OBJECTIVES: To estimate the incremental cost-effectiveness ratio of Interferon Gamma Release Assay (IGRA) for the diagnosis of latent tuberculosis infection (LTBI) in patients with renal failure undergoing hemodialysis, compared to tuberculin skin test (TST) in the Brazilian Private Healthcare System (PHS).

METHODS: A decision tree model was developed based on the test performed and probability of TB activation. The direct medical costs of each test, treatment of adverse events of secondary chemoprophylaxis and treatment of TB complications were included, under the perspective of PHS. Since the treatment of LTBI and active TB are covered by Brazilian Public Healthcare System, these costs were not considered. The outcome considered was prevented cases of active TB. Costs are represented as Brazilian currency (BRL)Outcomes considered were prevented cases of active TB. Sensitivity analyses were performed to explore uncertainties.

RESULTS: IGRA dominates TST in this population. From a simulation of a cohort of 1000 patients with renal failure undergoing hemodialysis, it was estimated that the evaluation of ILTB with IGRA test is associated with 8 incremental cases of active TB avoided. The clinical benefit is accompanied by a decrease in the average cost per patient (-BRL 67,888). This lower cost is mainly related to the high cost for treating TB complications.

CONCLUSIONS: Today, the standard test for LTBI detection is the TST. However, TST presents impaired accuracy in immunocompromised patients and alternatives are necessary for these patients. The use of IGRA for LTBI detection in patients with renal failure undergoing hemodialysis is related to a greater capacity of avoiding TB active cases and consequent lower cost per patient.