The role of procalcitonin in febrile patients.

Sir, We read the article by Qu et al1 with great interest. The authors investigated the role of procalcitonin (PCT) in distinguishing bacterial infections in febrile patients. We believe that this topic can be enriched with the points listed below: Groups 1 and 2 represented bacterial infection groups which consisted of 161 hospital acquired infection cases (58%) and 115 community acquired infection cases (42%). If there are significant differences in the levels of PCT, C-reactive protein (CRP), interleukin-6 (IL-6) and serum amyloid A (SAA) between hospital acquired infection and community acquired infection cases, it can be useful in guiding antibiotic treatment. Bacterial pneumonia was the most common diagnosis in their study, but Streptococcus pneumoniae which is the most common aetiological agent of pneumonia, was not isolated in any of their febrile patients. This point should be clarified. The PCT level of some patients in the bacterial infection group was below the cut-off level. It is important to know which infections and bacteria cause low PCT levels. Mortality among patients was not mentioned. It would be important to know whether there was a significant difference in PCT levels between survivors and non-survivors. Finally, we think that the aforementioned data will be helpful to increase the significance of PCT especially in emergency department and intensive care unit.