Please select the eligibility criteria that correspond to the clinical trial below.
Title: Impact of Procalcitonin to Reduce Antibiotics Use in ICU Adults Patients
Brief Summary: The study is a prospective, randomized, controlled intervention trial conducted in 9 centers, comparing a conventional strategy versus a PCT-guided strategy to start or to discontinue antibiotics, in patients with suspected community or hospital- acquired infection.


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:

* age \> 17 years
* patients in intensive care unit
* signed informed consent
* suspected or confirmed severe sepsis or septic shock

Exclusion Criteria:

* Infections caused by Listeria spp, Legionella pneumophilia, Mycobacterium tuberculosis
* Bacteremia due S. aureus
* Infections requiring prolonged therapies, such as endocarditis, cerebral abscess, chronic osteomyelitis
* Suspected or confirmed infection caused by virus, parasites
* Infections caused by P. aeruginosa ou A. baumannii
* Severe immunosuppression (ex: AIDS, post bone-marrow transplant,cystic fibrosis)
* Traumatism latest five days
* Surgery latest 5 days
* Carcinoid tumor, lung cancer, medullary thyroid cancer
C: Inclusion Criteria:

Fulfilment of all of the following three criteria:

1. Male or female, aged \> 18 years of age.
2. Admitted to the participating Intensive Care Units (ICUs) at the following hospitals: Hvidovre Hospital, Bispebjerg Hospital, Amager Hospital, Herlev Hospital, Glostrup Hospital, and Gentofte Hospital
3. Ability to understand and provide written informed consent to participate in this trial; or ability to understand and provide oral informed consent in the presence of at least one impartial witness who should sign and personally date the consent form; or the subject's legally acceptable representative can understand and provide written informed consent if the subject is not capable of this because of the present mental or physical condition of the subject.

Exclusion Criteria:

A subject will NOT be eligible for inclusion in this trial if any of the following criteria apply:

1. Subjects with known hyperbilirubinaemia (\> 0.4 mg/ml) or hypertriglyceridaemia (\> 10 g/l) since this can interfere with measurements. If subjects with unknown status on these points are included and have PCT measurements, the measuring equipment will detect these conditions.
2. Subjects suffering from a blood disorder, where daily sampling of 7 ml of blood for a maximum of 28 days (210 ml distributed on 28 days) will be an inconvenience or a potential risk, which could compromise the safety of the subject.
3. Subjects who are pregnant or breast feeding

The a priori probability of surviving with the normal recommended diagnostics and treatment with the presently available means to detect infections and, on the other hand, the normal diagnostics and treatment together with daily procalcitonin measurements and prompt clinical reaction should be equal.
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: D