Search

Karen Rokkedal Lausch,1 Mette Søgaard,2,3 Flemming Schønning Rosenvinge,4,5 Helle Krogh Johansen,6 Trine Boysen,7 Bent Løwe Røder,8 Klaus Leth Mortensen,1,9 Lene Nielsen,10 Lars Lemming,9 Bente Olesen,10 Christine Leitz,11 Lise Kristensen,9,12 Esad Dzajic,13 Lars Jørgen Østergaard,1 Henrik Carl Schønheyder,14,15 Maiken Cavling Arendrup6,16,17 1Department of Infectious Disease, Aarhus University Hospital, 8200 Aarhus, Denmark; 2Department of Cardiology, Aalborg University Hospital, 9000 Aalborg, Denmark; 3Aalborg Thrombosis Research Unit, Department of Clinical Medicine, Faculty of Health, Aalborg University, 9000 Aalborg, Denmark; 4Department of Clinical Microbiology, Odense University Hospital, 5000 Odence C, Denmark; 5Department of Clinical Microbiology, Lillebaelt Hospital, 5500 Middelfart, Denmark; 6Department of Clinical Microbiology, Rigshospitalet, 2100 Copenhagen, Denmark; 7Department of Clinical Microbiology, Hvidovre Hospital, 2650 Hvidovre, Denmark; 8Department of Clinical Microbiology, Hospital of Slagelse, Slagelse Sygehus, 4200 Slagelse, Denmark; 9Department of Clinical Microbiology, Aarhus University Hospital, 8200 Aarhus, Denmark; 10Department of Clinical Microbiology, Herlev and Gentofte Hospital, University of Copenhagen, 2730 Herlev, Denmark; 11Department of Clinical Microbiology, Viborg Regionshospital, 8800 Viborg, Denmark; 12Department of Clinical Microbiology, Herning Regionshospital, 7400 Herning, Denmark; 13Department of Clinical Microbiology, Sydvestjysk Sygehus, 6700 Esbjerg, Denmark; 14Department of Clinical Microbiology, Aalborg University Hospital, 9000 Aalborg, Denmark; 15Department of Clinical Medicine, University of Aalborg, 9000 Aalborg, Denmark; 16Unit of Mycology, Statens Serum Institute, 2300 København, Denmark; 17Department of Clinical Medicine, University of Copenhagen, 2200 Copenhagen, Denmark Background: In accordance with interna

Laura Krogh Jørgensen,1 Lars Skov Dalgaard,1 Lars Jørgen Østergaard,1 Nanna Skaarup Andersen,2 Mette Nørgaard,3 Trine Hyrup Mogensen1 1Department of Infectious Diseases, Aarhus University Hospital, Aarhus, 2Department of Clinical Microbiology, Odense University Hospital, Odense, 3Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark Background: Large health care databases are a valuable source of infectious disease epidemiology if diagnoses are valid. The aim of this study was to investigate the accuracy of the recorded diagnosis coding of herpes simplex encephalitis (HSE) in the Danish National Patient Registry (DNPR). Methods: The DNPR was used to identify all hospitalized patients, aged ≥15 years, with a first-time diagnosis of HSE according to the International Classification of Diseases, tenth revision (ICD-10), from 2004 to 2014. To validate the coding of HSE, we collected data from the Danish Microbiology Database, from departments of clinical microbiology, and from patient medical records. Cases were classified as confirmed, probable, or no evidence of HSE. We estimated the positive predictive value (PPV) of the HSE diagnosis coding stratified by diagnosis type, study period, and department type. Furthermore, we estimated the proportion of HSE cases coded with nonspecific ICD-10 codes of viral encephalitis and also the sensitivity of the HSE diagnosis coding. Results: We were able to validate 398 (94.3%) of the 422 HSE diagnoses identified via the DNPR. Hereof, 202 (50.8%) were classified as confirmed cases and 29 (7.3%) as probable cases providing an overall PPV of 58.0% (95% confidence interval [CI]: 53.0–62.9). For “Encephalitis due to herpes simplex virus” (ICD-10 code B00.4), the PPV was 56.6% (95% CI: 51.1–62.0). Similarly, the PPV for “Meningoencephalitis due to herpes simplex virus” (ICD-10 code B00.4A) was 56.8% (