- Kawasaki disease (KD) is an inflammatory multiorgan disease of unknown etiology. The most dramatic organ involved is the heart. There were a few studies about cardiac involvement and sterile pyuria. This study guides to determine if sterile pyuria is associated with coronary artery aneurysm (CAA) in KD patients and to consider it as a predicting factor for coronary artery involvement. Forty seven patients with KD were studied by echocardiography in admission and one month later. Urine analysis, complete blood count, erythrocyte sedimentation rate and C-reactive protein were measured in admission. Data were analyzed using SPSS-14 software. Patients' age was ranged from 13 month to 7 years old (mean age of 3.43±1.54 years). Thirty patients (63.8%) were male and 17 patients (36.1%) were female. Cardiac involvement was detected in 32 patients (68%) using echocardiography, of which CAA was reported in 8 cases (17%). Six of CAA (75%) were in association with sterile pyuria, although it was statistically insignificant (P>0.05). Although the majority of patients with CAA had sterile pyuria, this association is not statistically significant, thus it couldn't be considered as a predicting factor for CAA.