A randomised controlled trial of stepwise sputum collection to increase yields of confirmed tuberculosis

Evaluation of the Cepheid 3-gene host response blood test for tuberculosis diagnosis and treatment response monitoring in a primary-level clinic in rural China

A rapid, accurate, non-sputum-based triage test for diagnosing tuberculosis (TB) is a high-priority need. Cepheid developed a novel prototype blood test, Xpert Mycobacterium tuberculosis Host Response (Xpert-MTB-HR), which generates a TB score based on the mRNA expression of three genes. We conducted a case-control study with prospective recruitment to evaluate its accuracy in the clinic of the Wusheng County Centers for Disease Prevention and Control in China. We enrolled 149 TB patients, 248 other respiratory diseases (ORD) patients, and 193 healthy controls. In addition, whole-blood samples taken from TB patients after 2, 5, and 6 months of treatment were tested with Xpert-MTB-HR to evaluate its ability to monitor treatment response. Xpert-MTB-HR discriminated between TB and healthy controls with an area under the curve (AUC) of 0.912 (95% CI, 0.878-0.945). With the specificity of 70% envisioned for a triage test, its sensitivity was 90.1% (84.9%-94.6%). Xpert-MTB-HR discriminated between TB and ORD with an AUC of 0.798 (0.750-0.847), and at specificity of 70%, the sensitivity was only 75.8% (68.5%-82.8%). In patients determined by Ultra to have medium or high sputum bacillary loads, with specificity of 70%, the sensitivity for discriminating patients with TB from healthy controls was 100.0% (100.0-100.0) and from patients with ORD, 95.1% (89.8-100.0). The TB scores generally increased by 2 months of treatment and then remained stable. Xpert-MTB-HR met the criteria for a triage test to discriminate between TB and healthy controls, but not between TB and ORD, except when limited to patients with high sputum bacillary loads. Xpert-MTB-HR showed promise for monitoring response to treatment but needs to be further evaluated in larger prospective studies.

Comparison of Xpert MTB/RIF Ultra with Xpert MTB/RIF for the detection of Mycobacterium tuberculosis and rifampicin resistance in a primary-level clinic in rural China

The Xpert MTB/RIF Ultra (Ultra) is not yet used for the diagnosis of tuberculosis (TB) in China. We compared the performance of the Xpert and Ultra for detecting Mycobacterium tuberculosis and rifampicin resistance in a primary-level clinic in rural China. Sputum samples from suspected pulmonary TB patients were collected and subjected to smear microscopy, liquid culture, Xpert and Ultra tests. We then compared the sensitivity and specificity of Xpert and Ultra for diagnosing TB against liquid culture. Whole-genome sequencing was performed to predict rifampicin resistance and the results were compared with the Xpert and Ultra tests. The sensitivities of Xpert and Ultra were 88.1% and 95.1%, and the specificities were 91.9% and 84.4%, respectively. Among the 61 smear-negative culture-positive patients, the sensitivities of Xpert and Ultra were 80.3% and 91.8%. All Xpert-positive patients were Ultra-positive. Among culture-negative Xpert or Ultra-positive patients, 69.6% were taking anti-TB drugs or had a previous history of TB. Of the samples that Ultra classified as trace, nearly 25% were probably false-positives. Both Xpert and Ultra accurately detected all rifampicin-resistant patients. In conclusion, Ultra was more sensitive than Xpert, especially for smear-negative patients but had decreased specificity with more false-positives, especially with Ultra trace results.

Desenvolvimento e validação de um folder educativo para coleta de escarro da tuberculose pulmonar

RESUMO Objetivo: desenvolver e validar um folder educativo para coleta de escarro da tuberculose pulmonar. Método: estudo metodológico, desenvolvido em quatro fases: elaboração do projeto, levantamento bibliográfico, desenvolvimento e validação de conteúdo e aparência. Para validação, adotaram-se o Índice de Validade de Conteúdo maior ou igual a 0,80, o Coeficiente Kappa e o Suitability Assessment of Materials. Resultados: desenvolveu-se um folder educativo contendo os passos recomendados para coleta de escarro de qualidade. Esse foi validado, por 19 juízes especialistas, no primeiro ciclo de validação, ao obter Índice de Validade de Conteúdo global de 0,90, concordância perfeita entre os juízes, com Kappa total de 0,83 e adequação superior. Conclusão: o material é válido, pois contém linguagem, ilustrações e layout adequados, simples e atraentes, indicando concordância e confiabilidade perfeita. Assim, apresenta potencialidade para auxiliar na realização dos passos recomendados para correta coleta de escarro e possibilitar o diagnóstico correto.

Development and validity of an educational folder for pulmonary tuberculosis sputum collection

OBJECTIVE

to develop and validate an educational folder for pulmonary tuberculosis sputum collection.

METHOD

a methodological study, developed in four phases: project design, bibliographic survey, development, and content and appearance validity. For validity, the Content Validity Index greater than or equal to 0.80, the Kappa Coefficient and the Suitability Assessment of Materials were adopted.

RESULTS

an educational folder was developed containing the recommended steps for quality sputum collection. It was validated by 19 expert judges in the first validity cycle, obtaining an overall Content Validity Index of 0.90, perfect agreement among judges, with a total Kappa of 0.83 and superior suitability.

CONCLUSION

the material is valid, as it contains suitable, simple and attractive language, illustrations and layout, indicating perfect agreement and reliability. Thus, it has the potential to assist in carrying out the recommended steps for correct sputum collection and enable the correct diagnosis.

High proportion of tuberculosis transmission among social contacts in rural China: a 12-year prospective population-based genomic epidemiological study

Tuberculosis (TB) is more prevalent in rural than urban areas in China, and delineating TB transmission patterns in rural populations could improve TB control. We conducted a prospective population-based study of culture-positive pulmonary TB patients diagnosed between July 1, 2009 and December 31, 2020 in two rural counties in China. Genomic clusters were defined with a threshold distance of 12-single-nucleotide-polymorphisms, based on whole-genome sequencing. Risk factors for clustering were identified by logistic regression. Transmission links were sought through epidemiological investigation of genomic-clustered patients. Of 1517 and 751 culture-positive pulmonary TB patients in Wusheng and Wuchang counties, respectively, 1289 and 699 strains were sequenced. Overall, 624 (31.4%, 624/1988) patients were grouped into 225 genomic clusters. Epidemiological links were confirmed in 41.8% (196/469) of clustered isolates, including family (32.7%, 64/196) and social contacts (67.3%, 132/196). Social contacts were generally with relatives, within the community or in shared aggregated settings outside the community, but the proportion of clustered contacts in each category differed between the two sites. The time interval between diagnosis of student cases and contacts was significantly shorter than family and social contacts, probably due to enhanced student contact screening. Transmission of multidrug-resistant (MDR) strains was likely responsible for 81.4% (83/102) of MDR-TB cases, with minimal acquisition of additional resistance mutations. A large proportion of TB transmission in rural China occurred among social contacts, suggesting that active screening and aggressive contact tracing could benefit TB control, but contact screening should be tailored to local patterns of social interactions.

Educational technologies to guide pulmonary tuberculosis sputum collection: a systematic review

OBJECTIVE

To evaluate the contributions of educational technologies used during the guidelines for sputum collection from pulmonary tuberculosis.

METHOD

Systematic review guided by Preferred Reporting items for Systematic Reviews with protocol registered in the database International Prospective Register of Systematic Reviews, with number CRD42020208162. The search was performed in the Cinahl, Scopus, PubMed, Web of Science, Embase, Lilacs, CENTRAL, CAPES, Proquest, OpenGrey databases and manual search in the reference list. The search, selection of studies, data extraction, and methodological evaluation using the Cochrane Risk-of-Bias tool were performed by two independent reviewers.

RESULTS

A total of 2,488 studies were evidenced, with seven being selected and analyzed, of which four used structured lectures; three, educational booklet; and one, an educational video, used alone or together, impacting the bacteriological confirmation of tuberculosis. The studies had a low risk of bias.

CONCLUSION

Scientific evidence has shown that educational technologies contribute to increasing the quality, volume, and appearance of the sputum sample, which improves the bacteriological confirmation of the disease.

Tecnologias educativas para orientação da coleta de escarro da tuberculose pulmonar: revisão sistemática

RESUMO Objetivo: Avaliar as contribuições das tecnologias educativas utilizadas durante as orientações para coleta de escarro da tuberculose pulmonar. Método: Revisão sistemática guiada pelo Preferred Reporting items for Systematic Reviews com protocolo registrado na base International Prospective Register of Systematic Reviews, sob o número CRD42020208162. A busca foi realizada nas bases de dados Cinahl, Scopus, PubMed, Web of Science, Embase, Lilacs, CENTRAL, CAPES, Proquest, OpenGrey e busca manual na lista de referências. A busca, seleção dos estudos, extração dos dados e avaliação metodológica pela ferramenta do Risco de Viés da Cochrane foram realizadas por dois revisores independentes. Resultados: Evidenciaram-se 2488 estudos, sendo sete selecionados e analisados, dos quais quatro utilizaram palestras estruturadas; três, folder educativo; e um, vídeo educativo. Todos foram utilizados de forma isolada ou em conjunto, impactando na confirmação bacteriológica da tuberculose. Os estudos apresentaram baixo risco de viés. Conclusão: As evidências científicas demonstraram que as tecnologias educativas apresentam como contribuições o aumento da qualidade, volume e aspecto da amostra de escarro, o que proporciona a melhoria da confirmação bacteriológica da doença.