PB0256 - D Dimer levels in Children with Kawasaki Disease correlate with disease activity

Background: Kawasaki disease (KD) is the commonest childhood vasculitis. Coronary artery aneurysms (CAA) develop in 20-25% of untreated children . CAA may lead to morbidity and early death.Early diagnosis and treatment with IVIg significantly reduces the risk of development of CAA. IVIg resistance (IVIgR) seen in 10-20% cases, needs alternative treatment. IVIgR and CAA development are difficult to predict at the outset or on admission.

Aims: To assess the role of D dimer levels in children with KD with regards to IVIg resistance and development of coronary artery aneurysms.

Methods: D dimer levels from peripheral blood were estimated in 32 newly diagnosed KD children aged ≤15 years. Follow-up D dimer levels were available in 22 children. A separate group of 26 known cases of KD were recruited and D-dimer was assessed once anytime during their follow up visits. The assay was performed using the HemosIL D dimer HS kit on the ACL TOP coagulation analyser. The D dimer levels were correlated with disease activity , development of CAA or IVIgR .

Results: D dimer levels were significantly higher with disease activity (median- 536.5 ng/ml) vs. in inactive phase during follow up ,( median-107.5 ng/ml), p < 0.001. D dimer level of 190.5 ng/ml could predict activity with a sensitivity of 81% and specificity of 83%. Though D dimer levels were higher in active KD patients with IVIg resistance (median- 860 ng/ml vs. median-531ng/ml in IVIg responsive patients ) and in those with CAA (median- 1227.5 ng/ml) vs. those without (median- 457 ng/ml), statistical significance was not obtained (p values .583 and .134 respectively).

Conclusion(s): D dimer is a reliable predictor of disease activity in KD. Though D dimer levels at admission were increased in patients with CAA and IVIgR, their clinical utility in predicting the same is uncertain and needs validation in a larger cohort.