Bone mineral density and serum bone turnover markers in survivors of childhood acute lymphoblastic leukemia: comparison of megadose methylprednisolone and conventional-dose prednisolone treatments.

During recent decades, the survival rate after childhood acute lymphoblastic leukemia (ALL) has improved substantially; consequently, the long-term side effects of ALL and its treatment have gained attention, of which osteoporosis is one of the most important. The purpose of the present study was to compare the influence of different treatment protocols that include high-dose methylprednisolone (HDMP) versus conventional-dose prednisolone (CDP) for remission-induction therapy on bone mineral density (BMD) and serum bone turnover markers in survivors of childhood ALL after cessation of chemotherapy. Thirty-six boy and 23 girl survivors, treated for ALL, were cross-sectionally studied, at a mean age of 11.7 years (range 6-19). Group 1 (n = 30) received CDP therapy (prednisolone, 2 mg/kg/day, orally) and group 2 (n = 29) received HDMP therapy (prednol-L, 900-600 mg/m2, orally). All other therapies were similar in both groups. Cranial irradiation was added for high-risk patients as soon as possible after consolidation therapy. We found that mean lumbar spine BMD z score value was -1.75 (0.83) SDS in group 1 and -1.66 (1.21) SDS in group 2. There is no difference between both groups (P = 0.736). The mean BMD z scores of prepubertal and pubertal patients were not significantly different in both groups. Comparison of serum bone turnover parameters of the patients revealed no difference between the two groups. Stepwise regression analysis revealed that lumbar spine BMD z scores was predicted by height SDS and the time past since cessation of therapy, but not age at diagnosis, BMI SDS, cranial radiotherapy, and puberty. Our study results showed that HDMP treatment did not deteriorate the bone mass any more than CDP treatment. These results proved that high-dose steroid therapy over a short period of time in remission-induction treatment would not affect the bone mass any more adversely than would conventional doses approximately 3 years after cessation of chemotherapy.

Influence of iodine supplementation on serum insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3) levels in severe iodine deficiency.

Iodine deficiency is an important public health problem worldwide. In addition to severe consequences such as brain damage, developmental delay, deficits in hearing and learning, it also has a negative impact on growth. The negative impact of severe iodine deficiency (SID) on insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) was shown previously. In this study we aimed to analyze the impact of iodine supplementation on growth and growth factors of children with SID. One hundred and four children (63 boys and 41 girls) aged 5-15 years participated in the study. Height standard deviation scores (HSDS), and serum levels of IGF-I and IGFBP-3 were assessed both before and six months after a single dose of iodized oil. Serum levels of free thyroxine (FT4) and thyroid stimulating hormone (TSH) were also analysed to investigate the mechanisms by which alterations of iodine status may influence growth. Pubertal children had lower HSDS six months after iodine supplementation, while that of prepubertal children remained unchanged. IGF-I and IGFBP-3 levels decreased significantly and FT4 levels were suppressed six months after the supplementation, while TSH was normalized. These findings suggest a negative impact of iodine supplementation on growth factors in the short-term, which may be a direct effect of iodine repletion or an indirect effect caused by alterations in thyroid function. It may also be related to the method of supplementation used. Further studies are necessary to resolve these issues, as well as to examine the impact of iodine supplementation on growth in the long-term.

Risk factors for vitamin D deficiency in breast-fed newborns and their mothers.

OBJECTIVES: Vitamin D plays a critically important role in the development, growth, and mineralization of the skeleton during its formative years, and performs an equally essential role in maintaining a healthy mineralized skeleton for adults of all ages. We evaluated the vitamin D status and risk factors for vitamin D deficiency in healthy breast-fed newborns and their nursing mothers. METHODS: Serum 25-hydroxyvitamin D (25OHD), calcium, phosphorus, and alkaline phosphatase levels were measured in 54 newborns and their nursing mothers whose ages ranged from 18 to 38 y. The relation between serum 25OHD level and demographic factors was analyzed. Bone mineral density was measured in the mothers with a serum 25OHD level below 25 nmol/L to determine the extent of bone mineralization. RESULTS: The mean serum 25OHD level in the 54 mothers was 29.11 +/- 10.47 nmol/L. Forty-six percent of the mothers had serum 25OHD levels below 25 nmol/L. The risk factors for low maternal serum 25OHD level were found in decreasing order of importance as follows: low socioeconomic class (odds ratio [OR] = 8.1, P = 0.000), being covered (OR = 4.3, P = 0.023), and low educational level (OR = 3.5, P = 0.033). The mean serum 25OHD level in the newborns was 18.62 +/- 8.00 nmol/L. Eighty percent of the newborns had serum 25OHD levels below 25 nmol/L. There was a significant correlation between the serum 25OHD levels of the newborns and their mothers (r = 0.63, P = 0.01). The most important risk factor for low serum 25OHD level in the newborn was a maternal 25OHD level below 25 nmol/L (OR = 15.2, P = 0.002), followed a covered mother (OR = 6.8, P = 0.011). Bone mineral densitometry showed osteopenia in 40% of the women with serum 25OHD levels below 25 nmol/L. All women were from a lower socioeconomic class and 80% were covered. CONCLUSIONS: Vitamin D deficiency is still a common and serious health problem of women of reproductive age and their babies in developing countries at the outset of a new millennium.