followed by Ofloxacin (59.7%) and Gatifloxacin (55.2%), and least resistant to Imipenem (none) followed by Piperacillin (17.9%), Cefoperazone + Sulbactum (37.3%) and Amikacin (41.8%).

In burn wounds, Gram-positive organisms are initially prevalent, then gradually become superseded by Gram-negative opportunists that appear to have greater propensity to invade. In light of our findings, regular antibiotic resistance test has to be done for each patient in order to select an appropriate antimicrobial agent.