The study aims to compare the efficacy and safety of an absolute procalcitonin (PCT) value-guided antibiotic initiation protocol and a protocol using the kinetics of PCT (the difference between the actual and the previous day value) in hemodynamically stable critically ill patients with suspected new-onset infection on admission or during ICU stay.
The main question it aims to answer:
* Can the investigators decrease the number of unnecessary AB therapies using the kinetics of PCT insted of using absolute PCT values? * Is it safe to use PCT kinetics together with the clinical picture to guide AB initiation? AB therapy will be initiated according to predefined PCT protocols (Kinetics and Absolute Group). After 72 hours of treatment, an independent multidisciplinary team (infectologist, microbiologist and intensivist) will decide about the necessity of the treatment with all the relevant results in hand.
Adult (18 years < ) non-surgical, surgical, or trauma patients
Suspected new-onset infection on admission or during ICU stay
The source of infection is known or highly suspected, and source control has been implemented if needed (i.e., removal of an infected device (e.g., central line, endoprosthesis)
Two PCT values are available - one on the day of suspicion of infection and one 24±4 hours earlier.
Septic shock (hypotension requiring vasopressor therapy to maintain mean blood pressure of 65 mmHg or greater and having a serum lactate level greater than 2 mmol/L after adequate fluid resuscitation)
Infections for which long-term antibiotic treatment is strongly recommended (e.g., infective endocarditis, osteoarticular infections, chronic prostatitis, tuberculosis)
Infections related to primary surgical intervention and adequate source control cannot be guaranteed (e.g., fecal peritonitis, pancreatic necrosectomy, infective necrotizing fascitis - i.e., Fournier's gangrene),
Indisputable infections (e.g., hepatic abscess, empyema)