No abstract

Analysis of the clinical significance of CoNS isolated from hemocultures and the precise detection of oxacillin resistance represent decisive factors for the correct choice of antibiotic therapy. Although vancomycin constitutes the normal treatment in most Brazilian hospitals, reduction in its use is recommended.

Platelet Concentrates (PCs) are the blood components with the highest rate of bacterial contamination, and coagulase-negative staphylococci (CoNS) are the most frequently isolated contaminants. This study investigated the biofilm formation of 16 contaminated units out of 691 PCs tested by phenotypic and genotypic methods. Adhesion in Borosilicate Tube (ABT) and Congo Red Agar (CRA) tests were used to assess the presence of biofilm. The presence of icaADC genes was assessed by means of the Polymerase Chain Reaction (PCR) technique. With Vitek(r)2, Staphylococcus haemolyticus was considered the most prevalent CoNS (31.25%). The CRA characterized 43.8% as probable biofilm producers, and for the ABT test, 37.5%. The icaADC genes were identified in seven samples by the PCR. The ABT technique showed 85.7% sensitivity and 100% specificity when compared to the reference method (PCR), and presented strong agreement (k = 0.8). This study shows that species identified as PCs contaminants are considered inhabitants of the normal skin flora and they might become important pathogens. The results also lead to the recommendation of ABT use in laboratory routine for detecting biofilm in CoNS contaminants of PCs.

The objective ofthis study was to characterize the prevalence and susceptibility profile ofStaphylococcus aureus isolates at University Hospital ofSanta Maria, through data collection at the Laboratory ofClinical Analysis, during April to June 2009. Were requested 3270 cultures and 1123 (34%) were positive. The prevalence of S. aureus in relation to positive cultures was 89 (7,93%). It was found that these strains, 33% were resistant to oxacillin and 34.45% showed resistance related erm gene. High sensitivity to trimethoprim-sulfamethoxazole (72/80%) was detected for the automation and no strain showed resistance to vancomycin. Therefore, the prevalence of S. aureus and oxacillin resistance at HUSM were lower than observed in other tertiary hospitals in Brazil.

The Streptococcus agalactiae colonization prevalence and its susceptibility to antimicrobials in pregnant women at University Hospital of Santa Maria (HUSM) were evaluated from June to December 2009. The vaginal-rectal material was inoculated into tubes containing Todd-Hewitt broth with subsequent subculture on blood agar. The GBS identification was made through presumptive tests, confirmed by serological test and its susceptibility was evaluated. The occurrence ofGBS maternal-fetal transmission in the colonized pregnant women was researched. The GBS colonization was 11.11%. All strains were susceptible to penicillin, ampicillin, and vancomycin. Two strains (50%) were intermediate to clindamycin and one (25%) intermediate to erythromycin. A newborn whose mother was colonized had early-onset neonatal infection by GBS. By this, it is very important the research about the colonization by GBS in all pregnant women from 35 to 37 weeks of gestation and the use of intrapartum antibiotic prophylaxis for colonized pregnant women.Descriptors: Streptococcus agalactiae; Prevalence; Pregnant women; Newborns; Microbial Sensitivity Tests. RESUMOAvaliou-se a prevalência de colonização pelo Streptococcus agalactiae e o seu perfil de sensibilidade frente aos antimicrobianos em gestantes no Hospital Universitário de Santa Maria (HUSM), de junho a dezembro de 2009. O material vaginal-retal foi inoculado em tubos contendo caldo Todd-Hewitt com posterior subcultura em ágar sangue. A identificação do EGB foi realizada através de testes presuntivos, confirmadas por teste sorológico e avaliado seu perfil de sensibilidade. Pesquisou-se ocorrência de transmissão materno-fetal do EGB nas gestantes colonizadas. A prevalência de colonização foi de 11,11%. Todas as cepas foram sensíveis à penicilina, ampicilina e vancomicina. Duas cepas (50%) foram intermediárias à clindamicina e uma (25%) intermediária à eritromicina. Um recém-nascido de mãe colonizada teve infecção neonatal de início precoce por EGB. Confirma-se a importância da pesquisa de colonização por EGB em todas as gestantes entre 35ª e 37ª semana de gestação e uso de quimioprofilaxia intraparto nas gestantes colonizadas.