Disseminated intravascular coagulation diagnosis: Positive predictive value of the ISTH score in a Danish population

BACKGROUND: The diagnostic accuracy of the ISTH’s disseminated intravascular coagulation (DIC) score remains to be investigated in contemporary patient populations. OBJECTIVE: To examine the positive predictive value (PPV) of an ISTH DIC score ≥5 for identifying patients with overt DIC in a Danish hospital laboratory information system database. MATERIALS AND METHODS: A population‐based cross‐sectional validation study in the Central Denmark Region (2015‐2018). Patients with a DIC score ≥5 were identified from the hospital laboratory information system database. Only patients with a potential underlying cause of DIC were included in the analyses. Cases were adjudicated by the authors as the gold standard for DIC diagnosis. The diagnosis of overt DIC was assigned on the basis of clinical signs of microthrombosis and/or bleeding and available laboratory records. PPVs with 95% confidence intervals (CIs) were computed. RESULTS: Medical records of 225 patients were included. The overall PPV for overt DIC was 68% (95% CI, 61‐74) and for overt + subclinical DIC, 83% (95% CI, 77%‐88%) and increased with higher scores from 47% (95% CI, 35‐59) for DIC score 5 to 88 (95% CI, 79‐94) for DIC score ≥7. PPV was higher among intensive care patients and patient with sepsis, low antithrombin activity, prolonged activated partial thromboplastin time, or high Sequential Organ Failure Assessment score. CONCLUSION: The accuracy of ISTH DIC score ≥5 was moderate for overt DIC but increased with increasing scores and depended on the underlying cause of DIC. This new knowledge provides guidance to physicians and enables DIC research using laboratory‐based data.