TY - JOUR AU - Taj, Yasmeen AU - Essa, Farhan AU - Aziz, Faisal AU - Kazmi, Shahana Urooj PY - 2011/12/13 Y2 - 2024/03/28 TI - Study on biofilm-forming properties of clinical isolates of Staphylococcus aureus JF - The Journal of Infection in Developing Countries JA - J Infect Dev Ctries VL - 6 IS - 05 SE - Original Articles DO - 10.3855/jidc.1743 UR - https://www.jidc.org/index.php/journal/article/view/22610706 SP - 403-409 AB - <p>Introduction:<strong> </strong>The purpose of this study was to observe the formation of biofilm, an important virulence factor, by isolates of <em>Staphylococcus aureus</em> (<em>S. aureus</em>) in Pakistan by different conventional methods and through electron microscopy.</p> <p>Methodology: We screened 115 strains of <em>S. aureus </em>isolated from different clinical specimens by tube method (TM), air-liquid interface coverslip assay method, Congo red agar (CRA) method, and scanning electron microscopy (SEM).</p> <p>Results: Out of 115 <em>S. aureus</em> isolates, 63 (54.78%) showed biofilm formation by tube method. Biofilm forming bacteria were further categorized as high producers (n = 23, 20%) and moderate producers (n = 40, 34.78%). TM coordinated well with the coverslip assay for strong biofilm-producing strains in 19 (16.5%) isolates. By coverslip method, weak producers were difficult to differentiate from biofilm negative isolates. Screening on CRA showed biofilm formation only in four (3.47%) strains. Scanning electron micrographs showed the biofilm-forming strains of <em>S. aureus</em> arranged in a matrix on the propylene surface and correlated well with the TM.</p> <p>Conclusion: Biofilm production is a marker of virulence for clinically relevant staphylococcal infections. It can be studied by various methods but screening on CRA is not recommended for investigation of biofilm formation in <em>Staphylococcus aureus</em>. Electron micrograph images correlate well with the biofilm production as observed by TM. </p> ER -