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Background: Biofilm formation by pathogens is of great clinical importance as it mediates persistence and resistance to antibiotics, hence posing difficulty in treatment and management of diseases. The aim of this study was to evaluate the biofilm forming potential of Staphylococcus aureus isolated from urine samples of females with urinary tract infection and to detect the presence of clumping factor (clfA) and intracellular adhesion (icaA) encoding genes.Methodology: A total of 50 S. aureus were obtained from urine samples of women in five hospitals in Lagos State, Nigeria. Isolates were confirmed by standard biochemical and novobiocin susceptibility tests. The isolates were screened for biofilm formation using three methods; Congo-red agar (CRA), tube, and tissue culture plate (TCP) methods. Detection of clfA and icaA genes was done by PCR.Results: The Congo red agar method showed that 39 (78%) of the isolates were biofilm producers while 11 (22%) were non-biofilm producers. However, the tube method indicated that 12 (24%) were strong biofilm producers, 26 (52%) were moderate biofilm producers, and 12 (24%) were non-biofilm producers. The standard TCP assay showed that strong biofilm producers (OD > 0.240) were 13 (26%), moderate biofilm producers were 22 (44%), and weak or non-biofilm producers (OD < 0.120) were 15 (30%). The tube method showed a good correlation with the TCP method for strong biofilm production. Ten (20%) isolates possessed clfA gene and 31 (62%)possessed icaA gene.Conclusion: The ability of S. aureus to form biofilm is a key risk factor that can increase morbidity and mortality from infections they cause. Hence, rapid and sensitive phenotypic methods can be used in screening for biofilm formation thereby providing data that can guide therapy and control of the pathogen. Keywords: Staphylococcus aureus, Biofilm, Clumping factor, Intracellular adhesion

ObjectiveStaphylococcus saprophyticus is a Gram-positive bacterium implicated in urinary tract infections in sexually active women along with other bacteria. There is a special need to accurately isolate and identify this organism in clinical specimens in order to prevent misidentification in the laboratory. The present study was carried out to evaluate the genetic diversity of one hundred different Staphylococcus saprophyticus strains isolated from women presenting with urinary tract infections reporting in four government hospitals in Lagos Metropolis using 16SrRNA gene sequence analysis. ResultsThe PCR-amplified and sequenced 16SrRNA gene of 100 isolates and confirmed 88 strains of S. saprophyticus to subspecies level, while 8 belong to other genera and 4 could not be ascertained due to low significant similarity. Phylogenetic analysis showed the interrelationship between the isolates from different hospitals. The results showed the distribution of the isolates into two broad clusters and twenty-two sub-clusters. The results revealed the genetic diversity of Staphylococcus saprophyticus isolated from women with urinary tract infections in Lagos Metropolis using 16SrRNA gene sequence.