Characteristics, risk factors and outcomes of critically ill patients with active TB

BACKGROUND: TB continues to impose a significant healthcare burden despite advancement in diagnostics and increased availability of effective antimicrobials. Recent years have seen a resurgence of the disease in association with increasing life expectancy and use of immunosuppressive therapy. Mortality remains high in TB patients requiring admission to critical care units.

METHODS: We conducted a retrospective study in two public hospitals to determine factors associated with mortality in patients with TB requiring critical care admission. All patients aged ≥21 years with a diagnosis of active TB involving any organ system at the time of a critical care admission were eligible. The primary outcome measure was 30-day mortality.

RESULTS: Over the study period of 4 years, 148 patients were identified. Overall 30-day mortality was 36.5%. Based on multivariate analysis, factors which independently correlated with 30-day mortality include higher APACHE II (Acute Physiology and Chronic Health Evaluation II) score, acid-fast bacilli smear positivity, initiation of anti-TB treatment prior to critical care admission and need for renal replacement therapy.

CONCLUSION: TB in critically ill patients continues to be associated with significant mortality. The factors identified to be associated with poor survival outcomes in our study were largely related to greater disease burden and potential for suboptimal treatment.