Background: Mycoplasma pneumoniae (Mp) is an important pathogen that causes respiratory tract infections in children. Data on epidemiology of paediatric Mp infection in China are little known. The aim of this study was to investigate the infection of children with respiratory tract infection in Xi'an from 2017 to 2020, and to explore the epidemiological features of paediatric Mp infection in Northwest China during the past 4 years. Methods: A total of 53,273 paediatric patients diagnosed with respiratory tract infection as the first diagnosis were enrolled. Mp antibody was detected using passive agglutination method. Statistical analysis and epidemiological investigation were carried out on the test results according to different years, seasons, ages and genders. The differences among rates were analyzed by the χ 2 test. The trends among the rates were analyzed by the Poisson regression.Results: A total of 14,375 Mp antibody positive patients were detected, with a total positive rate of 26.98%.The rate of Mp infection in 2017 was significantly higher than other years (χ 2 =431.700; P=0.000), and the rate showed a downward trend year by year [incidence rate ratios (IRR) =0.906; 95% CI: 0.892-0.921; P=0.000]. The rate of Mp infection increased gradually in the order of spring, summer, autumn and winter (IRR =1.078; 95% CI: 1.060-1.097; P=0.000), and peaked in winter (29.08%). As age increased, the positive rate of Mp infection also gradually increased (IRR =1.138; 95% CI: 1.134-1.143; P=0.000). The peak age of Mp infection was between 6 and 12 years, accounting for 51.71%, significantly more compared with other age groups (χ 2 =4203.000, P=0.000). Female children had significantly higher positive rates than male children (χ 2 =527.000; P=0.000). Conclusions: Mp infection mainly occurs related to year, season, age and gender. Understanding the epidemiological characteristics of paediatric Mp infection can contribute to timely treatment and diagnosis, and may improve the prognosis of children with Mp infection.

Background Pregnant women with gestational diabetes mellitus (GDM) often have an increased risk of adverse pregnancy outcomes. The purpose of this study was to explore the prevalence and characteristics of GDM in Xi’an from 2015 to 2021 since the implementation of China’s “Two-Child policy” and to provide a clinical basis for the management of GDM. Methods We analyzed the oral glucose tolerance test (OGTT) results of 152,836 pregnant women who underwent routine prenatal examination at the Northwest Women and Children’s Hospital from 2015 to 2021. Additionally, we analyzed the GDM prevalence and characteristics. Results The prevalence of GDM in the Xi’an urban area was 24.66% and exhibited an increasing trend annually (χ2 for trend = 43.922, p < 0.001) and with age (χ2 for trend = 2527.000, p < 0.001). Consistent with this, the proportion of pregnant women aged 18–25 and 26–30 years decreased significantly with the annual growth (χ2 for trend = 183.279, p < 0.001 and χ2 for trend = 33.192, p < 0.001, respectively). The proportion of pregnant women aged 31–35 and 36–42 years increased gradually annually (χ2 for trend = 134.436, p < 0.001and χ2 for trend = 44.403, p < 0.001, respectively). Of the pregnant women diagnosed with GDM, 71.15% (65.05–74.95%) had abnormal fasting plasma glucose (FPG) values. The highest percentage of patients had a single abnormal OGTT value (68.31%; 65.77–70.61%), followed by two (20.52%; 18.79–22.55%) and three (11.17%; 10.11–11.85%) abnormal values (FPG and 1-h and 2-h plasma glucose (PG). Conclusion The prevalence of GDM among pregnant women in Xi’an region was high, and it had a increasing trend over the period from 2015 to 2021. Notably, the proportion of elder pregnant women, aged 31–42 years, presented a significant rise after the implementation of the universal two-child policy. On the basis of the high incidence of GDM among elder pregnant women and the high rate of abnormal OGTT values (numbe ≥ 2) in pregnant women diagnosed with GDM, the management of GDM should be intensified, and relevant departments should pay more attention to pregnant women of advanced age.