Candida as a risk factor for mortality in peritonitis

Objective: The clinical significance of Candida cultured from peritoneal fluid specimens remains a matter of debate. None of the studies that have addressed this issue have clearly distinguished between community-acquired peritonitis and nosocomial peritonitis. The current study tried to differentiate the pathogenic role of Candida in these two clinical settings and assess its importance on outcome. Design: A multiple-center, retrospective, case-control study was conducted in intensive care unit patients. The interaction between mortality rates and type of patients was assessed. In the case of a significant interaction, a separate analysis of mortality and morbidity was planned. Setting. Seventeen intensive care units in teaching and non-teaching hospitals. Patients: Cases were patients operated on for peritonitis with Candida cultured from the peritoneal fluid, whereas controls were operated patients free from yeast. Cases and controls were matched for type of infection, Simplified Acute Physiology Score II, age, and time period of hospitalization. Interventions: None. Measurements and Main Results: The following characteristics were collected: demographic variables, underlying disease, severity score, site of infection, microbiological features, and anti-infective treatments. Survival was defined as the main outcome criterion and morbidity variables as secondary criteria. Odds ratios of mortality were calculated. Matching was achieved in 91 cases and 168 controls. Matching criteria, clinical characteristics, and mortality rate were not statistically different between cases and controls. A significant interaction was demonstrated between mortality rates and type of infection, leading to separate analysis of patients with community-acquired peritonitis and nosocomial peritonitis. The subgroup analysis demonstrated an increased mortality rate only in nosocomial peritonitis with fungal isolates (48% vs. 28% in controls, p <.01). Upper gastrointestinal tract site (odds ratio, 4.9; 95% confidence interval, 1.6-14.8) and isolation of Candida species (odds ratio, 3.0; 95% confidence interval, 1.3-6.7, p <.001) were found to be independent risk factors of mortality in nosocomial peritonitis patients. Conclusions. Isolation of Candida species appears to be an independent risk factor of mortality in nosocomial peritonitis but not in community-acquired peritonitis.