BackgroundSpecies identification and antifungal susceptibility tests were carried out on 212 Candida isolates obtained from bloodstream infections, urinary tract infections and dialysis-associated peritonitis, from cases attended at a Brazilian public tertiary hospital from January 1998 to January 2005.FindingsCandida albicans represented 33% of the isolates, Candida parapsilosis 31.1%, Candida tropicalis 17.9%,Candida glabrata 11.8%, and others species 6.2%. In blood culture, C. parapsilosis was the most frequently encountered species (48%). The resistance levels to the antifungal azoles were relatively low for the several species, except for C. tropicalis and C. glabrata. Amphotericin B resistance was observed in 1 isolate of C. parapsilosis.ConclusionsThe species distribution and antifungal susceptibility herein observed presented several epidemiological features common to other tertiary hospitals in Latin American countries. It also exhibited some peculiarity, such as a very high frequency of C. parapsilosis both in bloodstream infections and dialysis-associated peritonitis. C. albicans also occurred in an important number of case infections, in all evaluated clinical sources. C. glabrata presented a high proportion of resistant isolates. The data emphasize the necessity to carry out the correct species identification accompanied by the susceptibility tests in all tertiary hospitals.

Acute pharyngitis/tonsillitis, which is characterized by infl ammation of the posterior pharynx and tonsils, is a common disease. Several viruses and bacteria can cause acute pharyngitis; however, Streptococcus pyogenes (also known as Lancefi eld group A β-hemolytic streptococci) is the only agent that requires an etiologic diagnosis and specifi c treatment. S. pyogenes is of major clinical importance because it can trigger post-infection systemic complications, acute rheumatic fever, and post-streptococcal glomerulonephritis. Symptom onset in streptococcal infection is usually abrupt and includes intense sore throat, fever, chills, malaise, headache, tender enlarged anterior cervical lymph nodes, and pharyngeal or tonsillar exudate. Cough, coryza, conjunctivitis, and diarrhea are uncommon, and their presence suggests a viral cause. A diagnosis of pharyngitis is supported by the patient's history and by the physical examination. Throat culture is the gold standard for diagnosing streptococcus pharyngitis. However, it has been underused in public health services because of its low availability and because of the 1-to 2-day delay in obtaining results. Rapid antigen detection tests have been used to detect S. pyogenes directly from throat swabs within minutes. Clinical scoring systems have been developed to predict the risk of S. pyogenes infection. The most commonly used scoring system is the modifi ed Centor score. Acute S. pyogenes pharyngitis is often a self-limiting disease. Penicillins are the fi rst-choice treatment. For patients with penicillin allergy, cephalosporins can be an acceptable alternative, although primary hypersensitivity to cephalosporins can occur. Another drug option is the macrolides. Future perspectives to prevent streptococcal pharyngitis and post-infection systemic complications include the development of an anti-Streptococcus pyogenes vaccine.

Peritonitis caused by Staphylococcus aureus is a serious complication of peritoneal dialysis (PD), which is associated with poor outcome and high PD failure rates. We reviewed the records of 62 S. aureus peritonitis episodes that occurred between 1996 and 2010 in the dialysis unit of a single university hospital and evaluated the host and bacterial factors influencing peritonitis outcome. Peritonitis incidence was calculated for three subsequent 5-year periods and compared using a Poisson regression model. The production of biofilm, enzymes, and toxins was evaluated. Oxacillin resistance was evaluated based on minimum inhibitory concentration and presence of the mecA gene. Logistic regression was used for the analysis of demographic, clinical, and microbiological factors influencing peritonitis outcome. Resolution and death rates were compared with 117 contemporary coagulase-negative staphylococcus (CoNS) episodes. The incidence of S. aureus peritonitis declined significantly over time from 0.13 in 1996–2000 to 0.04 episodes/patient/year in 2006–2010 (p = 0.03). The oxacillin resistance rate was 11.3%. Toxin and enzyme production was expressive, except for enterotoxin D. Biofilm production was positive in 88.7% of strains. The presence of the mecA gene was associated with a higher frequency of fever and abdominal pain. The logistic regression model showed that diabetes mellitus (p = 0.009) and β-hemolysin production (p = 0.006) were independent predictors of non-resolution of infection. The probability of resolution was higher among patients aged 41 to 60 years than among those >60 years (p = 0.02). A trend to higher death rate was observed for S. aureus episodes (9.7%) compared to CoNS episodes (2.5%), (p = 0.08), whereas resolution rates were similar. Despite the decline in incidence, S. aureus peritonitis remains a serious complication of PD that is associated with a high death rate. The outcome of this infection is negatively influenced by host factors such as age and diabetes mellitus. In addition, β-hemolysin production is predictive of non-resolution of infection, suggesting a pathogenic role of this factor in PD-related S. aureus peritonitis.

The aim of the present study was to investigate the prevalence of Diarrheagenic Escherichia coli (DEC) pathotypes, a leading cause of diarrhea worldwide, among diarrheal and healthy children, up to 5 years of age, living in the city of Botucatu, São Paulo, Brazil. DEC, investigated by PCR detection of virulence factor-encoding genes associated with the distinct pathotypes, was isolated from 18.0% of the patients, and 19.0% of the controls, with enteroaggregative E. coli (EAEC), the most frequent pathotype, being detected in equal proportion between patients and controls (10.0%). Among the enteropathogenic E. coli (EPEC) isolates, only one isolate was able to produce the localized adherence pattern to HeLa cells, being thus the only typical EPEC identified. All the remaining EPEC were classified as atypical (aEPEC), and detected in 8.0% and 8.5% of the patients and controls, respectively. Regarding the serotypes, 26.5% of the analyzed EPEC isolates belonged to classical EPEC-serogroups, and the only two STEC found were serotyped as O26:H11 (patient) and O119:H7 (control). Antimicrobial susceptibility tests revealed that 43.6%, 29.5% and 2.6% of the DEC isolates were resistant to ampicillin, cotrimoxazole and gentamicin, respectively. Our data indicate that EAEC remains prevalent among children living in Botucatu, and revealed atypical EPEC as emerging putative diarrheal agents in this geographical region.

Background and objectives Coagulase-negative Staphylococcus (CNS) is the most frequent cause of peritoneal dialysis (PD)-related peritonitis in many centers. This study aimed to describe clinical and microbiologic characteristics of 115 CNS episodes and to determine factors influencing the outcome.Design, setting, participants, & measurements This study reviewed the records of 115 CNS peritonitis episodes that occurred in 74 patients between 1994 and 2011 at a single university center. Peritonitis incidences were calculated for three consecutive 6-year periods (P1, 1994-1999; P2, 2000-2005; P3, 2006-2011) and annually. The production of biofilms, enzymes, and toxins was evaluated. Oxacillin resistance was evaluated based on its minimum inhibitory concentration and the presence of the mecA gene.Results The overall incidence of CNS peritonitis was 0.15 episodes per patient per year and did not vary over time (0.12, 0.14, and 0.16 for P1, P2, and P3, respectively; P=0.21). The oxacillin resistance rate was 69.6%. Toxin and enzyme production was infrequent and 36.5% of CNS strains presented the gene encoding biofilm production. The presence of icaAD genes associated with biofilm production was predictive of relapses or repeat episodes (odds ratio [OR], 2.82; 95% confidence interval [95% CI], 1.11 to 7.19; P=0.03). Overall, 70 episodes (60.9%) resolved; oxacillin susceptibility (OR, 4.41; 95% CI, 1.48 to 13.17; P=0.01) and vancomycin use as the first treatment (OR, 22.27; 95% CI, 6.16 to 80.53; P,0.001) were the only independent predictors of resolution.Conclusions Oxacillin resistance and vancomycin use as the first treatment strongly influence the resolution rate in CNS peritonitis, which reinforces the validity of the International Society for Peritoneal Dialysis guidelines on monitoring bacterial resistance to define protocols for initial treatment. These results also suggest that the presence of biofilm is a potential cause of repeat peritonitis episodes.

The flora of CLUs was predominantly constituted by gram-negative bacteria, and P aeruginosa was the most prevalent. The bacterial load of infected ulcers was higher as compared with the others, although some ulcers with GGT also presented a high load. The interpretation of microbiologic tests based on the swab techniques and even on semiquantitative analysis requires close clinical correlation.

Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28 mm (penicillin resistant) and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29 mm), 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%), followed by MIC determination (85.5%), but the specificity of the former was low (40.0%). The nitrocefin test was the least sensitive (28.9%). However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%). The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.

The multiplex PCR assay developed here was found to be sensitive, specific, rapid, and showed good agreement with the phenotypic results besides being less expensive. This PCR method could be used in clinical laboratories for rapid identification and initiation of specific and effective treatment, reducing patient mortality and morbidity. Furthermore, this method may reduce misuse of antimicrobial classes that are more expensive and toxic, thus contributing to the selection of antibiotic-resistant Staphylococcus spp.