Diagnostic accuracy of the Cepheid 3-gene host response fingerstick blood test in a prospective, multi-site study: interim results.

BACKGROUND: The development of a fast and accurate, non-sputum-based point-of-care triage test for tuberculosis (TB) would have a major impact on combating the TB burden worldwide. A new fingerstick blood test has been developed by Cepheid (the Xpert-MTB-Host Response (HR)-Prototype), which generates a 'TB score' based on mRNA expression of 3 genes. Here we describe the first prospective findings of the MTB-HR prototype. METHODS: Fingerstick blood from adults presenting with symptoms compatible with TB in South Africa, The Gambia, Uganda and Vietnam was analysed using the Cepheid GeneXpert MTB-HR prototype. Accuracy of the Xpert MTB-HR cartridge was determined in relation to GeneXpert Ultra results and a composite microbiological score (GeneXpert Ultra and liquid culture) with patients classified as having TB or other respiratory diseases (ORD). RESULTS: When data from all sites (n=75 TB, 120 ORD) were analysed, the TB score discriminated between TB and ORD with an AUC of 0·94 (CI, 0·91-0·97), sensitivity of 87% (CI, 77-93%) and specificity of 94% (88-97%). When sensitivity was set at 90% for a triage test, specificity was 86% (CI, 75-97%). These results were not influenced by HIV status or geographical location. When evaluated against a composite microbiological score (n=80 TB, 111 ORD), the TB score was able to discriminate between TB and ORD with an AUC of 0·88 (CI, 0·83-0·94), 80% sensitivity (CI, 76-85%) and 94% specificity (CI, 91-96%). CONCLUSIONS: Our interim data indicate the Cepheid MTB-HR cartridge reaches the minimal target product profile for a point of care triage test for TB using fingerstick blood, regardless of geographic area or HIV infection status

Diagnostic Accuracy of the Cepheid 3-gene Host Response Fingerstick Blood Test in a Prospective, Multi-site Study: Interim Results

This study is the first prospective evaluation of the Cepheid MTB-HR test using fingerstick blood in a multi-site cohort. Interim results indicate the test reaches the WHO TPP for a TB Triage test regardless of geographical location and HIV status.Background The development of a fast and accurate, non-sputum-based point-of-care triage test for tuberculosis (TB) would have a major impact on combating the TB burden worldwide. A new fingerstick blood test has been developed by Cepheid (the Xpert MTB Host Response [MTB-HR] prototype), which generates a "TB score" based on messenger RNA (mRNA) expression of 3 genes. Here we describe the first prospective findings of the MTB-HR prototype. Methods Fingerstick blood from adults presenting with symptoms compatible with TB in South Africa, The Gambia, Uganda, and Vietnam was analyzed using the Cepheid GeneXpert MTB-HR prototype. Accuracy of the Xpert MTB-HR cartridge was determined in relation to GeneXpert Ultra results and a composite microbiological score (GeneXpert Ultra and liquid culture) with patients classified as having TB or other respiratory diseases (ORD). Results When data from all sites (n = 75 TB, 120 ORD) were analyzed, the TB score discriminated between TB and ORD with an area under the curve (AUC) of 0.94 (95% confidence interval [CI], .91-.97), sensitivity of 87% (95% CI, 77-93%) and specificity of 94% (88-97%). When sensitivity was set at 90% for a triage test, specificity was 86% (95% CI, 75-97%). These results were not influenced by human immunodeficiency virus (HIV) status or geographical location. When evaluated against a composite microbiological score (n = 80 TB, 111 ORD), the TB score was able to discriminate between TB and ORD with an AUC of 0.88 (95% CI, .83-.94), 80% sensitivity (95% CI, 76-85%) and 94% specificity (95% CI, 91-96%). Conclusions Our interim data indicate the Cepheid MTB-HR cartridge reaches the minimal target product profile for a point of care triage test for TB using fingerstick blood, regardless of geographic area or HIV infection status

Diagnostic Accuracy of the Cepheid 3-gene Host Response Fingerstick Blood Test in a Prospective, Multi-site Study: Interim Results

This study is the first prospective evaluation of the Cepheid MTB-HR test using fingerstick blood in a multi-site cohort. Interim results indicate the test reaches the WHO TPP for a TB Triage test regardless of geographical location and HIV status.Background The development of a fast and accurate, non-sputum-based point-of-care triage test for tuberculosis (TB) would have a major impact on combating the TB burden worldwide. A new fingerstick blood test has been developed by Cepheid (the Xpert MTB Host Response [MTB-HR] prototype), which generates a "TB score" based on messenger RNA (mRNA) expression of 3 genes. Here we describe the first prospective findings of the MTB-HR prototype. Methods Fingerstick blood from adults presenting with symptoms compatible with TB in South Africa, The Gambia, Uganda, and Vietnam was analyzed using the Cepheid GeneXpert MTB-HR prototype. Accuracy of the Xpert MTB-HR cartridge was determined in relation to GeneXpert Ultra results and a composite microbiological score (GeneXpert Ultra and liquid culture) with patients classified as having TB or other respiratory diseases (ORD). Results When data from all sites (n = 75 TB, 120 ORD) were analyzed, the TB score discriminated between TB and ORD with an area under the curve (AUC) of 0.94 (95% confidence interval [CI], .91-.97), sensitivity of 87% (95% CI, 77-93%) and specificity of 94% (88-97%). When sensitivity was set at 90% for a triage test, specificity was 86% (95% CI, 75-97%). These results were not influenced by human immunodeficiency virus (HIV) status or geographical location. When evaluated against a composite microbiological score (n = 80 TB, 111 ORD), the TB score was able to discriminate between TB and ORD with an AUC of 0.88 (95% CI, .83-.94), 80% sensitivity (95% CI, 76-85%) and 94% specificity (95% CI, 91-96%). Conclusions Our interim data indicate the Cepheid MTB-HR cartridge reaches the minimal target product profile for a point of care triage test for TB using fingerstick blood, regardless of geographic area or HIV infection status.Immunogenetics and cellular immunology of bacterial infectious disease