The Role of Clinical Suspicion in Evaluating a New Diagnostic Test for Active Tuberculosis

Abstract

For complex diagnostic problems like TB, clinical risk assessments can provide important information regarding predictive values more likely to be experienced in clinical practice. For this series, a clinical suspicion of TB was helpful in targeting areas of the clinical spectrum in which nucleic acid amplification tests can make an important contribution.

PCR colorimetric dot-blot assay and clinical pretest probability for diagnosis of Pulmonary Tuberculosis in Smear-Negative patients

“…We conclude that our results are in agreement with those of the literature, showing that molecular methods may provide an important contribution to the diagnosis of SNPTB in patients with high clinical suspicion [ 24 , 26 ]. Since home-made PCR is less costly than automated NAA, this test could be introduced more widely after a proper evaluation of its cost-effectiveness with clinical and radiographic characteristics to refine estimates of likelihood of TB disease in different settings, as proposed by others [ 28 , 34 ].…”

“…In this study, when we used PCR in parallel with high pretest probability, the diagnostic appeared to offer a higher negative predictive value in SNPTB subjects that had not been previously treated and in HIV seronegative cases, as described by others [ 24 , 25 , 30 ]. In non-previously treated and HIV seronegative cases, the performance results (SE: 93%; NPV: 92%) were similar to those recently described by Piersimoni et al, using automated tests in 214 PTB suspects [ 26 ].…”

A Toolbox for Tuberculosis (TB) Diagnosis: An Indian Multicentric Study (2006–2008). Evaluation of QuantiFERON-TB Gold in Tube for TB Diagnosis

“…As already shown by Catanzaro and colleagues [29], the varying degree of a physician’s CSTB has a definite influence on the accuracy clinical symptoms, radiological findings and microbiological tools and was confirmed in our preceding study [8]. In contrast, in our present study the varying degree of a physician’s clinical suspicion of TB has no influence on the accuracy of the QFT-GIT.…”

What is the optimal approach for using a direct amplification test in the routine diagnosis of pulmonary tuberculosis? A preliminary assessment

“…Thus, it would have been more appropriate, as suggested by Schluger, 16 to restrict AMPLICOR testing only to patients with high and intermediate pretest probabilities. The incidence of PTB in this subgroup of patients was 23%, similar to the 21% reported by Catanzaro et al, 8 whose patients were selected by doctors experienced in the diagnosis of PTB. The cost saving would also be considerable since the AMPLICOR test costs about US$60 in the National University Hospital, Singapore, compared with less than US$5 for smear and culture.…”