Sepsis-induced immunosuppression (SIS) is a common complication in patients with septic shock. Reduced expression of Human leukocyte antigen isotype DR (HLA-DR) on circulating monocytes is a marker for SIS and correlates with risk of secondary infections and mortality. The miRSep study aims to improve the understanding of early microRNA (miRNA) mediated changes in HLA-DR on monocytes in patients with septic shock.

Inclusion Criteria:

Septic shock:

• New onset (<24h) of septic shock diagnosis according to Sepsis-3 definition
• (suspected) infection
• Vasopressors required to maintain mean arterial pressure ≥65mm Hg (despite adequate fluid resuscitation)
• Serum lactate level > 2mmol/L
• Minimum age of 18 years
• Expected length of stay >48h
• Written consent from an independent physician

Critically ill:

• Patients on mechanical ventilation (MV) in the ICU without an admission diagnosis of sepsis/septic shock according to Sepsis-3 definition
• Minimum age of 18 years
• Expected length of stay >48h
• Written consent from an independent physician

Exclusion Criteria:

• Age < 18 years

• Patients known not to speak German or French

• Patients with known.

  1. Pre-existing congenital or acquired severe immune deficiency (e.g. severe combined immunodeficiency, HIV infection, AIDS) or
  2. current immunosuppressive therapy (immunosuppressive biologicals or active lymphocyte therapy e.g. endoxan, rituximab or corticosteroid use at a dose > 10 mg/day equivalent of prednisone. However, acute corticosteroid treatment of a relative adrenal insufficiency using a maximum hydrocortisone dose of 200 mg/day is accepted.

Patients receiving treatment in the ICU department of the University Hospital Bern, CH.