Please select the eligibility criteria that correspond to the clinical trial below.
Title: Stop Antibiotics on Procalcitonin Guidance Study
Brief Summary: This is a randomized controlled trial comparing standard-of-care therapy of infections in critically ill patients with a procalcitonin-guided approach evaluating efficacy (antibiotics consumption) and safety (mortality).


Options:
A: Inclusion Criteria:

* Severe sepsis or septic shock according to ACCP/SCCM criteria
* Onset of severe sepsis or septic shock \<24 h
* Age \>= 18 years
* Informed consent

Exclusion Criteria:

* Pregnant or breast-feeding women
* Fertile female women without effective contraception
* Participation in interventional clinical trial within the last 30 days
* Current participation in any study
* Former participation in this trial
* Selenium intoxication
* No commitment to full patient support (i.e. DNR order)
* Patient's death is considered imminent due to coexisting disease
* Relationship of the patient to study team member (i.e. colleague, relative)
* Infection where guidelines recommend a longer duration of antimicrobial therapy (i.e. endocarditis, tuberculosis, malaria etc)
* Immunocompromised patients
B: Inclusion Criteria:

1. Patients with clinically suspected or microbiologically confirmed bacterial sepsis
2. Informed consent

Exclusion Criteria:

1. Patients with microbiologically documented infections caused by the following microorganisms: Listeria spp, Legionella pneumophilia, Mycobacterium tuberculosis, Staphylococcus aureus
2. Patients with fungal infections
3. Patients with severe infections due to viruses or parasites (e.g. hemorrhagic fever, malaria)
4. Patients with suspected or confirmed bacterial meningitis or endocarditis
5. Patients with localized, deep-seated abscesses (e.g. brain abscess) without systemic sepsis
6. Patients with chronic, localized infections (e.g. chronic osteomyelitis) without systemic sepsis
7. Neutropenic and other severely immuno-compromised patients (patients infected with human immunodeficiency virus and a CD4 count \< 200; patients on immuno-suppressive therapy after solid organ transplantation; patients with cystic fibrosis)
8. Withholding of life-support
9. Early discharge or death (\< 24 hours after admission)
10. Complete absence of antimicrobial treatment despite suspicion of sepsis
C: Inclusion Criteria:

* Age over 18 years old
* receiving antibiotics for no more than 24 hours for an assumed or proven infection
* Informed consent

Exclusion Criteria:

* Failure to obtain written consent to participate
* Patients receiving prolonged antibiotic therapies (\> 3 weeks, e.g. endocarditis, cerebral/hepatic abscess)
* Patients with severe infections due to viruses or parasites (e.g. Dengue, Toxoplasma gondii, Plasmodium spp.)
* Patients infected with Mycobacterium tuberculosis
* Patients entering the ICU for post-operative observation and/or on antibiotic prophylaxis with an estimated length of stay less then 24 hrs.
* Patients suffering from cystic fibrosis
* Severely immunocompromised patients such as patients with HIV and with a CD4 count of less than 200 cells/mm, neutropenic patients (\<500 neutrophils per mL) or patients with solid organ transplantation
* Moribund patients
D: Inclusion Criteria:

* Patient hospitalised in the ICU
* Bacterial infection suspected
* At ICU admission the patient do not receive antibiotics or receive antibiotics for less than 24hours and an interval between admission and inclusion \< 12 hours
* During ICU stay, provided that the interval between the start of suspected infection and inclusion is \< 12hours
* Written inform consent from the patient or relatives. The consent may be obtained after the enrollment if the patient is not able to give consent and if there is no relatives

Exclusion Criteria:

* Age \< 18 years
* Pregnancy
* Patient expected to remain hospitalised in the ICU for less than 3 days
* Neutropenia
* Infection or presumed infection requiring prolonged antibiotic therapy (endocarditis,osteo-articular infection, mediastinitis, deep abscess, tuberculosis, pneumocystis pneumonia, toxoplasmosis).
* Simplified Acute Physiology Score II at ICU admission (calculated during the first 12h)
* Attending physician declining to use full life support.

Answer: C