BOSTON (EGMN) – Hyperchloremia in patients with Clostridium difficile infections is an indicator of disease severity and a risk factor for death within 30 days, according to Dr. Anilrudh A. Venugopal.
A retrospective chart review of 136 patients with C. difficile infections treated over an 8-month period showed that hyperchloremia was the only electrolyte abnormality associated with severe C. difficile infection, as determined by using two C. difficile infection scoring systems, Dr. Venugopal said at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
Among patients not on hemodialysis, hyperchloremia was also associated with an increased risk of all-cause mortality at 30 days, based on a multivariate analysis. Other significant predictors of death were mean albumin and creatinine levels, and the presence of malignant solid tumors.
“By identifying patients with Clostridium difficile infection that are at risk for severe disease, it may affect our initial management,” said Dr. Venugopal of the division of infectious disease at the St. John Hospital and Medical Center in Grosse Pointe Woods, Mich.
Because severe diarrheal disease can result in a metabolic acidosis that is often hyperchloremic and hypokalemic, he and his coinvestigators sought to evaluate whether electrolyte abnormalities at diagnosis could predict severe disease and death.
They retrospectively studied charts of 58 men and 78 women treated from October 2009 through May 2010. The mean patient age was 67 years. In all, 91% of the patients had been admitted to a health care facility within 30 days of the initial diarrheal episode, and 88% had received antibiotics within 39 days. The all-cause mortality rate was 23% (31 deaths).
The most common comorbidities were coronary artery disease/heart failure in 47%, diabetes in 37%, chronic obstructive pulmonary disease in 22%, and moderate to severe renal disease in 19% (26 patients, 12 of whom required dialysis).
In the initial univariate analysis, the authors sought to validate the scoring systems and found an association between death and a score of 2 or higher on each system, as well as a trend toward death and higher chloride levels.
To see whether conditions that cause electrolyte abnormalities, such as end-stage renal disease, could affect the association between chloride and mortality, the investigators evaluated lab results for the 12 patients on dialysis.
“What we found was that the dialysis patients had a significantly lower sodium and lower chloride level compared to the nondialysis population, and they had a higher potassium level,” Dr. Venugopal said at the conference, sponsored by the American Society for Microbiology.
The authors then removed the dialysis population and performed univariate analyses on 124 patients, which showed significant associations between death within 30 days and the mean chloride level (P = .04) and bicarbonate level (P = .05), but not the sodium or potassium levels. Other significant mortality risk factors in this group were agent change during therapy (P = .001), ICU stay prior to diagnosis (P = .006), solid tumor malignancies (P less than .0001), and HIV (P = .013).
In a univariate analysis stratified by scoring system, chloride alone among the electrolytes was significantly associated with a high severity score (P = .004 for the Belmares system; P less than .0001 for the Zar system).
In multivariate logistic regression analysis, again with only nondialysis patients, the authors found that the mean chloride level remained a significant predictor of 30-day mortality, with an odds ratio of 1.14 (P = .043). Other significant predictors in this model were solid tumors (OR, 14.08; P = .005), mean albumin level (OR, 0.91; P = .006), and mean creatinine level (OR, 2.12; P = .045). The study was internally funded. Neither Dr. Venugopal nor his coinvestigators said they had financial conflicts.
