The Xpert® MTB/RIF diagnostic test for pulmonary and extrapulmonary tuberculosis in immunocompetent and immunocompromised patients: Benefits and experiences over 2 years in different clinical contexts.

Xpert® MTB/RIF has been widely used for tuberculosis (TB) diagnosis in Brazil, since 2014. This prospective observational study aimed to evaluate the performance of Xpert in different contexts during a two-year period: (i) laboratory and clinical/epidemiological diagnosis; (ii) HIV-positive and -negative populations; (iii) type of specimens: pulmonary and extrapulmonary. Overall, 924 specimens from 743 patients were evaluated. The performance of the assays was evaluated considering culture (Lowenstein Jensen or LJ medium) results and composite reference standard (CRS) classification as gold standard. According to CRS evaluation, 219 cases (29.5%) were classified as positive cases, 157 (21.1%) as 'possible TB', and 367 (49.3%) as 'not TB'. Based on culture, Xpert and AFB smear achieved a sensitivity of 96% and 62%, respectively, while based on CRS, the sensitivities of Xpert, AFB smear, and culture were 40.7%, 20%, and 25%, respectively. The pooled sensitivity and specificity of Xpert were 96% and 94%, respectively. Metric evaluations were similar between pulmonary and extrapulmonary samples against culture, whereas compared to CRS, the sensitivities were 44.6% and 29.3% for the pulmonary and extrapulmonary cases, respectively. The Xpert detected 42/69 (60.9%) patients with confirmed TB and negative culture on LJ medium, and 52/69 (75.4%) patients with negative AFB smear results. There was no significant difference in the diagnostic accuracy based on the types of specimens and population (positive- and negative-HIV). Molecular testing detected 13 cases of TB in culture-negative patients with severe immunosuppression. Resistance to rifampicin was detected in seven samples. Herein, Xpert showed improved detection of pulmonary and extrapulmonary TB cases, both among HIV-positive and -negative patients, even in cases with advanced immunosuppression, thereby performing better than multiple other diagnostic parameters.

O diagnóstico sorológico pode detectar a colonização por pseudomonas aeruginosa mais rápido do que as culturas em crianças com fibrose cística? Um estudo de coorte prospectivo / Can serodiagnosis detect Pseudomonas aeruginosa colonisation faster than cultures in children with cystic fibrosis? A prospective follow-up study

A principal causa de óbito em pacientes com fibrose cística é a infecção pulmonar crônica causada por Pseudomonas aeruginosa, tornando a detecção e o tratamento precoces de crucial importância na prevenção do estabelecimento da infecção crônica. O objetivo do presente estudo foi determinar se anticorpos contra o lipopolissacáride de Pseudomonas aeruginosa em crianças poderiam ser detectados antes do isolamento da bactéria em culturas de secreções respiratórias. Quarenta e quatro crianças diagnosticadas com fibrose cística foram acompanhadas por tr?es anos. Foram coletados swabs de faringe posterior para cultura e amostras de sangue para detecção de anticorpos IgG específicos contra um preparado padrão de antígeno polissacarídico de Pseudomonas aeruginosa. A incidência da colonização detectada pelas culturas aumentou diretamente com a idade. Houve uma relação inversa significativa entre as idades médias e a especificidade do IgG. A detecção da bactéria por cultura propendeu a ocorrer antes do aumento de IgG e a sorologia somente foi capaz de discriminar pacientes positivos e negativos antes da cultura em crianças entre 2 e 4 anos de idade. Na prática clínica, as culturas de orofaringe continuam sendo a principal ferramenta para detectar a colonização por Pseudomonas aeruginosa em crianças pequenas.

Characterization of virulence genes cagA and vacA in Helicobacter Pylori and their prevalence in gastrointestinal disorders

Prevalence of H. pylori infection was determined using cultures of gastric biopsy samples of patients attended at the academic hospital of the Federal University of Paraná, Curitiba, Paraná, Brazil. Molecular methods were used to characterize the cagA and vacA genes from bacterial isolates associated with different diseases presented by patients. Out of a total of 81, forty-two gastric biopsy samples tested were positive for H. pylori, with a prevalence of 51.9 percent. No significant difference was found with regard to the gender (p=0.793) and age (p=0.183) of the patients. Genotype s1m1 vacA gene was found in 67 percent of the cases of peptic ulcer investigated (p=1.0), despite the limited number of patients with this disease (n=3). A correlation between the presence of less virulent strains (s2m2) and reflux esophagitis was found in the majority of the cases (45 percent), but without statistical significance. An association between the prevalence of cagA gene, found in 92 percent of isolates, and peptic ulcer was not observed (p=1.0), suggesting that this gene cannot be considered a specific marker of severity in our environment. The results reinforce the importance of conducting regional studies and the need to characterize H. pylori virulence genes associated with different diseases.

Cefepime versus extended spectrum ß-lactamase-producing Enterobacteriaceae.

The objective of this study was to evaluate the susceptibility to cefepime of a large group of ESBL- producing enterobacteria recently isolated in a Brazilian teaching hospital . The study included 280 strains of ESBL-producing enterobacteria, isolated between 2005 and 2008. The presence of the genes blaCTX-M, blaTEM and blaSHV was determined by PCR and confirmed by nucleotide sequencing. Susceptibility testing for cefepime was performed by disc-diffusion, agar dilution method and E-test®. Among the isolates, 34 (12.1%) presented a cefepime inhibition zone > 21 and MIC < 8 mg/L by agar dilution and E-strip methods. The use of cefepime for the treatment of infections caused by ESBL-producing bacteria has been controversial. Some studies of PD/PK show the probability of achieving the required PD parameters for cefepime, when the MICs were < 8 mg/L, whereas others have reported therapeutic failure with the same MIC. Additional data is essential to come to terms about the report and treatment with cefepime in ESBL-producing organisms especially when these microorganisms are isolated from sterile sites and from critically ill patients.

Cefepime versus extended spectrum β-lactamase-producing Enterobacteriaceae

The objective of this study was to evaluate the susceptibility to cefepime of a large group of ESBL- producing enterobacteria recently isolated in a Brazilian teaching hospital . The study included 280 strains of ESBL-producing enterobacteria, isolated between 2005 and 2008. The presence of the genes blaCTX-M, blaTEM and blaSHV was determined by PCR and confirmed by nucleotide sequencing. Susceptibility testing for cefepime was performed by disc-diffusion, agar dilution method and E-test®. Among the isolates, 34 (12.1 percent) presented a cefepime inhibition zone > 21 and MIC < 8 mg/L by agar dilution and E-strip methods. The use of cefepime for the treatment of infections caused by ESBL-producing bacteria has been controversial. Some studies of PD/PK show the probability of achieving the required PD parameters for cefepime, when the MICs were < 8 mg/L, whereas others have reported therapeutic failure with the same MIC. Additional data is essential to come to terms about the report and treatment with cefepime in ESBL-producing organisms especially when these microorganisms are isolated from sterile sites and from critically ill patients.

Characterization of virulence genes cagA and vacA in Helicobacter Pylori and their prevalence in gastrointestinal disorders.

Prevalence of H. pylori infection was determined using cultures of gastric biopsy samples of patients attended at the academic hospital of the Federal University of Paraná, Curitiba, Paraná, Brazil. Molecular methods were used to characterize the cagA and vacA genes from bacterial isolates associated with different diseases presented by patients. Out of a total of 81, forty-two gastric biopsy samples tested were positive for H. pylori, with a prevalence of 51.9%. No significant difference was found with regard to the gender (p=0.793) and age (p=0.183) of the patients. Genotype s1m1 vacA gene was found in 67% of the cases of peptic ulcer investigated (p=1.0), despite the limited number of patients with this disease (n=3). A correlation between the presence of less virulent strains (s2m2) and reflux esophagitis was found in the majority of the cases (45%), but without statistical significance. An association between the prevalence of cagA gene, found in 92% of isolates, and peptic ulcer was not observed (p=1.0), suggesting that this gene cannot be considered a specific marker of severity in our environment. The results reinforce the importance of conducting regional studies and the need to characterize H. pylori virulence genes associated with different diseases.

Anti-Helicobacter pylori activity of plant extracts traditionally used for the treatment of gastrointestinal disorders

The antibacterial activity of plant extracts obtained from Bixa orellana L., Chamomilla recutita L., Ilex paraguariensis A. St.-Hil., Malva sylvestris L., Plantago major L. and Rheum rhaponticum L. has been evaluated against two reference strains and eleven clinical isolates of Helicobacter pylori. All the plant species chosen are used in popular Brazilian cuisine and folk medicine in the treatment of gastrointestinal disorders. Initial screening was made by the disk diffusion test and then minimum inhibitory concentration was determined by the agar dilution method. The results presented in this work demonstrated that among the plant preparations analyzed, B. orellana L., C. recutita L., I. paraguariensis A. St.-Hil. and M. sylvestris L. were capable of inhibiting the in vitro growth of H. pylori.

Anti-Helicobacter pylori activity of plant extracts traditionally used for the treatment of gastrointestinal disorders.

The antibacterial activity of plant extracts obtained from Bixa orellana L., Chamomilla recutita L., Ilex paraguariensis A. St.-Hil., Malva sylvestris L., Plantago major L. and Rheum rhaponticum L. has been evaluated against two reference strains and eleven clinical isolates of Helicobacter pylori. All the plant species chosen are used in popular Brazilian cuisine and folk medicine in the treatment of gastrointestinal disorders. Initial screening was made by the disk diffusion test and then minimum inhibitory concentration was determined by the agar dilution method. The results presented in this work demonstrated that among the plant preparations analyzed, B. orellana L., C. recutita L., I. paraguariensis A. St.-Hil. and M. sylvestris L. were capable of inhibiting the in vitro growth of H. pylori.

Potencial de contaminaçao de cobertores em hospital / Potential contamination of linen in hospitals

Apesar dos inúmeros esforços que têm sido feitos no Brasil, para a prevençao da infecçao hospitalar, muito pouco tem sido feito com relaçao ao potencial de contaminaçao e transmissao de infecçoes a partir de roupas de cama dos pacientes, mais especificamente dos cobertores, tendo estes um alto grau de contaminaçao por germes patogênicos humanos. Na maioria das vezes estes sao apenas dobrados esteticamente, colocados ao pé da cama ou muito bem embalados e guardados no estado em que se encontram, independentemente do quadro infeccioso de quem ocupou o leito. As bactérias associadas com este tipo de infecçao hospitalar sao geralmente nao esporulados e o S. Aureus é um organismo que particularmente merece atençao. Foram coletados materiais de 30 cobertores dos diversos setores do Hospital de Clínicas da UFPR, em placas de Petri com meio de cultura TSA, tendo um contato de 30 segundos com a superfície do cobertor. Estas placas foram submetidas a incubaçao por 36 C durante a noite, contadas as colônias e identificadas as bactérias. Foram considerados positivos os resultados de cultura das placas tendo mais de 01 (um) microorganismo por cm*. Obedecendo a estes padroes obtivemos 100% de positividade nos materiais coletados. Com este resultado os autores concluem que nao há uma rotina padrao com relaçao à lavagem e cuidados gerais com os cobertores no Hospital de Clínicas da UFPR, evidenciando, portanto, uma importante fonte de infecçao hospitalar