Thyroid function in girls with central precocious puberty

PURPOSE: Obesity is a well-known risk factor for central precocious puberty (CPP). Recently, elevated thyroid stimulating hormone (TSH) was reported in obese youth. However, few data regarding the relationship between CPP and TSH are available. The aim of this study was to evaluate thyroid function in girls with CPP and the relationship between CPP and serum TSH concentration. METHODS: This was a retrospective cross-sectional study. A total of 1,247 girls aged between 6.0 and 8.9 years who had undergone a gonadotropin-releasing hormone (GnRH) stimulation test to determine the presence of puberty were studied. Subjects were classified into CPP (n=554) and non-CPP (n=693) groups according to the results of the GnRH stimulation test. Characteristics and laboratory data of the CPP and non-CPP groups were compared and correlations between those characteristics and laboratory data and TSH concentration were evaluated. Serum TSH concentration in the CPP group was higher than that of the non-CPP group (3.19±1.55 mIU/L vs. 2.58±1.34 mIU/L, P<0.001). RESULTS: Serum free thyroxine (fT4) concentration in the CPP group was notably lower than that of the non-CPP group (1.38±0.14 ng/dL vs. 1.44±0.18 ng/dL, P<0.001). Across all subjects, 149 girls (11.9%) had hyperthyrotropinemia. The prevalence of hyperthyrotropinemia was higher in the CPP group compared to the non-CPP group (15.7% vs. 8.9%, P<0.001). TSH concentrations were positively correlated with age, height, weight, BMI, bone age, bone age advance, insulin-like growth factor 1 (IGF-1), IGF-1 standard deviation score, basal luteinizing hormone (LH), peak LH and basal follicle-stimulation hormone. TSH concentrations were negatively correlated with fT4. Multiple linear regression analysis showed that age (β=0.548, P<0.001) and peak LH (β=0.019, P=0.008) were independently associated with serum TSH concentration. CONCLUSIONS: Hyperthyrotropinemia in girls with CPP tends to be associated with pubertal LH elevation. In conclusion, pubertal onset may be associated with thyroid function.

Clinical characteristics of lower respiratory tract infection in low birth weight children

PURPOSE: Lower respiratory tract infection (LRTI) is one of the most common causes of hospitalization in the pediatric population. In this study, we investigated the clinical characteristics of LRTI, particularly in low birth weight children. METHODS: We reviewed medical records of children at ages 0–6 years with LRTI in Korea University Anam Hospital between January and December of 2014. Clinical data including age, sex, birth history, viral pathogens, blood test results, and clinical courses were collected. RESULTS: In the 828 eligible cases, 617 (74.5%) were pneumonia and followed by bronchiolitis 180 (21.7%) and bronchitis 31 (3.7%). The median age of the subjects was 17 months (interquartile range [IQR], 7–28 months), the median gestational age was 39.0 weeks (IQR, 38.0–40.0 weeks) and the median birth weight was 3,200 g (IQR, 2,900–3,480 g). Sixty-four children (7.7%) were low birth weight (< 2,500 g) and their median gestational age and birth weight were 33.0 weeks (IQR, 30.0–36.0 weeks) and 2,045 g (IQR, 1,565–2,300 g), respectively. The rates of oxygen supplement (17.2% vs. 4.6%, P < 0.001) and systemic steroid use (20.3% vs. 4.7%, P < 0.001) were significantly higher in low birth weight children than normal birth weight children. Respiratory viruses were identified in 82.6% (519 of 628 subjects); RSV was detected in 240 subjects (38.2%), followed by rhinovirus 168 (26.8%) and adenoviruses 75 (11.9%). The distribution of respiratory viruses was not different between normal birth weight children and low birth weight children. CONCLUSION: Low birth weight children show more severe clinical manifestations than normal birth weight children during hospitalization for LRTI, although respiratory viral pathogens were not different. Clinicians should be aware that the severity may be increased when low birth weight children were hospitalized due to low respiratory tract infection.