2,3,5-triphenyl tetrazolium chloride as colorimetric indicator for drug susceptibility testing against nontuberculous mycobacteria.

This study aimed to propose and evaluate a drug susceptibility testing (DST) using the 2,3,5-triphenyl tetrazolium chloride (TTC) as a colorimetric indicator against Mycobacterium abscessus complex (MABC), M. avium complex (MAC), and M. kansasii strains, main nontuberculous mycobacteria (NTM) of clinical relevance. Our results demonstrated that the assay using TTC and the broth microdilution method recommended by the Clinical and Laboratory Standards Institute had essential agreement above 91%, 92%, and 100%, for drugs tested against MABC, MAC, and M. kansasii strains, respectively. Categorical agreement above 91% was obtained for most drugs tested against MABC, except to cefoxitin (76.5%). For drugs tested against MAC and M. kansasii, categorical agreement above 92% and 100% was observed, respectively. TTC showed to be a promising colorimetric indicator of growth to be used in DST for NTM, allowing an easier reading of results.

Genotyping methods and their contributions to the study of tuberculosis dynamic in Latin America.

INTRODUCTION: Mycobacterium tuberculosis genotyping has impacted evolutionary studies worldwide. Nonetheless, its application and the knowledge generated depend on the genetic marker evaluated and the detection technologies that have evolved over the years. Here we describe the timeline of main genotypic methods related to M. tuberculosis in Latin America and the main findings obtained. METHODOLOGY: Systematic searches through the PubMed database were performed from 1993 to May 2021. A total of 345 articles met the inclusion criteria and were selected. RESULTS: Spacer oligonucleotide typing (spoligotyping) was the most widely used method in Latin America, with decreasing use in parallel with increasing use of mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) and whole genome sequencing (WGS). Among the countries, Brazil, Mexico, and Argentina had the most publications, and a considerable part of the articles were in collaboration with Latin American or non-Latin American institutions; a small proportion of studies needed partnerships to perform the genotypic methods. The genotypic methods allowed the identification of M. tuberculosis genotypes with greater capacity for clonal expansion and revealed the predominance of the Euro-American lineage in Latin America. There was a notable presence of the Beijing family in Peru and Colombia. CONCLUSIONS: The data obtained demonstrated the importance of expanding collaborative networks of tuberculosis (TB) research groups to countries with low productivity in this area, the commitment of the few Latin American countries to advance TB research, as well as the inestimable value of building a Latin America database, considering ease of population mobility between countries.

Prevalence of Overweight and Associated Factors in a Male Prison Population in the Extreme South of Brazil: A Cross-Sectional Study.

Background: This cross-sectional study serves as a first Brazilian inventory about overweight as a marker for metabolic health and risk factor to develop noncommunicable chronic diseases in prison populations. The prevalence of overweight, and its associated factors in prisoners of the Fifth Regional State Penitentiary of Rio Grande do Sul (5th DPR) in the extreme South of Brazil were investigated using a precoded questionnaire with sociodemographic, behavioral, and health questions, applied to proportional stratified random sampled prisoners. Methods: Five hundred eighty male prisoners (70%) in the closed regime agreed to answer the questionnaire and allowed anthropomorphic body measurement, carried out by trained scientists. We used bivariate Pearson's chi-squared test and adjusted multinomial logistic regression for analyses. Results: Considering that the studied incarcerated population is young (mean age 33 years) it is concerning that already 43.6% of them are overweight, report regular sweets and sugary soft drink consumption (77.7%, and 81.4%, respectively), 60.2% are smokers, and 19.4% are at elevated risk to develop cardiovascular diseases. Further, 13.8% of the respondents reported a diagnosis of hypertension, 4.9% hypercholesterolemia, and 2.7% diabetes mellitus type 2. Among those who reported not smoking, excess weight was almost four times higher (prevalence ratio: 3.79; 95% confidence interval: 2.61-5.50). Conclusions: Our study suggests that the prison environment promotes modifiable risk factors for chronic diseases. These data deserve attention and intervention, aiming to prevent and reduce the current levels of excess weight.

Epidemiology and control strategies for tuberculosis in countries with the largest prison populations.

Tuberculosis (TB) is a serious infectious disease, and its control is considered a challenge, especially among vulnerable populations such as prisoners. The occurrence of TB in prisons is an alarming public health problem in many countries. This integrative review aims to describe the epidemiology of TB and control strategies for this disease in countries with the largest prison populations. Studies have shown that it is essential to know the prevalence of TB in prisons of each country. This is because it can serve as an indication of the need for action in prisons to reduce TB rates, including improving the structure of prison environments, rapidly and accurately diagnosing new cases, identifying drug-resistant strains, and implementing effective and directly observed treatment for TB.

Epidemiology and control strategies for tuberculosis in countries with the largest prison populations

ABSTRACT Tuberculosis (TB) is a serious infectious disease, and its control is considered a challenge, especially among vulnerable populations such as prisoners. The occurrence of TB in prisons is an alarming public health problem in many countries. This integrative review aims to describe the epidemiology of TB and control strategies for this disease in countries with the largest prison populations. Studies have shown that it is essential to know the prevalence of TB in prisons of each country. This is because it can serve as an indication of the need for action in prisons to reduce TB rates, including improving the structure of prison environments, rapidly and accurately diagnosing new cases, identifying drug-resistant strains, and implementing effective and directly observed treatment for TB.

Whole-genome sequencing as a tool for studying the microevolution of drug-resistant serial Mycobacterium tuberculosis isolates.

Treatment of drug-resistant tuberculosis requires extended use of more toxic and less effective drugs and may result in retreatment cases due to failure, abandonment or disease recurrence. It is therefore important to understand the evolutionary process of drug resistance in Mycobacterium tuberculosis. We here in describe the microevolution of drug resistance in serial isolates from six previously treated patients. Drug resistance was initially investigated through phenotypic methods, followed by genotypic approaches. The use of whole-genome sequencing allowed the identification of mutations in the katG, rpsL and rpoB genes associated with drug resistance, including the detection of rare mutations in katG and mixed populations of strains. Molecular docking simulation studies of the impact of observed mutations on isoniazid binding were also performed. Whole-genome sequencing detected 266 single nucleotide polymorphisms between two isolates obtained from one patient, suggesting a case of exogenous reinfection. In conclusion, sequencing technologies can detect rare mutations related to drug resistance, identify subpopulations of resistant strains, and identify diverse populations of strains due to exogenous reinfection, thus improving tuberculosis control by guiding early implementation of appropriate clinical and therapeutic interventions.

2,2,2-trifluoro-1-(1,4,5,6-tetrahydropyridin-3-yl)ethanone derivative as efflux pump inhibitor in Mycobacterium tuberculosis.

Although the administration of combined therapy is efficient to tuberculosis (TB) treatment caused by susceptible Mycobacterium tuberculosis strains, to overcome the multidrug resistance is still a challenge. Some studies have reported evidence about tetrahydropyridines as a putative efflux pump inhibitor, including in mycobacteria, being a promising strategy against M. tuberculosis. Thus, we investigated the biological potential of 2,2,2-trifluoro-1-(1,4,5,6-tetrahydropyridin-3-yl)ethanone derivative (NUNL02) against two strains of M. tuberculosis. NUNL02 was able to increase the susceptibility of the multidrug resistant strain to the anti-TB drugs, resulting in synergism with rifampicin. Still, we assume that this compound plays a role in the efflux mechanism in M. tuberculosis, besides, to be able to kill the bacillus under the deprivation of essential nutrients. Thus, our findings highlight NUNL02 as a promising prototype to develop a new adjuvant for TB treatment, mainly as EPI.

Female insertion in neurosurgery: Evolution of a stigma break.

BACKGROUND: Utilizing the Brazilian Medical Demography analysis and a literature review, we evaluated how women choose to become neurosurgeons in Brazil and around the world, specifically citing the Europe, the USA, India, and Japan. METHODS: We utilized the Brazilian Medical Demography prepared by the Federal Council of Medicine and the Regional Council of Medicine of the State of São Paulo (2011, 2013, 2015, and 2018). We also included an evaluation of 20 articles from PubMed, the Scientific Electronic Library Online, and National Health Library databases (e.g., using descriptors "Women in neurosurgery" and "Career"). RESULTS: In Brazil in 2017, women comprised 45.6% of active doctors, but only 8.6% of all neurosurgeons. Of 20 articles identified in the literature, 50% analyzed the factors that influenced how women choose neurosurgery, 40% dealt with gender differences, while just 10% included an analysis of what it is like to be a female neurosurgeon in different countries/continents. CONCLUSION: The participation of women in neurosurgery has increased in recent years despite the persistence of gender inequality and prejudice. More women need to be enabled to become neurosurgeons as their capabilities, manual dexterity, and judgment should be valued to improve the quality of neurosurgical health-care delivery.

Laboratory diagnosis for Covid-19: A mini-review.

Coronavirus disease (COVID-19) is a pandemic caused by a new coronavirus, called SARS-CoV-2. This disease was first identified in December 2019 and rapidly developed into a challenge to the public health systems around the world. In the absence of a vaccine and specific therapies, disease control and promotion of patient health are strongly dependent on a rapid and accurate diagnosis. This review describes the main laboratory approaches to making a diagnosis of COVID-19 and identifying those previously infected with SARS-CoV-2.

Nontuberculous mycobacteria in patients with suspected tuberculosis and the genetic diversity of Mycobacterium avium in the extreme south of Brazil.

OBJECTIVE: Nontuberculous mycobacteria (NTM) are a heterogeneous group of bacteria that are widely distributed in nature and associated with opportunistic infections in humans. The aims of this study were to identify NTM in patients with suspected tuberculosis who presented positive cultures and to evaluate the genetic diversity of strains identified as Mycobacterium avium. METHODS: We studied pulmonary and extrapulmonary samples obtained from 1,248 patients. The samples that tested positive on culture and negative for the M. tuberculosis complex by molecular identification techniques were evaluated by detection of the hsp65 and rpoB genes and sequencing of conserved fragments of these genes. All strains identified as M. avium were genotyped using the eight-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat method. RESULTS: We found that NTM accounted for 25 (7.5%) of the 332 mycobacteria isolated. Of those 25, 18 (72%) were M. avium, 5 (20%) were M. abscessus, 1 (4%) was M. gastri, and 1 (4%) was M. kansasii. The 18 M. avium strains showed high diversity, only two strains being genetically related. CONCLUSIONS: These results highlight the need to consider the investigation of NTM in patients with suspected active tuberculosis who present with positive cultures, as well as to evaluate the genetic diversity of M. avium strains.

Histoplasma capsulatum and Mycobacterium avium co-infection in an immunocompromised patient: Case report and literature review.

We report a case of fungal and mycobacterial co-infection in an immunosuppressed patient from Southern Brazil. Histoplasmosis was diagnosed in an AIDS patient admitted to the hospital with nonspecific respiratory signs. However, 4 months post hospital discharge, the patient worsened and a co-infection with Mycobacterium avium was detected. Physicians must consider and investigate a broad spectrum of diseases which can occur as co-infections and which share the same clinical symptoms and signs in immunosuppressed patients.

The role of urea-induced osmotic diuresis and hypernatremia in a critically ill patient: case report and literature review.

Hypernatremia is a common electrolyte problem at the intensive care setting, with a prevalence that can reach up to 25%. It is associated with a longer hospital stay and is an independent risk factor for mortality. We report a case of hypernatremia of multifactorial origin in the intensive care setting, emphasizing the role of osmotic diuresis due to excessive urea generation, an underdiagnosed and a not well-known cause of hypernatremia. This scenario may occur in patients using high doses of corticosteroids, with gastrointestinal bleeding, under diets and hyperprotein supplements, and with hypercatabolism, especially during the recovery phase of renal injury. Through the present teaching case, we discuss a clinical approach to the diagnosis of urea-induced osmotic diuresis and hypernatremia, highlighting the utility of the electrolyte-free water clearance concept in understanding the development of hypernatremia.

Laboratory diagnosis for Covid-19: A mini-review

Abstract Coronavirus disease (COVID-19) is a pandemic caused by a new coronavirus, called SARS-CoV-2. This disease was first identified in December 2019 and rapidly developed into a challenge to the public health systems around the world. In the absence of a vaccine and specific therapies, disease control and promotion of patient health are strongly dependent on a rapid and accurate diagnosis. This review describes the main laboratory approaches to making a diagnosis of COVID-19 and identifying those previously infected with SARS-CoV-2.

Chronic Inflammatory Arthropathy Preceding Acute Systemic Manifestations of Sarcoidosis: A Possible Overlap of Idiopathic Juvenile Arthritis and Sarcoidosis.

Sarcoidosis is a multisystem disease with unknown etiology, marked by T lymphocytes and macrophages agglomeration, which leads to the formation of noncaseating granulomas in the affected tissues. We describe a case of a 40-year-old black patient referred to our service for evaluation of nephrolithiasis and persistent elevation of plasma creatinine. He reported important weight loss, fever episodes, and abdominal and low back intermittent pain in the past 6 months. The investigation revealed elevated serum calcium level, hepatosplenomegaly, retroperitoneal lymphadenopathy, anemia, thrombocytopenia, and nephrolithiasis. The initial diagnostic hypothesis was lymphoproliferative disease, but the laparoscopic propaedeutic showed multiple white lesions on the liver surface, which biopsy identified as noncaseating granulomas with asteroid corpuscles, suggestive of sarcoidosis. He was treated with corticosteroids with significant improvement in symptoms and in calcium and creatinine levels. Besides, the patient presented a long-term large joints arthropathy, especially on the knees (with bilateral prosthesis), wrists, and ankles, of unknown etiology. We discuss the systemic manifestations of sarcoidosis related to the reported case, as well as the possible overlapping of idiopathic juvenile arthritis with sarcoidosis.

The Contribution of Efflux Pumps in Mycobacterium abscessus Complex Resistance to Clarithromycin.

The basis of drug resistance in Mycobacterium abscessus is still poorly understood. Nevertheless, as seen in other microorganisms, the efflux of antimicrobials may also play a role in M. abscessus drug resistance. Here, we investigated the role of efflux pumps in clarithromycin resistance using nine clinical isolates of M. abscessus complex belonging to the T28 erm(41) sequevar responsible for the inducible resistance to clarithromycin. The strains were characterized by drug susceptibility testing in the presence/absence of the efflux inhibitor verapamil and by genetic analysis of drug-resistance-associated genes. Efflux activity was quantified by real-time fluorometry. Efflux pump gene expression was studied by RT-qPCR upon exposure to clarithromycin. Verapamil increased the susceptibility to clarithromycin from 4- to ≥64-fold. The efflux pump genes MAB_3142 and MAB_1409 were found consistently overexpressed. The results obtained demonstrate that the T28 erm(41) polymorphism is not the sole cause of the inducible clarithromycin resistance in M. abscessus subsp. abscessus or bolletii with efflux activity providing a strong contribution to clarithromycin resistance. These data highlight the need for further studies on M. abscessus efflux response to antimicrobial stress in order to implement more effective therapeutic regimens and guidance in the development of new drugs against these bacteria.

In silico and in vitro evaluation of tetrahydropyridine compounds as efflux inhibitors in Mycobacterium abscessus.

Herein, we evaluated tetrahydropyridine (THP) compounds (NUNM) as antimicrobials and inhibitors of the efflux mechanism in M. abscessus. subsp. abscessus. The modulation factor (MF) of efflux inhibitors was calculated from the minimum inhibitory concentrations (MICs) of amikacin (AMI), ciprofloxacin (CIP) and clarithromycin (CLA) in the absence and presence of subinhibitory concentrations of the NUNM compounds and canonical inhibitors carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and verapamil (VP). The kinetics of the intracellular accumulation of the fluorimetric substrate ethidium bromide (EtBr) was evaluated and calculated by the relative final fluorescence (RFF). In addition, molecular modeling simulations for the MmpL5 and Tap efflux transporters with ligands (CLA, NUNM, CCCP, VP and EtBr) were performed to better understand the efflux mechanism. We highlight the NUNM01 compound because it reduced the MICs of AMI, CIP and CLA by 4-, 4- and 16-fold, respectively, had the highest effect on EtBr accumulation (RFF = 3.1) and showed a significant in silico affinity for the evaluated proteins in docking simulations. Based on the analyses performed in vitro and in silico, we propose that NUNM01 is a potential pharmacophore candidate for the development of a therapeutic adjuvant for M. abscessus infections.

Atypical presentation of familial hypomagnesemia with hypercalciuria and nephrocalcinosis in a patient with a new claudin-16 gene mutation.

Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is an autosomal recessive tubular disorder caused by mutations in genes that encode renal tight junction proteins claudin-16 or claudin-19, which are responsible for magnesium and calcium paracellular reabsorption in the thick ascending limb of Henle's loop. Progressive renal failure is frequently present, and most of the patients require renal replacement therapy still during adolescence. In this case report, we describe a new homozygous missense mutation on CLDN16 gene (c.592G>C, Gly198Arg) in a 24-year-old male patient diagnosed with FHHNC after clinical investigation due to incidental detection of altered routine laboratorial tests, who was firstly misdiagnosed with primary hyperparathyroidism. In addition, it illustrates an atypical presentation of this disease, with late onset of chronic kidney disease, improving the phenotype-genotype knowledge of patients with FHHNC.

Mycobacterium avium: an overview.

Mycobacterium avium is an environmental microorganism found in soil and water sources worldwide. It is the most prevalent species of nontuberculous mycobacteria that causes infectious diseases, especially in immunocompromised individuals. This review discusses and highlights key topics about M. avium, such as epidemiology, pathogenicity, glycopeptidolipids, laboratory identification, genotyping, antimicrobial therapy and antimicrobial resistance. Additionally, the main comorbidities associated with M. avium infection are discussed.

Tetrahydropyridine derivative as efflux inhibitor in Mycobacterium abscessus.

OBJECTIVES: This study aimed to evaluate a tetrahydropyridine derivative (THP) as a potential inhibitor of the efflux mechanism and modulator of the high level of antimicrobial resistance usually observed in members of the Mycobacterium abscessus (M. abscessus) group. METHODS: The strain M. abscessus subsp. abscessus (ATCC 19997) was used as reference, in addition to three clinical isolates: M. abscessus subsp. abscessus (AT 07), and two M. abscessus subsp. bolletii (AT 46 and AT 52). The minimum inhibitory concentration (MIC) of amikacin (AMI), ciprofloxacin (CIP), clarithromycin (CLA), verapamil (VP), and THP derivative (NUNL02) was determined. RESULTS: The NUNL02 showed activity against M. abscessus; the MIC of AMI against ATCC 19997 was reduced more than 16-fold, and the MIC of CIP against AT 52 was reduced four-fold. When combined with CLA, the MIC was reduced against all tested strains. In addition, to detect and quantify the activity of the efflux mechanism, the intracellular accumulation kinetics of the fluorometric substrate ethidium bromide in the presence and absence of VP and NUNL02 were evaluated. The NUNL02 was found to be a more effective efflux inhibitor than VP, which is the classical inhibitor. CONCLUSIONS: The tetrahydropyridine derivative, NUNL02, is a promising adjuvant in the treatment of infections caused by M. abscessus.