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Introduction: Pseudomonas aeruginosa is one of the main pathogens causing infection in intensive care units (ICUs) and usually presents antimicrobial resistance. Methods: Data were obtained from ICUs between 2010 and 2013. Results: P. aeruginosa had a prevalence of 14.5% of which 48.7% were multidrug resistant. We observed increasing resistance to carbapenems and polymyxin B and growing consumption of aminoglycosides, meropenem, ceftazidime, and polymyxin B. The regression impact between resistance and consumption was significant with respect to amikacin, imipenem, meropenem, and polymyxin B. Conclusions: Monitoring antimicrobial consumption and resistant microorganisms should be reinforced to combat antimicrobial-and multidrug resistance.

We report for the first time in Brazil, a patient from whom an Enterococcus faecalis VanA phenotype was isolated. Glycopeptide resistance is not commonly observed in Enterococcus faecalis, so this finding is of great concern since this species is responsible for 90% of enterococcal infections in Brazil. The isolate was recovered from a surveillance rectal swab culture from a patient with acute lymphocytic leukemia (ALL). Identification to the species level was performed by conventional biochemical tests and Vitek GPI cards. Antimicrobial susceptibility testing was evaluated by use of broth microdilution and Etest (AB BIODISK, Solna, Sweden) methods. The isolate was identified as E. faecalis and was considered resistant to both vancomycin (MIC, > 256 microg/mL) and teicoplanin (MIC, 256 microg/mL). The isolate also showed high level resistance to gentamicin and streptomycin (MICs, > 1024 microg/mL), but was considered susceptible to ampicillin (MIC, 4 microg/mL). Although the frequency of enterococcal infections is very low in most Latin America countries, the finding of glycopeptide (VanA) resistance in E. faecalis increases concern about apreading antimicrobial resistance in this region.

Nosocomial candidiasis is a major concern in tertiary care hospitals worldwide. This infection generally occurs in patients with degenerative and neoplastic diseases and is considered the fourth most frequent cause of bloodstream infections. Diagnosis of candidemia or hematogenous candidiasis has been problematic because clinical signs and symptoms are nonspecific, leading to delays in diagnosis and, consequently, delays in appropriate antifungal therapy. We developed an inhibition enzyme-linked immunosorbent assay (ELISA) for detection of a 65-kDa antigen in an experimental model of candidemia and for diagnosis of patients in intensive care units (ICUs) with suspected candidemia. An anti-65-kDa monoclonal antibody was tested for detection of the 65-kDa antigen produced by Candida albicans, Candida tropicalis, and Candida parapsilosis in murine candidemia models. The 65-kDa antigen was detected in sera at concentrations ranging from 0.012 to 3.25 g/ml. A total of 20 human patients with candidemia were then evaluated with the inhibition ELISA using sequential sera. Sixteen (80%) patients had the 65-kDa antigen in concentrations ranging from 0.07 to 5.0 g/ml. Sequential sera from patients with candidemia presented three different patterns of antigenemia of the 65-kDa molecule: (i) total clearance of antigenemia, (ii) initial clearance and relapse of antigenemia, and (iii) partial clearance of antigenemia. Our results indicate detection of the 65-kDa protein may be a valuable tool for the diagnosis of candidemia by C. albicans, C. tropicalis, and C. parapsilosis.

Tuberculous meningitis (TBM) is a severe form of extrapulmonary tuberculosis. The aims of this study were to evaluate in-house molecular diagnostic protocols of DNA extraction directly from CSF samples and the targets amplified by qPCR as an accurate and fast diagnosis of TBM. One hundred CSF samples from 68 patients suspected of TBM were studied. Four DNA extraction techniques (phenol-chloroform-thiocyanate guanidine, silica thiocyanate guanidine, resin, and resin with ethanol) were compared and CSF samples were used to determine the best target (IS6110, MPB64, and hsp65 KDa) by qPCR. The extraction protocol using the phenol-chloroform-thiocyanate guanidine showed the best results in terms of quantification and sensitivity of PCR amplification, presenting up to 10 times more DNA than the second best protocol, the silica guanidine thiocyanate. The target that showed the best result for TBM diagnosis was the IS6110. This target showed 91% sensitivity and 97% specificity when we analyzed the results by sample and showed 100% sensitivity and 98% specificity when we analyzed the results by patient. The DNA extraction with phenol-chloroform-thiocyanate guanidine followed by IS6110 target amplification has been shown to be suitable for diagnosis of TBM in our clinical setting.