[Vitamin D level in children with bloodstream infection].

OBJECTIVE: To investigate the difference in serum 25(OH)D level between children with bloodstream infection and healthy children. METHODS: A case-control study was conducted among 60 children with bloodstream infection who were hospitalized between January 2010 and December 2013 and had positive results of two blood cultures. Meanwhile, 60 aged-matched healthy children who underwent physical examination during the same period of time were enrolled as the healthy control group. Chemiluminescence was applied to measure the serum 25(OH)D level, and the constituent ratios of children with different serum 25(OH)D levels were compared between the two groups. RESULTS: The bloodstream infection group had a significantly lower serum 25(OH)D level than the healthy control group (P<0.01). Compared with the healthy control group, the bloodstream group had significantly lower constituent ratios of children with normal Vitamin D level (8% vs 35%) or vitamin D insufficiency (22% vs 43%) (P<0.05). Compared with the healthy control group, the bloodstream group had significantly higher constituent ratios of children with vitamin D deficiency (42% vs 13%) or severely vitamin D deficiency (28% vs 8%) (P<0.01). CONCLUSIONS: Vitamin D insufficiency prevails among children, and children with bloodstream infection have a significantly lower serum 25(OH)D level than healthy children.

[Effect of low-dose methylprednisolone on serum TNF-α level in children with Mycoplasma pneumoniae pneumonia].

OBJECTIVE: To investigate the effect of low-dose methylprednisolone on serum tumor necrosis factor alpha (TNF-α) level in children with Mycoplasma pneumoniae pneumonia (MPP). METHODS: A case-control study was conducted among 38 children with MPP who received treatment in the Affiliated Hospital of Yan'an University between January and December 2012, and who had not received glucocorticoids before hospitalization. They were randomly divided into methylprednisolone treatment (n=20) and conventional treatment groups (n=18). The methylprednisolone treatment group was administered with methylprednisolone (1 mg/kg·d) by intravenous drip for three days in addition to conventional treatment. Serum samples were collected from both groups before treatment and on days 4 and 7 of treatment. Twenty-five children who underwent physical examination in the healthcare clinic during the same period were randomly selected as a normal control group, and serum samples were collected on the same day that the physical examination was performed. Serum TNF-α levels in the three groups were measured using enzyme-linked immunosorbent assay. RESULTS: On admission, the methylprednisolone treatment and conventional treatment groups had significantly higher serum TNF-α levels than the normal control group (P<0.01), but there was no significant difference between the methylprednisolone treatment and conventional treatment groups. On days 4 and 7 of treatment, the methylprednisolone treatment group had significantly lower serum TNF-α levels than the conventional treatment group (P<0.05; P<0.01). On day 7 of treatment, there was no significant difference in serum TNF-α level between the methylprednisolone treatment and normal control groups, but the conventional treatment group still had a significantly higher serum TNF-α level than the normal control group (P<0.01). CONCLUSIONS: Low-dose methylprednisolone can significantly decrease serum TNF-α level and inhibit inflammatory response in children with MPP, and may reduce damage caused by inflammatory response.