Pathogenic Alteration On Burned Wounds And Different Kinds Of Samples Of Burn Patients

Objective: The present study aims at the trend of time related changes with local bacterial alteration of bacterial resistance in burns and the relationship between different kinds of samples of burn patients in our burn center during a 10-year period. Methods: Retrospective analysis of microbiological results of swab samples,sputum samples,catheters samples,blood samples and susceptibility of antibiotics on burned wounds between October 2001 and October 2010 was carried out. Results: A study of 7153 microbial isolates was performed. Of these isolates,G+ 4423 (59.9%), G- 2730 (38.2%), fungi 137 (1.9%). For burn patients in ICU, 3620 swab samples isolates was performed, Of these isolates,G+ 4423 (56.2%), G- 2730 (40.0%), fungi 137 (3.8%). Staphylococcus aures was the most commonly isolated pathogen (38.2%) followed by Acinetobacter baumannii (16.2%), Streptococcus viridans (11.4%). The species ratios of Staphylococcus aureus and Acinetobacter baumannii increased significantly from 1st to 8th week of hospitalization, while those of Streptococcus viridans, Pseudomonas aeruginosa and coagulase-negative staphylococci decreased during the same period. For burn patients in General wards, 3533 swab samples isolates was performed, Of these isolates,G+ 1823 (51.6%), G- 1710 (48.4%). Streptococcus viridans was the most commonly isolated pathogen (28.3%) followed by Staphylococcus aures (20.0%), Acinetobacter baumannii (15.5%). The species ratios of Staphylococcus aureus and Pseudomonas aeruginosa increased significantly from 1st to 6th week of hospitalization, while those of Streptococcus viridans, and Acinetobacter baumannii decreased during the same period. Bacterial resistance rates were compared between the periods 2001-2005 and 2006-2010. The antimicrobial resistance of the commonly isolated pathogens in our study had increased in the past 10 years. Vancomycin remained as the most sensitive antibiotic in Staphylococcus aureus including methicillin-resistant Staphylococcus aureus (MRSA). The most commonly used antibiotics for Streptococcus viridans were semi-synthetic products of the penicillin. Pseudomonas aeruginosa and Acinetobacter baumannii were less resistance to cefoperazone and amikacin. The rates of the same strain in swab and sputum samples, swab and catheter samples, catheter and blood samples were 78.4%, 62.8% and 87.5% respectively. Conclusion: The domain pathogen in our burn Center was G+ for the past ten years. It was very likely that the majority of infections caused by Streptococcus viridans, Pseudomonas aeruginosa and coagulase-negative staphylococci occurred in the early stage of burn course and the majority of infections caused by Acinetobacter baumannii and Staphylococcus aures occurred 6 weeks after admission for patients in ICU. While the majority of infections caused by Streptococcus viridans and Acinetobacter baumannii occurred in the early stage of burn course and the majority of infections caused by Pseudomonas aeruginosa and Staphylococcus aures occurred 4 weeks after admission for patients in ICU. There was high correlation betweens between swab and sputum samples, swab and catheter samples, catheter and blood samples.