Tuberculosis/COVID-19 co-infection detected in a single sputum sample using a rapid molecular test.

Tuberculosis (TB) and COVID-19 affect the lungs and are transmitted mainly by aerosols or particles of saliva from infected persons. Clinical similarities between diseases can affect correct diagnosis. Individuals belonging to the population deprived of liberty (PDL) are at increased risk of contagion due to precarious sanitary conditions and overcrowded environments. A variety of specimens may be suitable for the diagnosis of COVID-19, using molecular diagnostic techniques; however, there is little data on the analysis of sputum samples with the Xpert Xpress SARS-CoV-2® for the diagnosis of COVID-19, especially in this population group. The present study reports a case of TB and COVID-19 co-infection detected in sputum from an individual belonging to the PDL. For the detection, it used the GeneXpert platform (Cepheid, USA). Mycobacterium tuberculosis complex (MTC) was detected using the Xpert MTB/RIF Ultra® cartridge and SARS-CoV-2 was detected using the Xpert Xpress SARS-CoV-2® cartridge. The genes IS6110 and IS1081 were detected within 80 min indicating the presence of MTC, with no mutations related to resistance to rifampicin. The SARS-CoV-2 E and N2 genes were detected within 45 min. The result was confirmed by RT-qPCR with detection of E, N, and RdRP/S genes in the sputum and nasopharyngeal (NP) specimens. Rapid diagnoses that allow the identification and differentiation of such diseases are important for adequate epidemiological surveillance, isolation of infected individuals, and interruption of the transmission chain. Using the GeneXpert platform, specimens can be tested as soon as they are received, without the need for prior preparation. The US Food and Drug Administration has issued emergency authorization for the use of the Cepheid Xpert Xpress SARS-CoV-2 for the rapid detection of SARS-CoV-2 using specimens from a NP or nasal wash/aspirate. The case presented here gains an innovation with the use of the sputum to COVID-19 diagnosis.

Padronização da detecção molecular de Sars-Cov-2 em amostras de escarro de pacientes com suspeita de tuberculose em população privada de liberdade na região do ABC/SP / Standardization of molecular detection of Sars-Cov-2 in sputum samples from patients with suspected tuberculosis in a population deprived of liberty in the ABC/SP region

A tuberculose (TB) é das principais causas de morbidade e mortalidade no mundo, especialmente em países em desenvolvimento. O diagnóstico e o tratamento podem evitar milhões de mortes todos os anos. Há dois anos o SARS-CoV-2, um vírus que provoca uma infecção viral altamente transmissível e patogênica, que causa a doença denominada COVID-19 (relativa ao Coronavírus-19), causou a perda de um grande número de vidas em todo o mundo. Conforme a OMS, aproximadamente 80% dos acometidos pelo SARS-CoV-2 variaram de casos assintomáticos e manifestações clínicas leves a moderados, graves e críticos, e muitos foram a óbito. Sendo assim, é necessária atenção especial aos sinais e sintomas que indicam piora do quadro clínico e exijam a hospitalização. A infecção pelo Mycobacterium tuberculosis (MTB), principal agente da TB, que infecta de forma latente cerca de 25% da população global, incluindo a população privada de liberdade (PPL), pode ser um dos fatores agravantes da infecção pelo SARS-CoV-2. Esse estudo teve como objetivo padronizar, na plataforma GeneXpert, a utilização de amostras de escarro no diagnóstico molecular para detecção do SARS-CoV-2. A utilização do escarro para diagnóstico de SARS-CoV-2 poderá trazer benefícios ao paciente por ser uma coleta não invasiva, proporcionar a detecção de TB no mesmo material, permitindo o rápido isolamento do paciente para evitar transmissão e empregar o tratamento correto. Foram testadas 100 amostras de escarro de PPL para diagnóstico de TB e pesquisa de COVID-19 por metodologia padrão ouro (RT-qPCR) e teste rápido molecular (TRM-COVID). Destas, 12 amostras foram positivas para SARS-CoV-2 pela metodologia RT-qPCR e 13 amostras pelo TRM-COVID. Sete amostras foram positivas para o complexo Mycobacterium tuberculosis (CMTB) no TRM-TB e confirmadas pela cultura em meio líquido. Foi detectado um caso de coinfecção TB/COVID-19. O TRM-COVID apresentou sensibilidade de 90,9% quando utilizadas amostras de escarro para o diagnóstico da COVID-19. O teste pode agilizar o início do tratamento e os resultados rápidos permitem o 13 isolamento de indivíduos, a detecção de coinfecções TB/COVID-19 e o diagnóstico diferencial entre as doenças. (AU)

Tuberculosis (TB) is one of the main causes of morbidity and mortality in the world, especially in developing countries. Diagnosis and treatment can prevent millions of deaths every year. Two years ago, SARSCoV-2, a virus that causes a highly transmissible and pathogenic viral infection, which causes the disease called COVID-19 (relating to Coronavírus-19), caused the loss of a large number of lives throughout the world. According to the WHO, approximately 80% of those affected by SARS-CoV-2 ranged from asymptomatic cases and mild clinical manifestations to moderate, severe and critical, and many died. Therefore, special attention is needed to the signs and symptoms that indicate a worsening of the clinical condition and require hospitalization. Infection with Mycobacterium tuberculosis (MTB), the main agent of TB, which latently infects about 25% of the global population, including the population deprived of liberty, may be one of the aggravating factors of SARS-CoV-2 infection. This study aimed to standardize, on the GeneXpert platform, the use of sputum samples in molecular diagnosis for the detection of SARS-CoV-2. The use of sputum for diagnosis of SARS-CoV-2 may bring benefits to the patient as it is a non-invasive collection, providesthe detection of TB in the same material, allowing the rapid isolation of the patient to avoid transmission and employ the correct treatment. 100 sputum samples were tested from individuals deprived of liberty were tested for TB for TB diagnosis and COVID-19 research by gold standard methodology (RT-qPCR) and rapid molecular test (TRM-COVID). Of these, 12 samples were positive for SARSCoV- 2 by the RT-qPCR methodology and 13 samples by the TRM-COVID. Seven samples were positive for Mycobacterium tuberculosis complex (CMTB) on TRM-TB and confirmed by culture in liquid medium. One case of 15 TB/COVID-19 co-infection was detected. TRM-COVID showed a sensitivity of 90,9% when using sputum samples for the diagnosis of COVID-19. The test can expedite treatment initiation, and rapid results allow for isolation of individuals, detection of TB/COVID-19 co-infections, and differential diagnosis between diseases. (AU)

Viability assessment of Mycobacterium tuberculosis complex in OMNIgene • SPUTUM reagent using the BACTEC MGIT 960 System and Xpert MTB/RIF assay.

The World Health Organization advocates that sputum specimens submitted to tuberculosis (TB) diagnostic should be processed within 48 h after collection and be stored under cooling. We aimed to assess the performance of OMNIgene • SPUTUM reagent in maintaining viable specimens of Mycobacterium tuberculosis complex (MTBC) during transportation of sputum samples without refrigeration, in comparison to the standard protocol of the National TB Control Program. Sputum samples obtained in southeastern Brazil (June 2017 to July 2018) from 100 sequential patients with positive acid-fast bacillus smear microscopy were divided into two portions. Portion 1 continued to be cooled (standard protocol, STA), but portion 2 was added to OMNIgene • SPUTUM reagent (alternative protocol, OMS) until concomitant further processing. Both portions of all samples were cultured using MGIT and tested by Xpert MTB/RIF assay. Growth of MTBC in the first 42 days was detected in 96% of the cultures under the STA and 88% under the OMS. Intervals between processing and detecting MTBC growth in the two portions significantly differed (p = 0.0001). Portions under the two protocols showed similar results in the MTBC detection by Xpert assay and culture contamination by non-MTBC. The OMNIgene reagent liquefies and decontaminates sputum leading to a decrease in processing time. Although there was a small delay in mycobacterial growth, the OMNIgene reagent can be useful in specimens transported from collection sites over a long distance to centralized testing centers, maintaining viable MTBC for at least 8 days at room temperature.