Procalcitonin Aided Antimicrobial Therapy vs Standard of Care

After the randomization, PCT plasma concentration will be dosed and repeated every 24 hours and antimicrobial treatment will be withdrawn as soon as the PCT value will decrease \> 80% of peak value or will fall below 0.25 ng/mL. Patients with a normal baseline PCT value (below 0.25 ng/mL) will start the antimicrobial therapy, as clinically appropriate and PCT plasma concentration will be repeated every 24 hours, as indicated in the protocol. The antimicrobial agents will be managed according to the clinical and radiological evolution of the LRTI.

Patients assigned to the control group will be treated according to the best standard of care and PCT will not be evaluated for the whole duration of the study.