Economic evaluation of the use of PCR assay in diagnosing pulmonary TB in a low-incidence area

Abstract

Economic evaluation of the use of PCR assay in diagnosing pulmonary TB in a low-incidence area. I. Rajalahti, E-L. Ruokonen, T. Kotomäki, H. Sintonen, M.M. Nieminen. #ERS Journals Ltd 2004. ABSTRACT: To determine whether polymerase chain reaction (PCR) testing in the initial diagnosis of pulmonary tuberculosis (TB) is cost-effective in a low-prevalence population, an economic evaluation was carried out between the smear and culture (NOPCR) and smear, culture and PCR (zPCR) strategies.A decision tree model based on retrospective laboratory data was developed to assess the strategies of testing patients with suspicion of TB. Direct healthcare costs prior to confirmation of TB or nontuberculous mycobacteria by PCR or culture were included. Effectiveness was measured by the probability of correct treatment and isolation decisions.In the baseline situation NOPCR costs J29.50 less than the zPCR strategy per patient tested. According to sensitivity analyses, reducing PCR test price, shortening test performance time or increasing the proportion of smear-positive patients in the tested population would contribute to cost savings with the zPCR strategy.Routine polymerase chain reaction testing of all specimens from suspected tuberculosis patients in a low-prevalence population was not cost-saving. When the polymerase chain reaction assay was applied only to smear-positive sputum specimens, the smear and culture strategy was clearly dominated by it, i.e. the polymerase chain reaction smear-positive sputum strategy was less costly and more effective in producing correct treatment decisions and isolations. To date the global tuberculosis (TB) epidemic has shown no notable decline. In low-prevalence countries, factors contributing to the spread of the disease, especially in hospital settings, are delays in diagnosis and initiation of treatment [1]. In addition to lack of suspicion of TB, diagnosis is prolonged by the time-consuming identification of the Mycobacterium tuberculosis complex in sputum specimens [2]. The acid-fast smear rapidly identifies patients with infectious TB, but is neither sensitive nor specific for M. tuberculosis bacteria. In countries like Finland (494 TB cases and 505 cases with nontuberculous mycobacteria in 2001) where nontuberculous mycobacteria are frequently detected, smear-positive nontuberculous cases may be isolated and treated with inappropriate drug combinations unnecessarily until culture results are available. Culture is sensitive in detecting mycobacteria for species identification and susceptibility testing, but requires a mean time of 2-3 weeks [3]. In smear-negative TB cases this may lead to unnecessary diagnostic procedures that increase healthcare costs and cause distress to the patients.Commercial nucleic acid amplification (NAA) assays are rapid, sensitive and specific tools for the detection of the M. tuberculosis complex in sputum specimens [4][5][6]. In addition to rapid differentiation between this complex and nontuberculous mycobacteria in smear-positive sputum specimens, NAA ...

Shortening Isolation of Patients With Suspected Tuberculosis by Using Polymerase Chain Reaction Analysis: A Nationwide Cross-sectional Study

“…A conventional PCR result will most often be available within 2 days; thus, the benefit of allowing discontinuation of isolation on the basis of single-sputum PCR results is a reduction of the time spent in isolation for patients who do not have contagious tuberculosis. Previously, PCR-based isolation decision models with fast-access PCR (Xpert RIF/MTB) were found cost-effective [21,27,28]. One study using a conventional PCR technique (Cobas Amplicor; Roche Diagnostics) [29] did not find this cost-effectiveness, mainly because PCR was performed only twice weekly and on all samples.…”

Costs of tuberculosis disease in the European Union: a systematic analysis and cost calculation

“…Recalculated from the detailed unit costs given for 2000, the mean costs for a 6-month treatment, which comprised of inpatient stays of only 14 days, amounted to J6673.10 per drug-susceptible TB case [40].…”

“…In the selection process 4278 citations and 241 websites were identified, of which only 12 scientific articles [35][36][37][38][39][40][41][42][43][44][45][46] and two websites [47,48] were eligible for final inclusion, as they contained specific information on at least one of the cost components as listed above. To take into consideration the gaps in gross domestic product (GDP) per capita between the 27 present EU member countries, we presented separately the results for the EU-15 states (member countries of the EU prior to the accession of 12 candidate countries on May 1, 2004 comprising the following 15 countries: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal, Spain, Sweden and the UK) and the other 12 countries that have since joined (table 1 shows figures of total treatment costs and table 2 shows the key features of all 12 studies included in our review).…”

Feasibility of Shortening Respiratory Isolation with a Single Sputum Nucleic Acid Amplification Test

“…Our data represent the experience of a single institution with a moderate annual prevalence of TB cases. Previous cost-effectiveness analyses have shown that routine use of NAA tests is more cost-effective in settings with high prevalence of TB and smearpositive cases (23,24), but performance in lower prevalence areas should still benefit from reducing hospitalization costs. The use of two different NAA tests in our study can be considered as another limiting factor of our study.…”