Empiric vs screening-based use of isoniazid for tuberculosis prophylaxis: Safety and effectiveness in lung transplant recipients in Saudi Arabia.

Background: Tuberculosis (TB) is a major complication following transplantation. The likelihood of TB may be increased in transplant patients living in TB-endemic areas such as Saudi Arabia. In areas where TB is less common, guidelines recommend isoniazid (INH) for TB prophylaxis depending on patient and donor screening results. However, in TB-endemic regions, studies have supported its use in all transplant patients regardless of TB screening results. This study aimed to compare the safety and effectiveness of administering INH prophylaxis therapy based on the TB screening results of lung transplant (LT) recipients.

Methods: We conducted a single-center retrospective cohort study on LT recipients. The outcomes were compared between patients who were administered screening-based prophylaxis (SBP) with INH based on their tuberculin skin tests (TSTs) or QuantiFERON results and those who were administered empirical prophylaxis (EP) with INH regardless of TB screening results. The primary endpoint was the incidence of TB infection, and the secondary endpoints were INH-induced hepatotoxicity and INH resistance.

Results: A total of 50 patients received SBP and 30 received EP. TB incidences were 8% and 0%, respectively (P = .0487). One of these patients had INH resistance, and one patient experienced INH-induced hepatotoxicity (P = .1591); both were in the SBP group.

Conclusion: The low rates of TB infection, INH-induced hepatotoxicity, and INH resistance in the EP group suggest that INH prophylaxis appears to prevent TB and can be safely used in all LT recipients. However, prospective studies using large sample sizes are required to confirm these findings.