Use of International Classification of Diseases, Ninth Revision Clinical Modification Codes and Medication Use Data to Identify Nosocomial Clostridium difficile Infection
- 1 November 2009
- journal article
- research article
- Published by Cambridge University Press (CUP) in Infection Control & Hospital Epidemiology
- Vol. 30 (11), 1070-1076
- https://doi.org/10.1086/606164
Abstract
Objective.: The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code for Clostridium difficile infection (CDI) is used for surveillance of CDI. However, the ICD-9-CM code alone cannot separate nosocomial cases from cases acquired outside the institution. The purpose of this study was to determine whether combining the ICD-9-CM code with medication treatment data for CDI in hospitalized patients could enable us to distinguish between patients with nosocomial CDI and patients who were admitted with CDI. The primary objective was to compare the sensitivity, specificity, and predictive value of using the combination of ICD-9-CM code for CDI and CDI treatment records to identify cases of nosocomial CDI with the sensitivity, specificity, and predictive value of using the ICD-9-CM code alone.Design.: Validation sample cross-sectional study.Setting.: Academic health center.Methods.: Administrative claims data from July 1, 2004, to June 30, 2005, were queried to identify adults discharged with an ICD-9-CM code for CDI and to find documentation of CDI therapy with oral vancomycin or metronidazole. Laboratory and medical records were queried to identify symptomatic CDI toxin-positive adult patients with nosocomial CDI and were compared with records of patients whose cases were predicted to be nosocomial by means of ICD-9-CM code and CDI therapy data.Results.: Of 23,920 adult patients discharged from the hospital, 62 had nosocomial CDI according to symptoms and toxin assay. The sensitivity of the ICD-9-CM code alone for identifying nosocomial CDI was 96.8%, the specificity was 99.6%, the positive predictive value was 40.8%, and the negative predictive value was 100%. When CDI drug therapy was included with the ICD-9-CM code, the sensitivity ranged from 58.1% to 85.5%, specificity was virtually unchanged, and the range in positive predictive value was 37.9%–80.0%.Conclusion.: Combining the ICD-9-CM code for CDI with drug therapy information increased the positive predictive value for nosocomial CDI but decreased the sensitivity.Keywords
This publication has 18 references indexed in Scilit:
- Increase in AdultClostridium difficile–related Hospitalizations and Case-Fatality Rate, United States, 2000–2005Emerging Infectious Diseases, 2008
- Treatment ofClostridium difficileInfectionClinical Infectious Diseases, 2008
- Clinical Recognition and Diagnosis ofClostridium difficileInfectionClinical Infectious Diseases, 2008
- The Emerging Infectious Challenge of Clostridium difficile-Associated Disease in Massachusetts Hospitals: Clinical and Economic ConsequencesInfection Control & Hospital Epidemiology, 2007
- Recommendations for Surveillance of Clostridium difficile–Associated DiseaseInfection Control & Hospital Epidemiology, 2007
- Clostridium difficile-Associated Disease in Oregon: Increasing Incidence and Hospital-Level Risk FactorsInfection Control & Hospital Epidemiology, 2007
- Accuracy of ICD-9 coding for Clostridium difficile infections: a retrospective cohortEpidemiology and Infection, 2006
- ICD-9 Codes and Surveillance for Clostridium difficile–associated DiseaseEmerging Infectious Diseases, 2006
- Increasing Risk of Relapse after Treatment of Clostridium difficile Colitis in Quebec, CanadaClinical Infectious Diseases, 2005
- Relatively Poor Outcome after Treatment of Clostridium difficile Colitis with MetronidazoleClinical Infectious Diseases, 2005