Patients:
This retrospective study included 420 children diagnosed with KD and hospitalized in the department of Pediatrics, Shengjing Hospital of China Medical University between January, 2018 and December, 2020. The children were assigned to three study groups. Group A included those with KD complicated by coronary artery aneurysm (CAA). Group B included those with KD complicated by coronary artery dilation (CAD), and group C included KD without CALs (NCALs). The diagnosis of KD was based on criteria established by the Japanese Kawasaki Disease Research Committee and the American Heart Association (AHA). The criteria included fever of > 38°C lasting at least 5 days without any other explanation and at least four of the following: polymorphous exanthema (a rash of any kind), bilateral bulbar conjunctival injection without exudates, erythema of the oral mucosa including the lips, pharynx, or tongue, peripheral extremity changes including erythema of palms or soles and/or swelling of the hands or feet, and unilateral cervical lymphadenopathy larger than 1.5 cm in diameter[2]. The diagnosis in patients with fevers of ≥ 5 days duration with fewer than four characteristic manifestations was incomplete KD.[2] An incomplete clinical diagnosis of KD can be made in patients with coronary artery disease detected by echocardiography[2]. The diagnoses were confirmed by more than two pediatric cardiologist; other possible diseases were excluded. Patients with incomplete clinical data, presenting with other febrile and exanthematous diseases, such as sepsis, toxic shock syndrome caused by scarlet fever, allergic and rheumatic diseases, and those who were previously found to have congenital heart disease by echocardiography were excluded.
Color Doppler ultrasonography was performed with GE VIVID E9 and Philips iE33 imaging systems and M5S, X5, and S8 probes. The probe frequencies were 1–5 and 2–8 MHz. Children were asleep or in a quiet state in the supine or left decubitus position. Standard sections of the heart were explored at the xiphoid process, apex, parasternal, and suprasternal fossa to explore. We evaluated the maximal internal diameters of the right coronary artery (RCA), the left coronary artery (LCA), left anterior descending artery (LADA), and left circumflex coronary artery (LCxA). Patient coronary artery Z-scores were classified as normal (< 2.5 standard deviations from the mean, normalized for body surface area), dilated (≥ 2.5 to < 4 standard deviations), aneurysmal (≥ 4 standard deviations), or giant aneurysm (> 10 standard deviations) of the maximal internal diameter at the base of the RCA or LADA. This study was approved by the ethics committee of China Medical University.
Clinical examination
Whole blood, plasma and serum samples were collected from patients with acute KD before any treatment with intravenous immune globulin (IVIG). Patient data included white blood cell (WBC) and platelet (PLT) counts, hemoglobin (Hb), neutrophil percentage (N%), eosinophil percentage (E%), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), IVIG resistance, brain natriuretic peptide (NT-proBNP), procalcitonin (PCT), interleukin (IL)-6, serum albumin (ALB), albumen/globulin ratio (A/G), alanine aminotransferase (ALT), aspartate aminotransferase (AST), prothrombin time (PT), fibrinogen (FIB), fibrinogen degradation products (FDP), D-dimer (DD), immunoglobulin (Ig)G, IgM, IgA, Na+, and K+.
Statistical analysis
The statistical analysis of CAL risk was performed with SPSS 23.0 statistical software. Quantitative data were reported as means ± standard deviation, qualitative data were reported as numbers (n) and percentages (%). Quantitative outcome measures were compared by the t-test if the distribution met normality criteria, or by the Mann-Whitney test if the data were not normally distributed. Comparison of the two qualitative outcome measures were done with the chi-square (χ2) test. The three groups were compared in pairs. Univariate logistic regression was significant for variables included in multivariate logistic regression. The logistic regression analysis was conducted to evaluate the potential risk factors for CALs, and the predictive value of each risk factor was estimated by receiver operating curve (ROC) characteristic analysis. P-value of < 0.05 was considered statistically significant.