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Background: The Xpert Mycobacterium tuberculosis Rifampicin (MTB-RIF) is a technological innovation that presents precision and speed in the diagnosis of tuberculosis (TB). The study aimed to evaluate the performance of Xpert MTB/RIF in the TB diagnosis and compare its results with those of culture, species identification, Antimicrobial Susceptibility Testing (AST), and rpoB gene sequencing of discordant results in AST, used for the diagnosis of TB in a reference laboratory., Methods: Cross-sectional descriptive study of pulmonary and extrapulmonary samples requesting Xpert MTB/RIF and culture for TB diagnosis from 2015 to 2019 at Adolfo Lutz Institute-São Paulo/Brazil. The analysis was performed with Epi-Info 7.2.1, presenting the distribution of frequencies and, for comparative analyses, Pearson's Chi-square test and Fisher's exact test were used, considering P ≤ 0.05 as statistically significant. For variables agreement, the Kappa method was used., Results: A total of 1575 pulmonary and extrapulmonary samples were analyzed using Xpert MTB/RIF and culture, of which 293 were positive for the MTB Complex in both methodologies with a sensitivity of 94.55%; specificity of 95.97%; accuracy 95.69%; positive predictive value 85.53%; negative predictive value 98.59%, substantial agreement by Kappa 0.87, and detection sensitivity even at lower levels of bacillary load (P < 0.05). The Xpert MTB/RIF and AST showed concordant results (P < 0.05)., Conclusion: The study brings forward that the Xpert MTB/RIF shows substantial agreement with the results of culture and AST, contributing to the diagnosis of TB and the rapid detection of resistance. The sequencing of resistant cultures in Xpert MTB/RIF and sensitivity in AST identified the H526N mutation, characterized by a low level of resistance to RIF., Competing Interests: None

Background: The diagnosis of leprosy is based on the characteristic signs and symptoms of the disease, subsidized by laboratory tests. When positive, the bacilloscopy closes the diagnosis for leprosy. Phenolic glycolipid-I, or PGL-I, is a molecule in the bacillus cell wall that confers a greater immune response. The ML Flow test is an immunochromatographic test for the detection of anti-PGL-I IgM in human blood or serum., Methods: A prospective study with data collection and biological materials in patients with suspected leprosy from August 2020 to May 2021. For microscopy, intradermal smears were stained with Auramine O, and after reading under a fluorescence microscope, reviewed by Ziehl-Neelsen. The ML flow test was performed according to the Bührer-Sékula protocol. To assess the agreement between the methods, the Kappa index was estimated., Results: Of the 94 suspected leprosy patients, 31 (32.9%) were diagnosed with leprosy. There was moderate agreement between the results of the ML Flow and Auramine O tests (Kappa = 0.58) and substantial agreement between the ML Flow and Ziehl-Neelsen microscopy (Kappa = 0.72). In paucibacillary cases, serology was positive in 100% of patients., Conclusions: This study concluded that the Ziehl-Neelsen technique remains the best option for standard leprosy staining, and the ML flow test is more positive among the three techniques evaluated and can be an effective tool in the early diagnosis of leprosy cases., Competing Interests: None

Background: Rapidly growing mycobacteria (RGM) are a group of nontuberculous mycobacteria (NTM) implicated in difficult-to-treat pulmonary and extrapulmonary diseases, possibly associated with invasive procedures and failures in sterilization of materials and equipment., Methods: We report our experience with the laboratory identification of RGM in a routine work and give an overview of the RGM isolated in our setting. Laboratorial data from all RGM mycobacterial isolates received at Adolfo Lutz Institute of São José do Rio Preto were analyzed from January 2000 to December 2015., Results: Five hundred and seventy-nine isolates were identified with NTM, of which 193 were RGM, which affected 113 patients. Among the 113 patients, the female gender was more frequent (55%) and the average age was 50 years. Pulmonary samples were the most frequent (79%), and 54.9% of the cases were isolated from sputum. Twelve different species were found and the most identified were group Mycobacterium abscessus and Mycobacterium fortuitum, making up 77.9% of all identified RGM. The most frequent comorbidities were smoking (n = 21), alcoholism (n = 12), and human immunodeficiency virus (n = 16). Drug susceptibility test was performed for nine patients and all showed susceptibility to amikacin and seven resistances to doxycycline., Conclusions: This study showed the experience of mycobacterial diagnosis in a routine laboratory, revealing that failure to meet the bacteriological criteria generates losses in the establishment of cases of RGM and consequently its correct treatment., Competing Interests: None

Unlabelled: Leprosy, a chronic infectious disease caused by Mycobacterium leprae, can damage the peripheral nervous system and represents one of the leading causes of nontraumatic neuropathy in some developing countries. The NINJURIN1 is a cell adhesion molecule that provides suitable substrates for repair of Schwann cells after peripheral nerve injury. The single nucleotide polymorphism NINJ1, is the result of a transversion of an adenine to a nucleotide polymorphic cytokine (A→C), responsible for an amino acid exchange of asparagine to alanine at position 110 of the protein (asp110ala)., Objectives: The aim of this study was to investigate the importance of the polymorphism in the NINJ1 gene for neural impairment during leprosy course., Methods: A single nucleotide polymorphism (asp110ala) was searched in 218 leprosy patients and 244 non-leprosy subjects using a polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) method., Results: No statistical differences were observed in the frequency of the asp110ala SNP between leprosy patients versus non-leprosy and multibacillary versus paucibacillary clinical forms. The C allele (ala110) is increased among patients exhibiting nerve impairment (p=0.0379). Also, leprosy patients with the CC genotype (ala/ala) had a higher risk (OR=4.21) of developing nerve disability when compared those carrying the AA genotype (asp/asp) (OR=0.69)., Conclusion: Our results show an association between the studied C allele (ala110) and damage nerve in leprosy patients., Significance: Ninjurin analysis showed that asp110ala could be a valuable prognostic marker, since C allele (ala110) have increased susceptibility to nerve damage., (Copyright © 2012 Elsevier B.V. All rights reserved.)