[The diagnostic value of procalcitonin in severe sepsis]

Sepsis and its complications are the most common cause of the death in the intensive care unit. In spite of the treatment mortality remains up to 28-50%, and 60-90% of the patients are lost because of the complications of sepsis. So it is very important to diagnose this pathology and start the treatment early. The diagnosis of sepsis is complicated for clinical signs and symptoms are not specific and manifest in the patients who have non-infective diseases, when systemic inflammatory response is involved. Parameters of systemic inflammatory response, such as body temperature, heart rate, respiratory rate, leukocyte count, and C-reactive protein concentration, used in clinical practice are neither specific, non sensitive. These parameters often provide information that is inadequate for the discrimination of bacterial and nonbacterial infections and for diagnosis. So it is impossible to differentiate systemic inflammatory response and sepsis. Procalcitonin is a new parameter for diagnosis of bacterial, fungal and parasitical infections. In healthy humans almost all procalcitonin, which is produced in thyroid gland, is resolved and does not reach the blood stream. Its half-life in plasma is only few minutes, so in healthy humans the level of procalcitonin is very low (<0.1 ng/ml) and is not detectable by standard methods. In the case of infection the level of procalcitonin rapidly increases during 2-6 hours and reaches the maximum level after 6-12 hours. The measurement of procalcitonin levels can be used for instant diagnosis as well as for evaluation of the treatment effectiveness. In our article we review the new literature data on the importance of procalcitonin level for sepsis diagnosis in comparison with other parameters of systemic inflammatory reaction, and discuss the indications for procalcitonin analysis.