Chinese Pediatric Reference Intervals for Serum Cortisol on IMMULITE 2000.

Clinical interpretation of the test results for cortisol based on continuous reference intervals with appropriate partitions improves pediatric diagnosis; however, these values are available only for Caucasians. To develop the pediatric reference intervals for Chinese population, we examined the serum cortisol levels in 1,143 healthy Chinese children aged 4-18 years (566 boys and 577 girls), using an IMMULITE 2000 Immunoassay System (Siemens Healthcare GmbH). Phlebotomy was performed at 7-9 a.m. for 284 boys and 287 girls and at 1-3 p.m. for the others. They were divided into four age groups according to the Clinical and Laboratory Standards Institute guideline EP28-A3c, with the last group further stratified according to sampling time. Separate reference intervals of 49.6-323.7, 70.9-395.3, and 90.1-448.7 nmol/L were established for children aged 4-8, 9-12, and 13-15 years, respectively. Further, reference intervals of 118.2-464.7 and 71.4-446.7 nmol/L were established for morning and afternoon cortisol levels, respectively, in children aged 16-18 years. Further studies are necessary to transfer and validate these reference intervals in other analytical systems and pediatric populations, and to allow for broader applications.

Vitamin D status among infants, children, and adolescents in southeastern China.

OBJECTIVE: Vitamin D deficiency and insufficiency are global public health problems, which must first be identified before they can be appropriately addressed, and yet information is strikingly lacking in most parts of the Asia and Pacific region. The study aimed to document and account for the actual situation in Wenzhou on the southeastern coast of China. SUBJECTS AND METHODS: Serum 25-hydroxyvitamin D levels among a total of 5845 infants, preschool children, school children, and adolescents aged 1-18 years were examined between March 2014 and February 2015. RESULTS: Their mean levels were (110.2±26.8), (77.5±25.7), (55.6±15.4), and (47.2±13.9) nmol/L, respectively. Older age groups were involved in increasing risk of vitamin D deficiency and insufficiency. There were significant seasonal differences in its median level and prevalence of deficiency and insufficiency among school children and adolescents, but there was no significant sex difference in mean level and prevalence in any age group. CONCLUSIONS: Vitamin D deficiency and insufficiency were prevalent among infants, preschool children, school children, and adolescents in Wenzhou. A vitamin D-rich diet and outdoor activities for 1-2 h per day under the natural conditions favorable to its endogeous synthesis do not suffice. The vitamin D status in Wenzhounese infants excelling over that in the US was the result of its supplementation thanks to the Chinese Medical Association recommendations, which should be consequently extended to more age groups. Life style shaped by socio-economic environments affects vitamin D status. Knowledge on the importance of vitamin D for healthy growth should be popularized.

[Relationship between hepatitis B virus DNA and hepatitis B virus large envelope protein].

OBJECTIVE: To investigate the relationship between HBV DNA and hepatitis B virus large envelope protein (HBV-LP) in patients with chronic hepatitis B. METHODS: Serum HBV DNA was detected by RT-PCR and the HBV-LP was detected by enzyme linked immunosorbent assay in 320 serum samples collected from patients with chronic hepatitis B. RESULTS: There were no significant difference between positive rate of HBV-LP and that of HBV DNA in different HBeAg patterns (P>0.05). Serum HBV-LP levels were closely correlated with HBV DNA copies (r=0.949). CONCLUSION: Serum HBV-LP is a reliable serological marker that can reflect the replication of HBV.