The value of procalcitonin change from the day before to the day when infection was suspected in predicting bacterial infection in intensive care patients.

Starting antibiotic therapy early in critically ill patients with suspected infection is of utmost importance with significant effect on survival. Procalcitonin is a reliable sepsis marker but results about its usefulness in initiating antimicrobials are conflicting. Our aim is to investigate the predictive value of 24 hours procalcitonin kinetics before starting empirical antibiotic therapy in intensive care patients as an indicator of the presence of bacterial infection.

Inclusion Criteria:

• Clinical signs of infection
• Suspected or proven acute infection requiring empiric antibiotic therapy as decided by the attending ICU physician
• Microbiological sample sent for staining
• Inflammatory markers available from the previous day

Exclusion Criteria:

• Patients younger than 18 years
• Who received prophylactic or empiric antibiotic therapy 48 hours before inclusion
• Whose receiving acute renal replacement therapy in the first 24 hours following antibiotic treatment
• Following cardiopulmonary resuscitation
• End stage diseases with a "do not resuscitate" order
• Immunocompromised patients (human immunodeficiency virus infection, bone marrow transplantation, malignant haematological disorders and chemotherapy)
• Post cardiac surgery patients

All patients with suspected infection during their stay on the intensive care unit were screened for eligibility. Patients were enrolled, when the attending intensive care specialist had a suspicion of infection and decided to start empirical antibiotic therapy and infalmmatory markers were available from the previous day.