Gene-Xpert Ultra for the diagnosis of extrapulmonary tuberculosis in children and adolescents

The Role of GeneXpert® for Tuberculosis Diagnostics in Brazil: An Examination from a Historical and Epidemiological Perspective

The rapid molecular test (RMT) performed on the GeneXpert® system is widely used as a control strategy and surveillance technique for tuberculosis (TB). In the region of the Americas, TB incidence is slowly increasing owing to an upward trend in Brazil, which is among the high TB-burden countries (HBCs), ranking in the 19th position. In this context, we aimed to (i) describe the implementation and history of RMT-TB (Xpert® MTB/RIF and Xpert® MTB/RIF Ultra) in Brazil; (ii) to evaluate the national RMT laboratory distribution, TB, and resistance to RIF detection by RMT; and (iii) to correlate these data with Brazilian TB incidence. The quantitative data of Xpert® MTB/RIF and Xpert® MTB/RIF Ultra assays performed in the pulmonary TB investigation from 2014 to 2020 were provided by the Brazilian Ministry of Health. A spatial visualization using ArcGIS software was performed. The Southeast region constituted about half of the RMT laboratories-from 39.4% to 45.9% of the total value over the five regions. Regarding the federal units, the São Paulo state alone represented from 20.2% to 34.1% (5.0 to 8.5 times the value) of RMT laboratories over the years observed. There were significant differences (p < 0.0001) in the frequency of RMT laboratories between all years of the historical series. There was an unequal distribution of RMT laboratories between Brazilian regions and federal units. This alerts us for the surveillance of rapid molecular detection of TB in different parts of the country, with the possibility of improving the distribution of tests in areas of higher incidence in order to achieve the level of disease control recommended by national and worldwide authorities.

Xpert MTB/RIF Ultra Trace Results: Decision Support for the Treatment of Extrapulmonary Tuberculosis in Low TB Burden Countries

OBJECTIVES

Extrapulmonary tuberculosis (EPTB) can be difficult to diagnose, especially in severe forms. The Xpert MTB/RIF Ultra test introduced an additional category called trace to reference very small amounts of Mycobacterium tuberculosis complex (MTBC) DNA. The objective of our multicenter study was to evaluate whether the trace result on an extrapulmonary (EP) sample is a sufficient argument to consider diagnosing tuberculosis and starting treatment, even in severe cases.

METHODS

A retrospective, multicenter cohort study was conducted from 2018 to 2022. Patients strongly suspected of EPTB with a trace result on an EP specimen were included. Hospital records were reviewed for clinical, treatment, and paraclinical data.

RESULTS

A total of 52 patients were included, with a severe form in 22/52 (42.3%) cases. Culture was positive for MTBC in 33/46 (71.7%) cases. Histological analysis showed granulomas in 36/45 (80.0%) cases. An Ultra trace result with a presumptive diagnosis of TB led to the decision to treat 41/52 (78.8%) patients. All patients were started on first-line anti-TB therapy (median duration of 6.1 months), with a favorable outcome in 31/35 (88.6%) patients. The presence of a small amount of MTBC genome in EPTB is a sufficient argument to treat patients across a large region of France.

Clinical forms and diagnosis of tuberculosis in children and adolescents during the COVID-19 pandemic

Objective: The present study aimed to describe the clinical forms and the time taken to diagnose new tuberculosis cases and to statistically analyze the isolated and combined forms of the disease in children and adolescents treated at a university hospital in Rio de Janeiro during the first year of the COVID-19 pandemic in Brazil. Methods: This was a cross-sectional study that used retrospective data on children (0-9 years old) and adolescents (10-18 years old) with pulmonary (PTB), extrapulmonary (EPTB), and combined tuberculosis (PTB + EPTB) followed up at the outpatient clinic from January 2019 to March 2021. Categorical data were analyzed by descriptive statistics and expressed as frequency and proportions. Categorical variables were compared using the Chi-square test, and numerical variables using Student's T-test. Results: A total of 51 cases were included, 63% (32/51) of which comprised patients in the year of the pandemic (group A), while 37% (19/51) were patients attended in previous years (group B). In group A, 19% (6/32) of the patients presented PTB, 59% (16/32) had EPTB, and 31% (10/32) had PTB+EPTB. In group B, 42% (8/19) of the patients presented PTB, 42% (8/19) had EPTB, and 16% (3/19) had PTB+EPTB. Conclusion: Our study revealed more tuberculosis cases in the first year of the pandemic than in the same period of the previous year, with greater variation of sites affected by the disease, including rarer and more severe forms.