Please select the eligibility criteria that correspond to the clinical trial below.
Title: Procalcitonin-Guided Antimicrobial Discontinuation Strategy in Critically Ill Patients With Suspected or Confirmed Bacterial Sepsis
Brief Summary: The current study aims to validate the diagnostic use of PCT assessing its capability to individualize and shorten the duration of antibiotic therapy in critically ill patients with suspected or confirmed sepsis.

In particular, no well-designed intervention study has properly examined the following hypothesis: A PCT-guided antibiotic discontinuation strategy enables to reduce antibiotic treatment duration in critically ill patients with suspected or documented sepsis, without harming patient safety.


Options:
A: 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
B: 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.
C: Inclusion Criteria:

* suspected lower respiratory tract infection
* must be able to give consent

Exclusion Criteria:

* age under 18 years
* not able to give consent
* admitted not primarily because of the respiratory tract infection
* hospital acquired infections
D: 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.

Answer: A