the impact of treatment on serum level of procalcitonin in patients with active pulmonary tuberculosis

introduction: about one third of the world&apos;s population is infected with tuberculosis (tb) and each year, about 1.5 to 2 million people die from tb. procalcitonin (pct) is an inflammatory marker that its level has variable materials and methods: this conducted on patients with pulmonary tb. data were collected using a check list. the serum level of pct was measured by elisa test at the beginning and after six months of treatment. all data were analyzed using spss 16.  results: there are some discussions in the utilization of pct as a diagnostic marker in active pulmonary tb. the aim of this study was to compare serum pct before and after treatment in patients with pulmonary tb. results: forty-two patients with active pulmonary tb entered in this study. the mean age of the patients was 45.48 ± 12.54 years and 54.8% of them were male. most of the patients (59.5 %) were rural inhabitants. there was a family history of tb in 26% of patients. the most common symptom (45.2%) was cough. mean pct prior to treatment was 1.25 ± 0.98 ng/ml. and 81% of the patients had pct higher than 0.5 to 5. after treatment pct level reduced significantly (p<0.001). the mean erythrocyte sedimentation rate (esr) and c-reactive protein (crp) before treatment were 45.88 ± 21.87 and 7.16 ± 3.98 respectively that were reduced significantly after treatment (p<0.001). neutrophil counts before treatment was 6221 ± 3161 cells per ml. and decreased statistically significant after treatment (p=0.01). conclusion: our results showed that the pct levels in pulmonary tb were high in active disease and reduced after treatment. pct level may be used for follow-up as a discriminative marker between active and cured pulmonary tb and predict treatment response, although the pct assay cannot be substituted for microbiological and pathological data.