Derivation and validation of a simple clinical bedside score (ATLAS) for Clostridium difficile infection which predicts response to therapy

Abstract

BackgroundClostridium difficile infection (CDI) continues to be a frequent and potentially severe infection. There is currently no validated clinical tool for use at the time of CDI diagnosis to categorize patients in order to predict response to therapy.MethodsSix clinical and laboratory variables, measured at the time of CDI diagnosis, were combined in order to assess their correlation with treatment response in a large CDI clinical trial database (derivation cohort). The final categorization scheme was chosen in order to maximize the number of categories (discrimination) while maintaining a high correlation with clinical cure assessed two days after the end of therapy. Validation of the derived scoring scheme was done on a second large CDI clinical trial database (validation cohort). A third comparison was done on the two pooled databases (pooled cohort).ResultsIn the derivation cohort, the best discrimination and correlation with cure was seen with a five-component ATLAS score (age, treatment with systemic antibiotics, leukocyte count, albumin and serum creatinine as a measure of renal function), which divided CDI patients into 11 groups (scores of 0 to 10 inclusive) and was highly correlated with treatment outcome (R2=0.95; P<0.001). This scheme showed excellent prediction of cure in the validation cohort (overall Kappa=95.2%; P<0.0001), as well as in the pooled cohort, regardless of treatment (fidaxomicin or vancomycin).ConclusionsA combination of five simple and commonly available clinical and laboratory variables measured at the time of CDI diagnosis, combined into a scoring system (ATLAS), are able to accurately predict treatment response to CDI therapy. The ATLAS scoring system may be useful in stratifying CDI patients so that appropriate therapies can be chosen to maximize cure rates, as well as for categorization of patients in CDI therapeutic studies in order allow comparisons of patient groups.

Diagnosis and Treatment ofClostridium difficilein Adults

“…High risk patients had a score ≥6 41 . Another scoring system study used age, treatment with systemic antibiotics, leukocyte count, albumin, serum creatinine to predict response to vancomycin or fidaxomicin 42 .…”

Derivation and validation of a simple, accurate and robust prediction rule for risk of mortality in patients with Clostridium difficile infection

“…Thus, an acute rise/decline in these markers, around the time of infection diagnosis may be generally attributed to C. difficile infection and a combination of all these variables would prove useful as predictors of mortality in patients with CDI and warrants their inclusion in a prediction rule, as supported by others [11,17-20]. …”

“…A recent publication has implicated that serum albumin, WCC and CRP are important prognostic variables for short term mortality in patients with CDI [17]. Other studies have found that a fall in serum albumin level was consistent with the onset of CDI [18] as well as being prognostic of mortality from CDI [11,17,19] and increased WCCs have also been implicated in other studies [11,19,20] as being prognostic of mortality in patients with CDI.…”

Efficacy of computed tomography for the prediction of colectomy and mortality in patients with clostridium difficile infection

“…Patients for whom a CT was performed had a mean Charlson comorbidity index of 2.09 (±2.4) and 33 out of 34 patients had previous antibiotic use (97.1%). The ATLAS [6] scoring system was used to evaluate disease severity; in the 34 patients, there was a mean score of 5.9 (range 1–9). Use of steroids or other immunosuppressants was observed in 12 subjects (35.3%).…”