Intra-abdominal infection and sepsis in immunocompromised intensive care unit patients: Disease expression, microbial aetiology, and clinical outcomes

We compared epidemiology of intra-abdominal infection (IAI) between immunocompromised and non-immunocompromised ICU patients and identified risk factors for mortality. We performed a secondary analysis on the "AbSeS" database, a prospective, observational study with IAI patients from 309 ICUs in 42 countries. Immunocompromised status was defined as either neutropenia or prolonged corticosteroids use, chemotherapy or radiotherapy in the past year, bone marrow or solid organ transplantation, congenital immunodeficiency, or immunosuppressive drugs use. Mortality was defined as ICU mortality at any time or 28-day mortality for those discharged earlier. Associations with mortality were assessed by logistic regression. The cohort included 2589 patients of which 239 immunocompromised (9.2 %), most with secondary peritonitis. Among immunocompromised patients, biliary tract infections were less frequent, typhlitis more frequent, and IAIs were more frequently healthcare-associated or early-onset hospital-acquired compared with immunocompetent patients. No difference existed in grade of anatomical disruption, disease severity, organ failure, pathogens, and resistance patterns. Septic shock was significantly more frequent in the immunocompromised population. Mortality was similar in both groups (31.1% vs. 28.9 %; p = 0.468). Immunocompromise was not a risk factor for mortality (OR 0.98, 95 % CI 0.66-1.43). Independent risk factors for mortality among immunocompromised patients included septic shock at presentation (OR 6.64, 95 % CI 1.27-55.72), and unsuccessful source control with persistent inflammation (OR 5.48, 95 % CI 2.29-12.57). In immunocompromised ICU patients with IAI, short-term mortality was similar to immunocompetent patients, despite the former presented more frequently with septic shock, and septic shock and persistent inflammation after source control were independent risk factors for death.