Cost-effectiveness study of the microbiological diagnosis of tuberculosis using geneXpert MTB/RIF.

Introduction/objective: To perform a cost-effectiveness analysis of a molecular biology technique for the diagnosis of tuberculosis compared to the classical diagnostic alternative.

Methods: A cost-effectiveness analysis was performed to evaluate the theoretical implementation of a molecular biology method including two alternative techniques for early detection of Mycobacterium tuberculosis Complex, and resistance to rifampicin (alternative1: one determination in selected patients; alternative2: two determinations in all the patients). Both alternatives were compared with the usual procedure for microbiological diagnosis of tuberculosis (staining and microbiological culture), and was accomplished on 1,972 patients in the period in 2008-2012. The effectiveness was measured in QALYs, and the uncertainty was assessed by univariate, multivariate and probabilistic analysis of sensitivity.

Results: A value of €8,588/QALYs was obtained by the usual method. Total expenditure with the alternative1 was €8,487/QALYs, whereas with alternative2, the cost-effectiveness ratio amounted to €2,960/QALYs. Greater diagnostic efficiency was observed by applying the alternative2, reaching a 75% reduction in the number of days that a patient with tuberculosis remains without an adequate treatment, and a 70% reduction in the number of days that a patient without tuberculosis remains in hospital.

Conclusion: The implementation of a molecular microbiological technique in the diagnosis of tuberculosis is extremely cost-effective compared to the usual method. Its introduction into the routine diagnostic procedure could lead to an improvement in quality care for patients, given that it would avoid both unnecessary hospitalisations and treatments, and reflected in economic savings to the hospital.