Background/Objectives: Asthma, one of the most common chronic diseases in childhood, and acute bronchiolitis, a leading cause of hospitalization in early childhood, remain significant contributors to morbidity and mortality. Methods: This retrospective cohort study evaluated the efficacy and safety of intravenous magnesium sulfate (IV MgSO₄) as a secondary treatment in pediatric patients with acute asthma exacerbation unresponsive to first-line therapy and in patients with acute bronchiolitis unresponsive to supportive care. A total of 450 patients aged 6 months to 18 years, including 252 with acute asthma exacerbation and 198 with acute bronchiolitis, were included. Results: Significant improvements in peripheral capillary oxygen saturation were observed after IV MgSO₄ administration in both groups (p < 0.001). In the acute asthma exacerbation group, IV MgSO₄ also significantly reduced tachypnea compared to the acute bronchiolitis group (p < 0.001). No adverse effects related to IV MgSO₄ were observed. Conclusions: These findings suggest that IV MgSO₄ may be both beneficial and safe as an early secondary treatment in acute asthma exacerbations.

Occult hepatitis B virus infection is characterized by the presence of hepatitis B virus DNA despite the undetectable hepatitis B surface antigen. This study aimed to determine the prevalence of occult hepatitis B virus infection in children born to hepatitis B surface antigen–positive mothers who received complete immunoprophylaxis. This cross-sectional study included 99 children. All received hepatitis B vaccination and hepatitis B immune globulin within 24 hours after birth. Serological markers and serum hepatitis B virus DNA were assessed in children aged 9 months to 15 years. All children were negative for hepatitis B surface antigen and serum hepatitis B virus DNA. The prevalence of serum-detectable occult hepatitis B virus infection was 0% (95% confidence interval: 0–3.6%). Anti-hepatitis B surface antibody seropositivity (≥ 10 IU/L) was observed in 66.7% of the children. Four children older than 24 months were positive for anti-hepatitis B core IgG antibody and anti-hepatitis B e antibody, possibly reflecting previous exposure without evidence of active infection. In these children, serum hepatitis B virus DNA remained negative at the initial assessment and at the 6- and 12-month follow-up assessments. No serum-detectable occult hepatitis B virus infection cases were identified. Complete immunoprophylaxis appears effective in this population; however, larger prospective studies with serial hepatitis B virus DNA testing are needed.

Background: The aim of this study was to evaluate the clinical and diagnostic utility of metabolic and systemic inflammatory marker indices in adolescent patients with polycystic ovary syndrome (PCOS). Methods: This retrospective case–control study included 63 adolescent girls diagnosed with PCOS, based on the strict presence of both menstrual irregularity and hyperandrogenism, and 63 healthy controls matched for age and body mass index (BMI). Fasting blood glucose (FBG), fasting insulin (FI), and lipid profiles were measured. Metabolic indices, including the Triglyceride-Glucose (TyG) index, Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), and Metabolic Score for Insulin Resistance (METS-IR), as well as systemic inflammatory indices (Systemic Immune-Inflammation Index (SII), Systemic Inflammation Response Index (SIRI), and the Aggregate Index of Systemic Inflammation (AISI)), were calculated. The diagnostic performance of these markers was evaluated using Receiver Operating Characteristic (ROC) curves and binary logistic regression analyses. Results: No statistically significant difference was observed between the PCOS and control groups in terms of age and BMI (p > 0.05). FBG levels (p = 0.001) and the TyG index (p = 0.028) were found to be significantly higher in the PCOS group. However, no significant differences were observed between the groups in terms of other metabolic indices (HOMA-IR, METS-IR) and systemic inflammatory markers (SII, SIRI, AISI). In the ROC analysis, only the TyG index demonstrated statistically significant but weak discriminatory power for PCOS (AUC = 0.614; 95% CI: 0.515–0.712; p = 0.028). Furthermore, binary logistic regression analysis revealed that the TyG index was not an independent predictor of PCOS after adjustment. Conclusions: While early metabolic signals such as elevated FBG and TyG index were detected, the evaluated systemic inflammatory indices did not demonstrate significant differences. However, the weak discriminatory capacity of the TyG index and the failure of other composite indices restrict their clinical utility. Therefore, these biomarkers cannot be recommended as reliable standalone diagnostic tools in adolescent PCOS.