Coronary artery complications are the most severe complications in Kawasaki disease (KD). Its cause is unclear but superantigens are considered to influence KD. This study aimed to determine whether coronary artery complications and level of Nterminal pro-brain natriuretic peptide (NT-proBNP) are associated with Mycoplasma pneumoniae (MP) in patients with KD. We studied 142 pediatric patients diagnosed with KD. MP immunoglobulin M (IgM) antibody examination was conducted. All patients underwent echocardiography, and coronary artery dilatation was defined as a coronary Z-score >2.0. We also evaluated their NT-proBNP findings. The independent t-test and Pearson chi-squared test were used to analyze betweengroup differences; a p-value <0.05 was considered statistically significant. Forty children were MP IgM positive. MP IgMpositive patients were older than MP IgM-negative patients. There was no significant difference in the clinical manifestations between the groups. Comparison of the mean Z-score of the coronary artery revealed that only the Z-score of the left anterior descending artery was significantly different between the groups. However, the number of patients with coronary artery dilatation was not significantly different between the groups. Our findings demonstrated no relationship between MP infection and coronary artery dilatation or NT-proBNP levels in patients with KD.

The present study aimed to identify the factors that can clinically predict responses to macrolides treatment in patients with Mycoplasma pneumoniae pneumonia. Of the patients admitted to the pediatrics department of Kwangju Christian Hospital during December 2012 to March 2015, 195 patients who had pneumonia according to findings of chest radiography, positive Mycoplasma IgM, and fever at the time of admission were selected as study subjects. Patients were divided into one group wherein the duration of fever after macrolides treatment was 3 days or less and another group wherein the duration of fever was 4 days or more (169 patients [86.7%] vs 26 patients [13.3%]). In the group with fever duration of 4 days or more, a greater number of patients had a history of atopic dermatitis (3.6% vs 15.4%, p=0.11), and the symptom duration before admission was longer (cough: 4.04 days vs 6.38 days, p<0.001; fever: 3.96 days vs 6.08 days, p<0.001). Moreover, according to laboratory test results in the group with fever duration of 4 days or more, LDH levels were high (648.16 IU/L vs 829.92 IU/L, p=0.001), and there was a significant correlation between LDH levels and the duration of fever after macrolides treatment.

Prevalence of Mycoplasma pneumoniae pneumonia in preschool children has shown a recent increase and macrolideresistant Mycoplasma pneumoniae pneumonia has been reported. We investigated the clinical features of Mycoplasma pneumoniae pneumonia among children of different ages and different years for the most recent seven years. Retrospective analysis was performed on the clinical data of 735 children who were hospitalized due to Mycoplasma pneumoniae pneumonia between January 2006 and December 2012. The children were divided into three groups according to age: the A group (<3 years), B group (≥3 years and <7 years), and C group (≥7 years). In addition, the children were divided into two groups according to the year in which the disease had developed: the early period (2006 and 2007 year), and the late period (from 2010 to 2012 year). The infant group (A group) presented mainly with a shorter duration of fever and more frequent wheezing. In the late period, the interval until improvement after a macrolide was prescribed increased. Clinical features of Mycoplasma pneumoniae pneumonia differed among children of different ages, particularly between infants and school-aged children.