Usefulness of age-adjusted N-terminal prohormone of brain natriuretic peptide level as a diagnostic marker for incomplete Kawasaki disease in children

Objectives.

The main objective was to assess the diagnostic usefulness of age-adjusted level of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) as a diagnostic marker in children suspected of having incomplete Kawasaki disease (IKD). The secondary aim was to compare the diagnostic yield of NT-proBNP level with the yield of other markers currently recommended by the American Heart Association (AHA).

Methods.

Descriptive cross-sectional study of a case series of patients under the age of 14 years admitted with clinical suspicion of IKD between 2013 and 2017. We analyzed NT-proBNP level adjusted for age. Demographic, clinical, echocardiographic, analytic, and microbiologic findings were gathered from computerized charts. Two independent evaluators made the diagnosis of IKD according to AHA criteria.

Results.

We included 70 cases, and 19 (27%) were diagnosed with IKD. Patients with IKD had higher NT-proBNP levels than patients with other febrile diseases, and the proportion of cases of elevated age-adjusted NT-proBNP level was also higher in the IKD group (84% vs 4%; P<.001). The diagnostic yield of age-adjusted NT-proBNP for IKD was good (area under the receiver operating characteristic curve, 0.90; 95% CI, 0.80–0.99) and significantly higher than the yields for C-reactive protein, erythrocyte sedimentation rate, albumin, and sterile pyuria (P<.001, all comparisons).

Conclusions.

NT-proBNP level may prove to be a valid diagnostic marker for IKD, possibly offering a higher diagnostic yield than the analyses currently recommended for children suspected of having IKD.