Clinical suspicion as a primary guidance to use commercial amplification tests for rapid diagnosis of pulmonary tuberculosis

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 ].…”

“…The prevalence of PTB for the high pretest probability group was 67.4%, lower than that described in the literature where smear-positive and smear-negative PTB were included in analyses, the prevalence of PTB for intermediate pretest probabilities was 24%, similar to that (29%) described by Catanzaro, but higher than that described by Lim (3.4%). PTB prevalence for low pretest probability was 7.5%, higher than that cited elsewhere with low burdens of TB and HIV infection in health settings [ 24 - 26 ].…”

“…The clinical evaluation used in parallel with the PCR test may be an alternative to the use of the PCR test for rapid diagnosis of PTB, especially in a hospital setting with a high burden of TB/HIV co-infection. The combination of clinical judgment and amplification results strongly enhances a rapid and correct diagnosis of PTB [ 26 ].…”

Review of Nucleic Acid Amplification Tests and Clinical Prediction Rules for Diagnosis of Tuberculosis in Acute Care Facilities

“…The diagnostic performance of NAATs is influenced by the clinical suspicion of the healthcare provider regarding TB. Many studies conducted in low 56 , 57 and high TB burden 58 , 59 countries have demonstrated that sensitivity and specificity of NAATs is significantly lower among patients whose healthcare providers had a low clinical suspicion for TB compared with those patients with a high or moderate suspicion for TB. These differences in performance of NAATs by level of clinical suspicion have also been noted for patients with AFB smear-negative pulmonary TB 59 .…”