This study aims to evaluate the prognostic significance of CLI in predicting 28-day mortality and other outcomes in critically ill patients who develop post-operative abdominal sepsis.

Inclusion Criteria:

Age ≥ 18 years.

Postoperative secondary peritonitis requiring ICU admission, with clinical evidence of:

Diffuse or localized abdominal pain/tenderness. Peritoneal signs (e.g., guarding, rigidity, rebound tenderness). Imaging or intraoperative confirmation of purulent/exudative intra-abdominal fluid.

Systemic inflammation (e.g., fever, leukocytosis, or vasopressor requirement). Sepsis diagnosis per Sepsis-3 criteria: Suspected/confirmed infection with acute increase in SOFA score ≥2 points (6).

Anticipated ICU stay ≥48 hours postoperatively.

Exclusion Criteria:

• Pregnancy

  • Advanced liver disease (Child-Pugh class B or C) that might independently affect albumin levels
  • Advanced kidney disease (CKD stage 4 or 5) or patients on chronic dialysis
  • Expected mortality within 48 hours of ICU admission
  • Patients with primary peritonitis or tertiary peritonitis
  • Immunocompromised patients (e.g., on chronic immunosuppressive therapy, solid organ transplant recipients, patients with HIV and CD4 count <200/mm³)
  • Patients with pre-existing systemic inflammatory diseases that might affect baseline CRP levels
  • Patients participating in interventional trials that might affect outcomes

adult patients admitted to the ICU with post-operative secondary peritonitis requiring an ICU stay of at least 48 hours will be enrolled.