Colchicine reduces the activation of NLRP3 inflammasome in COVID-19 patients.

OBJECTIVE: To evaluate whether colchicine treatment was associated with the inhibition of NLRP3 inflammasome activation in patients with COVID-19. METHODS: We present a post hoc analysis from a double-blinded placebo-controlled randomized clinical trial (RCT) on the effect of colchicine for the treatment of COVID-19. Serum levels of NOD-like receptor protein 3 (NLRP3) inflammasome products-active caspase-1 (Casp1p20), IL-1ß, and IL-18-were assessed at enrollment and after 48-72 h of treatment in patients receiving standard-of-care (SOC) plus placebo vs. those receiving SOC plus colchicine. The colchicine regimen was 0.5 mg tid for 5 days, followed by 0.5 mg bid for another 5 days. RESULTS: Thirty-six patients received SOC plus colchicine, and thirty-six received SOC plus placebo. Colchicine reduced the need for supplemental oxygen and the length of hospitalization. On Days 2-3, colchicine lowered the serum levels of Casp1p20 and IL-18, but not IL-1ß. CONCLUSION: Treatment with colchicine inhibited the activation of the NLRP3 inflammasome, an event triggering the 'cytokine storm' in COVID-19. TRIAL REGISTRATION NUMBERS: RBR-8jyhxh.

Noninvasive intracranial pressure monitoring for HIV-associated cryptococcal meningitis.

Mortality and adverse neurologic sequelae from HIV-associated cryptococcal meningitis (HIV-CM) remains high due to raised intracranial pressure (ICP) complications. Cerebrospinal fluid (CSF) high opening pressure occurs in more than 50% of HIV-CM patients. Repeated lumbar puncture with CSF drainage and external lumbar drainage might be required in the management of these patients. Usually, there is a high grade of uncertainty and the basis for clinical decisions regarding ICP hypertension tends to be from clinical findings (headache, nausea and vomiting), a low Glasgow coma scale score, and/or fundoscopic papilledema. Significant neurological decline can occur if elevated CSF pressures are inadequately managed. Various treatment strategies to address intracranial hypertension in this setting have been described, including: medical management, serial lumbar punctures, external lumbar and ventricular drain placement, and either ventricular or lumbar shunting. This study aims to evaluate the role of a non-invasive intracranial pressure (ICP-NI) monitoring in a critically ill HIV-CM patient.

Detection of katG and inhA mutations to guide isoniazid and ethionamide use for drug-resistant tuberculosis.

BACKGROUND: Depending on the presence of mutations that determine isoniazid (INH) susceptibility (katG and inhA), Mycobacterium tuberculosis may be susceptible to high doses of INH or ethionamide (ETH). OBJECTIVE: To describe the INH resistance profile and association of katG mutation with previous INH treatment and level of drug resistance based on rapid molecular drug susceptibility testing (DST) in southern Brazil and central Mozambique. DESIGN: Descriptive study of 311 isolates from Ribeirão Preto, São Paulo, Brazil (2011-2014) and 155 isolates from Beira, Mozambique (2014-2015). Drug resistance patterns and specific gene mutations were determined using GenoType(®) MTBDRplus. RESULTS: katG gene mutations were detected in 12/22 (54.5%) Brazilian and 32/38 (84.2%) Mozambican isolates. inhA mutations were observed in 9/22 (40.9%) isolates in Brazil and in 4/38 (10.5%) in Mozambique. Both katG and inhA mutations were detected in respectively 1/22 (5%) and 2/38 (5.2%). The difference in the frequency of katG mutations in Brazil and Mozambique was statistically significant (P = 0.04). katG mutations were present in 68.8% (33/48) of patients previously treated with INH and 31.2% (15/48) of patients without previous INH. This difference was not statistically significant (P = 0.223). CONCLUSION: INH mutations varied geographically; molecular DST can be used to guide and accelerate decision making in the use of ETH or high doses of INH.

Role of a GenoType MTBDRplus line probe assay in early detection of multidrug-resistant tuberculosis at a Brazilian reference center.

Resistance to Mycobacterium tuberculosis is a reality worldwide, and its diagnosis continues to be difficult and time consuming. To face this challenge, the World Health Organization has recommended the use of rapid molecular tests. We evaluated the routine use (once a week) of a line probe assay (Genotype MTBDRplus) for early diagnosis of resistance and for assessment of the main related risk factors over 2 years. A total of 170 samples were tested: 15 (8.8%) were resistant, and multidrug resistance was detected in 10 (5.9%). The sensitivity profile took 3 weeks (2 weeks for culture and 1 week for rapid testing). Previous treatment for tuberculosis and the persistence of positive acid-fast smears after 4 months of supervised treatment were the major risk factors observed. The use of molecular tests enabled early diagnosis of drug-resistant bacilli and led to appropriate treatment of the disease. This information has the potential to interrupt the transmission chain of resistant M. tuberculosis.

McFarland nephelometer as a simple method to estimate the sensitivity of the polymerase chain reaction using Mycobacterium tuberculosis as a research tool.

Polymerase chain reaction (PCR) has been widely investigated for the diagnosis of tuberculosis. However, before this technique is applied on clinical samples, it needs to be well standardized. We describe the use of McFarland nephelometer, a very simple approach to determine microorganism concentration in solution, for PCR standardization and DNA quantitation, using Mycobacterium tuberculosis as a model. Tuberculosis is an extremely important disease for the public health system in developing countries and, with the advent of AIDS, it has also become an important public health problem in developed countries. Using Mycobacterium tuberculosis as a research model, we were able to detect 3 M. tuberculosis genomes using the McFarland nephelometer to assess mycobacterial concentration. We have shown here that McFarland nephelometer is an easy and reliable procedure to determine PCR sensitivity at lower costs.

[Problems in the standardization of the polymerase chain reaction for the diagnosis of pulmonary tuberculosis]. / Problemas na padronização da reação em cadeia da polimerase para diagnóstico da tuberculose pulmonar.

INTRODUCTION: The recent increase in the number of tuberculosis cases has called the world's attention once again to a perennial health problem, especially prevalent in developing countries. The time elapsed between the diagnosis and the institution of therapy is an obstacle to tuberculosis control and there is an urgent need for the development of techniques for the disease's rapid diagnosis. To achieve this goal, molecular biology techniques have been exhaustively investigated. This work describes the use of a polymerase chain reaction for rapid diagnosis of tuberculosis in a developing country. The sensitivity and specificity of this technique is compared to standard techniques used in the microbiology laboratory. METHODS: This study was undertaken in Ribeirão Preto, S. Paulo State, Brazil. Forty-two sputum samples from suspected cases of tuberculosis attending the municipal health care centers were sent to the microbiology laboratory. The samples were processed for the detection of Mycobacterium tuberculosis by acid-fast bacilli determination, culture in Lowenstein-Jensen medium, and by a polymerase chain reaction that amplified a fragment of 123 base pairs of the Mycobacterium tuberculosis genome. RESULTS: Of the forty-two samples studied, one was contaminated and excluded from the study, ten were culture positive, ten were positive for the presence of acid-fast bacilli, and sixteen were polymerase chain reaction positive. The sensitivity and specificity of this technique were 90% and 81%, respectively. CONCLUSIONS: The polymerase chain reaction presented a sensitivity comparable to the culture and the whole procedure took only one day to complete. The results presented here make it a strong candidate for rapid diagnosis of tuberculosis in clinical settings making it possible to begin the specific therapy early in the course of the disease. However, standardization of the technique is necessary, and the correlation with clinical findings is of paramount importance due to the high sensitivity of this technique.

McFarland nephelometer as a simple method to estimate the sensitivity of the polymerase chain reaction using Mycobacterium tuberculosis as a research tool

Polymerase chain reaction (PCR) has been widely investigated for the diagnosis of tuberculosis. However, before this technique is applied on clinical samples, it needs to be well standardized. We describe the use of McFarland nephelometer, a very simple approach to determine microorganism concentration in solution, for PCR standardization and DNA quantitation, using Mycobacterium tuberculosis as a model. Tuberculosis is an extremely important disease for the public health system in developing countries and, with the advent of AIDS, it has also become an important public health problem in developed countries. Using Mycobacterium tuberculosis as a research model, we were able to detect 3 M. tuberculosis genomes using the McFarland nephelometer to assess micobacterial concentration. We have shown here that McFarland nephelometer is an easy and reliable procedure to determine PCR sensitivity at lower costs