Delayed diagnosis of Kawasaki disease in Malaysia: Who is at risk and what is the outcome.

Background: Data on the delayed diagnosis of (KD) is limited. This study aimed to determine the prevalence and trend of delayed diagnosis over time and identify the associated risk factors in Malaysia.

Methods: This retrospective, observational, population-based study involved all children with KD registered in Johor Kawasaki Clinical Registry over 10 years (January 2010 and December 2019). The prevalence of delayed diagnosis and its trend over time was calculated. Multivariable binary logistic regression was used to identify the independent risk factors for delayed diagnosis.

Results: There were 556 cases of KD, with 28% having incomplete criteria, 11% atypical presentation, while 10% developed a coronary aneurysm. The overall prevalence of delayed diagnosis was 9.9% (95% confidence interval (CI): 7.6-12.7%). There was a statistically significant decrease in delayed diagnosis over time (P = 0.008), with the latest rate of 4.6%. The majority of delayed diagnoses were due to failure to diagnose the disease during the initial consultation. Independent risk factors for delayed diagnosis were children older than 1 year, diagnosis before 2015, atypical presentation, and incomplete KD, with adjusted odds ratios (ORs) of 2.7, 2.3, 4.3, and 3.6, respectively. Compared to early diagnosis of KD, delayed diagnosis was significantly associated with coronary aneurysms (27.3% vs. 8.2%, P < 0.001, OR 4.2, [95% CI: 2.1-8.3]).

Conclusions: One-tenth of cases of KD were diagnosed late, but it has improved over time. Children > 1 year, presenting with atypical presentation, and incomplete criteria are associated with late diagnosis.