ObjectiveTo phenotypically evaluate biofilm production by Pseudomonas aeruginosa clinically isolated from patients with ventilator-associated pneumonia.MethodsTwenty clinical isolates of P. aeruginosa were analyzed, 19 of which were from clinical samples of tracheal aspirate, and one was from a bronchoalveolar lavage sample. The evaluation of the capacity of P. aeruginosa to produce biofilm was verified using two techniques, one qualitative and the other quantitative.ResultsThe qualitative technique showed that only 15% of the isolates were considered biofilm producers, while the quantitative technique showed that 75% of the isolates were biofilm producers. The biofilm isolates presented the following susceptibility profile: 53.3% were multidrug-resistant, and 46.7% were multidrug-sensitive.ConclusionThe quantitative technique was more effective than the qualitative technique for the detection of biofilm production. For the bacterial population analyzed, biofilm production was independent of the susceptibility profile of the bacteria, demonstrating that the therapeutic failure could be related to biofilm production, as it prevented the destruction of the bacteria present in this structure, causing complications of pneumonia associated with mechanical ventilation, including extrapulmonary infections, and making it difficult to treat the infection.

Staphylococcus aureus is the main human pathogen that colonizes individuals in general population. The objective of the study was evaluate the epidemiological and sensitivity profile of S. aureus lineage, isolated in health care workers (HCW) of a University Hospital in Pernambuco state, Brazil. Biological samples of hands and nasal cavities were sown in agar sheep blood. Colonies under suspicion of being S. aureus were identified using Gram staining, catalase test and coagulase, mannitol-salty agar fermentation and DNAse agar. The resistance to mupirocin was analyzed through the Kirby Bauer technique. In relation to methicillin and vancomycin the determination was by the minimum inhibitory concentration method (E-test). From the 202 HCW evaluated, 52 were colonized by S. aureus (25,7%). The factors associated to the colonization by S. aureus were: age-group, professional category, use of individual protection equipments (frequency and numbers). All S. aureus isolate lineages were sensitive to mupirocin and vancomycin, and three of them were identified as methicillin-resistant. The prevalence of MSSA and MRSA among HCW was considered low and was below the results described in the literature. The isolate S. aureus lineages have shown low resistance profile.

In the Staphylococcus spp. analyzed, the ermC gene was found more often than the ermA, although the iMLSB phenotype had been less frequent than the cMLSB. It was important to perform the D test for its detection to guide therapeutic approaches.

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) strains have been responsible for many nosocomial outbreaks. Within hospitals, colonized employees often act as reservoirs for the spread of this organism. This study collected clinical samples of 91 patients admitted to the intensive care unit (ICU), hemodialysis/nephrology service and surgical clinic, and biological samples from the nasal cavities of 120 professionals working in those environments, of a University Hospital in Recife, in the State of Pernambuco, Brazil. The main objective of this study was to determine the occurrence and dissemination of methicillin-and vancomycin-resistant Staphylococcus spp. Methods: The isolates obtained were tested for susceptibility to oxacillin and vancomycin and detection of the mecA gene. In addition, the isolates were evaluated for the presence of clones by ribotyping-polymerase chain reaction (PCR). Results: MRSA occurrence, as detected by the presence of the mecA gene, was more prevalent among nursing technicians; 48.1% (13/27) and 40.7% (11/27) of the isolates were from health professionals of the surgical clinic. In patients, the most frequent occurrence of mecA-positive isolates was among the samples from catheter tips (33.3%; 3/9), obtained mostly from the hemodialysis/nephrology service. Eight vancomycin-resistant strains were found among the MRSA isolates through vancomycin screening. Based on the amplifi cation patterns, 17 ribotypes were identifi ed, with some distributed between patients and professionals. Conclusions: Despite the great diversity of clones, which makes it diffi cult to trace the source of the infection, knowledge of the molecular and phenotypic profi les of Staphylococcus samples can contribute towards guiding therapeutic approaches in the treatment and control of nosocomial infections.

This study was performed with the objective to identify the prevalence of colonization by Staphylococcus aureus in nursing professionals from a teaching hospital in Pernambuco, and evaluate the resistance profile of these isolates. To do this, we performed a cross-sectional study where biological samples were collected from the hands and nasal cavities of the subjects. S. aureus was identified using agar (blood agar and mannitol salt) via catalase and coagulase tests. The sensitivity profile was determined by Kirby Bauer technique and determination of methicillin resistance was performed with oxacillin screening with sodium chloride (NaCl) addition. Of the 151 professionals evaluated, 39 were colonized which showed a prevalence of 25.8%. Among the variables studied, age and use of PPE were associated with colonization by the organism. Of all the isolates, only five were resistant to methicillin.

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BACKGROUNDStaphylococcus aureus has a notable ability to acquire resistance to antibiotics, and methicillin resistance represents a growing public health problem. Methicillin-resistant S. aureus (MRSA) has also become important outside the hospital environment, particularly in the United States. In Brazil, since 2005, cases of community skin infections caused by MRSA have been reported, but resistance studies involving outpatients are scarce.OBJECTIVETo know the resistance profile of S. aureus involved in skin and soft tissue infections of patients seen at the Dermatology outpatient clinic of a university hospital in Recife, Pernambuco State, northeastern Brazil. METHODSProspective study involving 30 patients with skin and soft tissue infections, seen at the Dermatology outpatient clinic from May until November 2011. To evaluate the susceptibility of S. aureus to antibiotics, the disk diffusion method and oxacillin screening agar were used. RESULTSFrom a total of 30 samples of skin lesions, 19 (63%) had positive culture for S. aureus. The following resistance patterns of S. aureus were observed: penicillin, 95%; tetracycline, 32%; erythromycin, 21%; gentamicin, 16%; cefoxitin, 11%; oxacillin, 11%; trimethoprim-sulfamethoxazole, 11%; chloramphenicol, 11%; clindamycin, 5% ; and ciprofloxacin, 0%. One of the identified MRSA was obtained from a patient without risk factors for its acquisition, and was resistant, beyond to the beta-lactams, only to tetracycline. CONCLUSIONSWith regard to the resistance patterns of S. aureus, resistances to tetracycline, erythromycin and gentamicin were the highest. It was documented, for the first time in Pernambuco, a case of skin infection caused by community-associated MRSA.

Introduction:The increasing reports of vancomycin-resistant Staphylococcus strains (VRS) haves caused concern worldwide, from the laboratory detection to patient management. This study aimed to identify the occurrence of VRS strains among healthcare professionals from a university hospital. Methods: A total of 102 Staphylococcus sp. isolates from healthcare professionals, obtained in a previous study were evaluated according to standard techniques for VRS detection. Results: After screening inoculation of plates containing 6µg/ml of vancomycin, 19 resistant isolates were identified. The susceptibility profile to other antimicrobials revealed 18 multidrug resistant isolates. The minimum inhibitory concentration (MIC) was determined by E-test and broth microdilution. According to E-tests, of 19 isolates grown in BHI-V6, four isolates presented MIC ≥ 128 µg/ml, seven with MIC ranging from 4 to 8 µg/ml, and eight with MIC ≤ 2µg/ml. By broth microdilution, 14 isolates presented MIC ≤ 2 µg/ ml and five with MIC ≥ 16µg/ml. The presence of the gene vanA was determined by PCR in the five resistant isolates, and this gene was detected in one of the strains. Furthermore, among the 19 strains, the gene mecA was found in 13 (39,4%) isolates, including the strain carrying the gene vanA. Conclusions: Based on these results, we highlight the presence of one strain carrying both vanA and the mecA genes, as well as multidrug-resistant strains colonizing healthcare professionals, and their importance as potential vectors to spread strains carrying resistance genes in the hospital environment.