Innate Immune Response Monitoring Via Monocyte HLA-DR in Severe Intra-abdominal Infections at Risk of Fungal Infection

Evaluation of the Innate Immune Response Through Monocyte HLA-DR Monitoring During Severe Intra-abdominal Candidiasis in the Critically Ill Patients

Intra-abdominal candidiasis (IAC) is a frequent and severe fungal infection in critically ill patients, often diagnosed late. Its pathophysiology remains unclear, particularly regarding why some patients develop invasive infection while others only show benign colonization. A potential explanation lies in the state of innate immunity. Monocyte HLA-DR expression, a recognized marker of immune suppression in critical care, may be transiently but profoundly reduced in non-immunocompromised patients who go on to develop IAC. This observational study aims to evaluate whether patients with IAC have greater innate immune dysfunction-assessed by HLA-DR expression-compared to those with severe bacterial intra-abdominal infections. The goal is to better understand the immune mechanisms involved and improve early risk stratification for IAC.

Inclusion Criteria:

• Adult patient (≥ 18 years old)

• Patient admitted to the ICU or intermediate care unit for a severe intra-abdominal infection requiring urgent abdominal surgery

• Presence of at least one risk factor for intra-abdominal candidiasis:

  • Abdominal surgery within the last 7 days
  • Supramesocolic gastrointestinal perforation
  • Healthcare-associated intra-abdominal infection
  • Community-acquired intra-abdominal infection in an immunocompromised patient*
  • Intra-abdominal infection complicated by septic shock
  • Broad-spectrum antibiotic exposure within 72 hours prior to surgery

• And/or a Peritonitis Score ≥ 3 out of 4

• Patient affiliated with or benefiting from a national health insurance system

• Patient who has received full information about the clinical study

Exclusion Criteria:

• Radiologically guided drainage without surgery
• Infected acute pancreatitis
• Limitation or withdrawal of life-sustaining treatments
• Moribund patient with an expected life expectancy < 48 hours
• Woman of childbearing potential without effective contraception
• Refusal to participate in the study