Serum procalcitonin in pulmonary tuberculosis

To evaluate the level and prognostic value of procalcitonin (PCT) in a West African out-patient cohort with pulmonary tuberculosis (PTB).

Patients were clinically scored (TB score), grouped into severity classes (SCs) upon diagnosis and followed for 12 months. Patients were categorised by comparisons of severity class (SC I+II or SC III) and levels of PCT and C-reactive protein (CRP) at diagnosis. Fifty healthy volunteers from the study area were used as controls. The association with TB score was explored using Spearman's rank correlation test. Survival curves stratified after baseline levels of PCT and CRP were compared using the log-rank test.

We included 218 patients in the study. PCT and CRP levels were low, but were significantly higher in patients than in controls (P < 0.001), and were higher for SC III compared to SC I+II patients (P = 0.021 for PCT, P < 0.001 for CRP). Human immunodeficiency virus (HIV) status did not influence results. We found positive correlations between both PCT and CRP and TB score. There was a significantly increased risk of mortality with increasing baseline PCT (P = 0.01), whereas high CRP did not predict mortality rate (P = 0.887).

In West African PTB patients, PCT levels were low but increased significantly with increasing severity of disease, and can predict mortality risk.