Delayed diagnosis of Kawasaki disease: risk factors and outcome of treatment.

Background: Kawasaki disease (KD) is associated with a high incidence of coronary artery aneurysms in untreated children. Treatment with intravenous immunoglobulin (IVIG) within the 1st 10 days of illness reduces by approximately fivefold the prevalence of coronary artery abnormalities (CAA). Data regarding delayed diagnosis of KD in Thailand have not been reported in the literature.

Aims: To determine the prevalence, risk factors and outcome of delayed diagnosis of KD in Thai patients.

Methods: We retrospectively reviewed the medical records of patients at Chiang Mai University Hospital diagnosed as KD during 2000-2008. Patients were classified into two groups: Group I were diagnosed ≤10 days of fever and Group II were diagnosed >10 days of fever.

Results: Of 170 patients, 150 were in Group I [mean (SD) fever 7 (1·45) d] and 20 (11·7%) in Group II [mean (SD) fever 15 (4) d]. There were no statistical differences between the two groups in age, gender, number of KD clinical manifestations or laboratory results, except that Group II were of lower weight (p = 0·01). Group II were younger (p = 0·09) and had more incomplete criteria (p = 0·09) but the differences were not statistically significant. Group II had a higher incidence of CAA (75% vs 19%) (p<0·001), more severe CAA and more resistant cases (31·2% vs 9·5%) (p = 0·04).

Conclusion: Patients with delayed diagnosis of KD have a higher risk of developing CAA and of a more severe outcome for coronary artery disease. Education is needed to make healthcare providers and physicians more aware of KD, especially in small children or those with incomplete KD.