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

Central Hospital, Nancy, France100 enrolled

Overview

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.

Study Type

OBSERVATIONAL

Enrollment

100

Conditions

Intra-abdominal Infection Critical Illness Post-Op Infection Immunization; Sepsis Candida Sepsis

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Correlation Between percentage of Monocyte HLA-DR Expression and the Occurrence of Intra-abdominal Candidiasis

Assessment of the relationship between monocyte HLA-DR expression levels and the development of intra-abdominal candidiasis in critically ill patients with severe intra-abdominal infection.

Time frame: Within 7 days after abdominal surgery

Secondary Outcomes

Change Over Time in Percentage of Monocytes Expressing HLA-DR Measured by Flow Cytometry in Patients With vs Without Intra-abdominal Candidiasis

Peripheral venous blood will be collected at Day 0 (within 6 hours after index surgery), Day 3, Day 5, and Day 7 post-surgery. Monocyte HLA-DR expression will be quantified as the percentage of CD14+/CD16-/low monocytes positive for HLA-DR using standardized flow cytometry with anti-HLA-DR monoclonal antibody. Results will be compared between patients with confirmed intra-abdominal candidiasis (peritoneal culture positive for Candida) and those with intra-abdominal infection without fungal involvement. Primary analysis: between-group difference in change from baseline (Day 0) to Day 7 in percentage of HLA-DR+ monocytes

Time frame: From Day 0 (surgery) to Day 7 post-surgery

Variation in Lymphocyte Subpopulations Based on Presence or Absence of Intra-abdominal Candidiasis

Analysis of the changes in lymphocyte subpopulations counts (CD4+ T cells, CD8+ T cells, NK cells, B cells) in patients with versus without intra-abdominal candidiasis

Time frame: From Day 0 (surgery) to Day 7 post-surgery

Impact of Immune Dysfunction on In-Hospital Mortality

Evaluation of the correlation between low HLA-DR expression and in-hospital mortality

Time frame: From surgery to Day 28

Impact of Immune Dysfunction on Source Control of Infection

Assessment of whether immune dysfunction (defined by a low expression level of HLA-DR) is associated with failure or delay in achieving effective surgical or medical source control of the intra-abdominal infection

Time frame: Up to 28 days