Age adjusted cut-off using the IL D-dimer HS assay to exclude pulmonary embolism in patients presenting to Emergency.
Intern Med J. 2018 Jun 05;:
Authors: Lim MS, Bennett A, Chunilal S
BACKGROUND: The ADJUST-PE study showed that an age adjusted D-dimer (AADD) (age years X 10ng/ml if >50 years) combined with an unlikely pre-test probability (PTP) can increase the proportion of older patients whom pulmonary embolism (PE) can be safely excluded but the IL D-dimer HS assay was not assessed.
AIM: To assess the ability of the IL D-dimer HS assay to exclude PE using the AADD.
METHODS: Retrospective analysis of consecutive patients presenting with symptoms of acute PE to one of three Monash Health Emergency Departments (January 2013-January 2014) who had Computer Tomography Pulmonary Angiography (CTPA). In the group with D-dimer, efficiency (proportion of PE excluded based on a combination of unlikely pre-test probability (PTP) and negative D-dimer) was determined using (i) current laboratory (200 ng/ml), (ii) conventional (230ng/ml), and (iii) modified (375ng/ml if age ≥60 years) (iv) AADD cut-offs.
RESULTS: 176 patients with D-dimers were included (mean age 58.5 years; 54.0% males; 71.0% age >50 years). Prevalence of PE in the overall, unlikely and likely PTP groups were 17.0%, 13.0%, and 24.6% respectively. In the unlikely PTP group (115 patients), efficiency for the current, conventional, modified and AADD cut-offs were 9.6% 24.3%, 30.4% and 37.4% respectively.
CONCLUSION: The absolute increase in efficiency of an AADD compared to conventional cut-off using the IL D-dimer HS assay is modest (~10%) and requires prospective validation. Modifying our cut-off to 230ng/ml and systematic implementation of a clinical algorithm including D-dimer testing and PTP is likely a more important first step. This article is protected by copyright. All rights reserved.
PMID: 29869406 [PubMed - as supplied by publisher]