Clinico- Bacteriological Study Of Adult Periodontitis With Special Reference To Detection Of Beta-Lactamase Producing Anaerobic Bacteria

Abstract

Background and objective: Periodontitis affects significant percentage of population. It is a major public health problem in India with a prevalence of 60-80%. Objectives of this study are to isolate and identify the predominant aerobic and anaerobic microflora, semiquantitative study of isolated microflora in pre-treatment and post-treatment groups, to test the aerobic and anaerobic isolates for the production of enzyme beta- lactamase in pre-treatment group and to study the antibiotic sensitivity pattern of aerobic isolates in pre-treatment group. Material and methods: The present study was conducted in the Department of Microbiology, JNMC, Belgaum. Material was collected from the subgingival pockets in patients with adult generalised chronic periodontitis attending the Periodontology, Outpatient Department at KLE’s V. K. Institute of Dental Sciences, Belgaum over a period of one year from Jan 2010 to Dec 2010. The study comprised of 60 cases of clinically diagnosed new cases of adult chronic generalized periodontitis. Clinical samples were transported to the laboratory in fluid thioglycolate medium. Initially gram’s stain and Fontana stains were done. Aerobic, anaerobic and microaerophilic culture were put up. For aerobic, 5% sheep blood agar, Macconkey agar and for anaerobic, blood agar with haemin and vitamin K, Kanamycin, Vancomycin laked blood agar (KVLB) and Bacteroides Bile Esculin agar (BBE) were used. The media were placed in McIntosh Fildes jar with Internal Gas Generating System and incubated at 37ºC for minimum of 3-5days. Anaerobic growth was identified using standard techniques. Antibiotic sensitivity testing of aerobic organisms were carried out by the Kirby Bauer’s disk diffusion technique. For microaerophilic, brain heart infusion agar and blood agar were placed in 5% CO 2 jar. Beta lactamase production was tested by Double disc diffusion test , Potentiated disc diffusion test and Nitrocefin disc method. Results: Sixty samples yielded 121 isolates of which 78.34% were polymicrobial, 11.66% were monomicrobial and oral commensals were grown in 10% cases. Out of 121 isolates 91.74% were anaerobic, 7.43% were aerobic and 0.83% were microaerophilic. Fusobacterium spp was the most common isolate among anaerobes. Out of 121 isolates 13.22% showed ESBL production and all of them were anaerobic GNB. None of the aerobic isolates were ESBL producers. Semiquantitative study was significant with P value of 0.001. Conclusion: This study has shown that anaerobic bacteria are important cause of chronic periodontitis, along with aerobes and microaerophilic organisms. Isolation of these anaerobic organisms and their antibiotic susceptibility should be determined to start appropriate antibiotic therapy as early as possible to overcome the morbidity and mortality associated with this disease and to prevent the development of resistant strains.