Elevated Serum Selenium in Diabetic Children

ABSTRACT. Twenty-seven diabetic children, 16 girls and 11 boys, 5–18 years of age, with a duration of the disease ranging from 2–15 years, comprised the study group. Thirteen children with a similar age and sex distribution, living in the same area served as healthy controls. All 40 children had a normal growth pattern. The mean serum selenium concentration in the diabetic children, determined by neutron activation analysis, was 7.4 ± 0.8 μg/100 ml (mean ± SD) and in the healthy controls 6.5 ± 0.8 μg/100 ml. The difference between the two groups was statistically highly significant ( p < 0.01). Boys and girls in both groups had nearly identical mean serum selenium levels and no correlation was observed between the selenium concentrations and either the age, weight or height of the children or the indicators of diabetic control. The selenium status in diabetic children has not been reported previously. The possibility of elevated serum selenium in diabetic children in response to altered lipid metabolism is discussed.     

Serum apolipoproteins A-I, A-II and B in diabetic children and matched healthy controls

Serum concentrations of apolipoprotein (apo) A-I. A-II and B were determined in 28 diabetic children (age 3-16 years) and 14 healthy matched controls. In the healthy children the serum apo A-I concentration was 120 +/- 20 arbitrary units (A.U.) (mean +/- S.D.), apo A-II 111 +/- 14 A.U. and apo B 100 +/- 34 A.U. (100 A.U. = mean concentration in adult blood donors). The apo A-I concentration was significantly higher in the diabetic children (134 +/- 13; p less than 0.02) than in the healthy controls. In diabetics apo A-II was 116 +/- 14 A.U. and apo B 106 +/- 21 A.U., values not significantly different from those in the controls. The serum cholesterol concentration in the healthy children correlated strongly to apo A-I and apo A-II, which was not the case in the diabetics. The differences between diabetic and healthy children with respect to correlations between the apolipoproteins and the serum lipids might indicate a different apolipoprotein/lipoprotein lipid relationship in diabetics.     

Dietary Intake, Trace Elements and Serum Protein Status in Young Diabetics

ABSTRACT. Dietary intake of energy and nutrients and its relation to trace element and protein status, as observed in 27 diabetic children and 13 healthy controls are discussed. The diabetic children had consistently higher intakes than the healthy controls in nearly all respects, except for carbohydrate and ascorbic acid. In spite of this, the diabetic children had a significantly lower mean serum magnesium than the healthy controls. It is suggested that hypomagnesemia in diabetic children may be the result of increased urinary loss or diversion of magnesium from normal metabolic pathways in this disease. This review also revealed a significantly higher mean serum selenium level in the diabetic children than in the healthy controls. However, no significant correlation WBS observed between serum selenium concentrations and protein intake, suggesting that a factor other than protein intake underlay the elevated levels of serum selenium. The diabetic children as a group had significantly lower levels of selected serum proteins than the controls, in spite of a significantly higher intake of protein by the diabetic group. It is suggested that both reduced serum proteins and elevated levels of serum selenium in the diabetic children are an expression of altered metabolism in combination with the effects of current modes of insulin treatment in this disease.     

Iodine and selenium deficiency in school-children in an endemic goiter area in Turkey

Endemic goiter is one of the most important health problems in Turkey. However, there are not enough studies associated with iodine and selenium status. This study was carried out to establish the effects of iodine and selenium levels on thyroid gland size and thyroid functions in 73 healthy school-children, 7-12 years old (mean 9.56 +/- 1.77 years), 38 girls (52%) and 35 boys (48%), living in an endemic goiter area. Goiter was found in 32 of the children (43.8%) by palpation, and 56 of the children (76.7%) by ultrasonography. Mean serum T3 and TSH levels were in the upper limit of normal, and mean serum T4 levels were within the normal limits, but mean serum thyroglobulin levels were higher than the normal limits. Mean serum selenium level was 30.84 +/- 23.04 microg/l, and mean urinary iodine level was 3.91 +/- 3.77 microg/dl, appropriate for moderate iodine and selenium deficiency. Thyroid volumes of the children were negatively correlated with serum selenium levels, but there was no correlation with urinary iodine levels and thyroid hormones. In conclusion, school-children in this area had significant goiter problems, probably due to the iodine and selenium deficiencies.     

Concentration of selenium in nutrition and blood serum of diabetic children and adolescents

During 6 days the food of 7 patients of an instruction center for juvenile diabetics contained 60.94 +/- 2.87 micrograms selenium/day. Thereafter the serum selenium concentration was 91.24 +/- 8.57 ng/ml. The corresponding figures for 9 controls of the same age (pupils of a boarding school) were 35.90 +/- 12.24 micrograms selenium/day and 60.94 +/- 10.07 ng/ml, respectively. The differences are the result of the diabetic diet containing more proteins rich in selenium than the food of the controls.     

Real-time sonography for screening of gallbladder dysfunction in children with type 1 diabetes mellitus

The aim of this study was to evaluate the occurrence of gallbladder dysfunction in children with type 1 diabetes mellitus using real-time ultrasonography. The study population consisted of 20 diabetic children (11 male, 9 female; age 11.7+/-2.8 years; diabetes duration 0.5-7 years) with clinically negative neuropathy findings and 15 healthy controls (11 male, 4 female; age 10.5+/-3.7 years). Three-dimensional measurements of the gallbladder were made before and 15, 30, 45, 60 min after intake of diet chocolate. Gallbladder volumes were calculated by the ellipsoid formula. Fasting gallbladder volume of diabetic children (16.9+/-9.5 ml) was significantly greater than that of the controls (10.6+/-5.3 ml; p=0.017). Ejection fraction and maximal contraction showed no significant difference between the two groups. Diabetic patients with multiple microvascular complications had diminished gallbladder motility. There was a negative correlation between BMI and maximal contraction (p<0.05). Nerve conduction velocity was diminished in 45% of the diabetic patients. In conclusion, gallbladder function is preserved in pediatric type 1 diabetic patients with a disease duration less then 10 years, but dilated gallbladder at rest may be an early sign of gastrointestinal autonomic neuropathy and a risk factor for gallstone formation.     

小于胎龄儿青春前期女孩硫化脱氢表雄酮和胰岛素水平的研究

目的探讨小于胎龄儿(SGA)青春前期女孩肾上腺机能初现及是否具有肾上腺机能早现、高肾上腺雄激素血症、高胰岛素血症和胰岛素抵抗现象。方法以符合纳入标准的SGA 39例为研究对象,年龄(7.4±1.7)岁,42例适于胎龄儿(AGA)为对照组,年龄(7.4±1.7)岁。在隔夜空腹12 h后,行身体检查,并抽血检测空腹血糖、胰岛素、硫化脱氢表雄酮(DHEAS)、皮质醇和雌二醇。胰岛素敏感性用空腹血糖与胰岛素乘积的倒数再取自然对数来评价。结果两组中未发现肾上腺机能早现的临床表现,两组间孕母孕龄、年龄、体重指数、空腹血糖、皮质醇、雌二醇和胰岛素敏感性指数差异无统计学意义。SGA组出生体重、研究时的身高和体重均低于AGA组,SGA血清胰岛素和DHEAS水平均高于AGA组(对数转换值:1.076±0.041vs.1.050±0.051,P<0.05;2.637±0.271vs.2.514±0.250,P<0.05)。AGA组DHEAS值在7岁以后出现明显增加,SGA组DHEAS值出现增加的趋势与AGA组比较有所提前。结论AGA女孩肾上腺机能初现的年龄约为7岁,而SGA女孩肾上腺机能初现有始动提前的趋势,青春前期SGA女孩有高肾上腺雄激素血症和胰岛素水平升高的现象,但以胰岛素敏感性指数来评价,尚未发现胰岛素抵抗现象。     

Selenium in Plasma and Erythrocytes in Patients with Down's Syndrome and Healthy Controls

ABSTRACT. The mean plasma selenium concentration (P-Se) in 65 patients with Down's syndrome (DS) did not differ from that in 90 healthy controls. The concentration of selenium in the erythrocytes (E-Se) was higher in DS patients than in controls ( p <0.001). P-Se and E-Se increased progressively with age through childhood in both DS children and controls. The former children, however, started out with higher levels of E-Se and reached adult concentrations earlier (at 7-17 years) than controls (18 years). Adult DS patients and controls did not differ in their mean P-Se or E-Se concentration. There was a significant correlation between P-Se and E-Se both in DS patients and in controls. In DS patients each of these two variables was significantly correlated to glutathione peroxidase (GSH-Px) activity in erythrocytes. A sex difference in the DS children, but not in the controls, was observed with regard to P-Se and E-Se levels, these being higher in DS girls during childhood (0-17 years). This was in accordance with an earlier finding of higher GSH-Px activity in DS girls than in DS boys.     

Effect of carbamezapine and valproic acid on bone mineral density, IGF-I and IGFBP-3

OBJECTIVE: To examine the effect of carbamezapine and valproate on bone mineral density (BMD), IGF-I and IGFBP-3 levels in children. METHODS: The effects of at least 2 years valproic acid and carbamazepine therapy on BMD were evaluated in a cross-sectional and retrospective study. All children were ambulatory, prepubertal, and had normal activity and nutritionally adequate diets. Ambulatory epileptic patients were divided into two groups. Thirty-three patients (group 1; 17 boys, 16 girls; mean age: 8.8 +/- 2.0 years) were treated with valproic acid and 33 patients were treated with carbamazepine (group 2; 20 boys, 13 girls; mean age: 9.7 +/- 1.6 years). The control group consisted of 22 healthy children (13 boys, 9 girls; mean age: 8.9 +/- 2.3 years), who were age- and sex-matched with the patient groups. Children with metabolic bone disease, growth and neurological impairment, signs of malnutrition, or any chronic disease were excluded from the study. RESULTS: BMD values at lumbar spine in both the carbamazepine (-1.69 +/- 0.85 mean L1-4 BMD z-scores, mean 35.5 +/- 12.8 months treatment, and 19,478.6 +/- 6,301.3 mg/kg cumulative dose) and valproic acid (-1.28 +/- 0.80 mean L1-4 BMD z-scores, mean 33.7 +/- 15.0 months treatment, and 22,852.4 +/- 12,477.4 mg/kg cumulative dose) groups were significantly lower than that of the control group (-0.23 +/- 0.87 mean L1-4 BMD z-score). Serum ALP and PTH levels were significantly higher in the carbamazepine-treated group (65.4 +/- 21.1 pg/ml, 767 +/- 267 U/l, respectively) than those of the valproic acid-treated (39.1 +/- 12.8 pg/ml, 561 +/- 166 U/l, respectively) and control groups (36.3 +/- 4.9 pg/ml, 487 +/- 82 U/l, respectively). Serum 25-hydroxyvitamin D of the carbamazepine-treated group (9.8 +/- 3.2 microg/l) was significantly lower than the other groups (15.1 +/- 3.5, 16.6 +/- 4.7 microg/l, respectively). There were eight and 13 patients with plasma intact PTH above reference values in groups 1 and 2, respectively. Valproic acid and carbamazepine therapy results in a hyperparathyroid state and altered vitamin D metabolism, respectively. CONCLUSION: BMD values at lumbar spine were significantly reduced in both carbamezapine and valproic acid treated groups. Valproic acid and carbamazepine therapy do not change IGF-I and IGFBP-3 levels. Altering the hepatic conversion of vitamin D may be the mechanism of carbamazepine-associated reduction in BMD, but the mechanism of decreased BMD in valproate therapy remains unclear.     

Selenium in plasma and erythrocytes in patients with Down's syndrome and healthy controls. Variation in relation to age, sex and glutathione peroxidase activity in erythrocytes

The mean plasma selenium concentration (P-Se) in 65 patients with Down's syndrome (DS) did not differ from that in 90 healthy controls. The concentration of selenium in the erythrocytes (E-Se) was higher in DS patients than in controls (p less than 0.001). P-Se and E-Se increased progressively with age through childhood in both DS children and controls. The former children, however, started out with higher levels of E-Se and reached adult concentrations earlier (at 7-17 years) than controls (greater than or equal to 18 years). Adult DS patients and controls did not differ in their mean P-Se or E-Se concentration. There was a significant correlation between P-Se and E-Se both in DS patients and in controls. In DS patients each of these two variables was significantly correlated to glutathione peroxidase (GSH-Px) activity in erythrocytes. A sex difference in the DS children, but not in the controls, was observed with regard to P-Se and E-Se levels, these being higher in DS girls during childhood (0-17 years). This was in accordance with an earlier finding of higher GSH-Px activity in DS girls than in DS boys.     

Serum osteocalcin and bone alkaline phosphatase in healthy children in relation to age and gender

Biochemical markers of bone formation are important in the study of growth and skeletal metabolism. However, interpretation of their values for children and adolescents is difficult because they depend on many factors such as age, gender, pubertal stage, race, nutritional and health status, specificity of assays and others. Therefore, age and sex specific reference ranges for bone formation markers must be established in a defined paediatric population. The purpose of this study was the investigation of normal serum concentration of osteocalcin (OC) and bone alkaline phosphatase (BALP) in Polish children aged 2-18 years. We studied 121 healthy children (56 girls, 65 boys) divided into 3 age groups of both genders: prepubertal, pubertal and postpubertal. The level of OC was determined by N-MID Osteocalcin One Step ELISA kit (Osteometer Bio Tech, Denmark) and the activity of BALP was measured using an enzyme immunoassay Alkphase-B kit (Metra Biosystems, USA). We observed, that both formation markers showed sigmoid regression curves with increasing age. The peak values of OC and BALP occurred during puberty in girls aged 9-13 years (115.6 +/- 21.3 ng/ml; 108.8 +/- 23.6 U/L) and in boys aged 10-15 years (117.8 +/- 22.3 ng/ml; 118.4 +/- 24.5 U/L). In all children after puberty, we observed a gradual lowering of both markers. However, girls showed decreased postpubertal values of OC and BALP 2-3 years earlier than boys, indicating the earlier completion of puberty in girls. The correlation between OC and BALP was statistically significant (r=0.612; p<0.001) in tested children. The results of this study may establish the reference values for bone turnover markers in Polish healthy children, which will be useful in the diagnosis and monitoring of therapy in bone diseases.     

Treatment of central precocious puberty with an LHRH analog. Effect on growth and bone maturation after 2 years of treatment

Eighteen children (15 girls and 3 boys) with true precocious puberty have been treated with an LHRH analogue (HOE 766, Buserelin suprefact) given subcutaneously during one (n = 11) or two (n = 7) years. Six of 18 children had organic precocious puberty, but their responses to therapy did not show any difference. A satisfactory suppression was achieved in 16 cases with plasma testosterone below 0.5 ng/ml (boys) or estradiol below 25 pg/ml and vaginal maturation index below 35 (girls). The mean annual height gain diminished from 9.5 +/- 0.8 cm during the control year to 7.7 +/- 0.7 cm and 5.1 +/- 0.7 cm during the first and second years of therapy respectively (p less than 0.05). Simultaneously, the mean bone age of 10.4 +/- 0.4 yr at onset of treatment, was 11.4 +/- 0.4 yr after one year and 11.8 +/- 0.3 yr after two years. These changes explain an average increase of predicted height of 5.7 cm after two years of treatment with the LHRH analogue. At least on the basis of these data with two years follow-up, this treatment seems satisfactory. We did not find anti-Buserelin antibodies in any of these patients.     

Immunogenicity and safety of hepatitis A vaccine in children with chronic liver disease

BACKGROUND: Acute hepatitis A superimposed on chronic liver disease has been associated with a more severe course of disease and development of fulminant hepatitis. The aim of this study was to evaluate the immunogenicity and safety of an inactivated hepatitis A virus vaccine in children with chronic liver disease. PATIENTS AND METHODS: This was an open, prospective, and controlled trial with 89 anti-HAV negative children between 1 and 16 years of age studied at a pediatric liver disease and transplantation referral center. Inactivated HAV vaccine (Havrix), from GlaxoSmithKline Biologicals containing 720 Elisa units of alum-adsorbed hepatitis A antigen per 0.5 ml dose was used. Thirty-four pediatric patients with chronic liver disease (mean age: 7.0 +/- 4.86 years) and 55 healthy controls (mean age: 4.8 +/- 2.7 years) received two doses of Havrix vaccine in months zero and six. Seroconversion and anti-HAV titers expressed as geometric mean titers (GMT) in mIU/ml were measured at months one and seven, by a modified Hepatitis A virus antibodies (HAVAB) assay. RESULTS: Seroconversion rates at four weeks after primary immunization were 76% and 94% and the GMT 107.77 and 160.77 mIU/ml in the patient and control groups, respectively. One month after second dose the seroconversion rates were 97% and 100% in the groups with GMT of 812.40 and 2,344.90 mIU/ml. Both doses were well tolerated with no significant adverse events observed. Local injection-site symptoms were the most common reactions reported in both groups. CONCLUSION: Although GMTs were significantly lower in children with chronic liver disease compared to healthy controls, the overall seroconversion rates were not different. Hepatitis A virus vaccine was safe, well-tolerated, and immunogenic in children with chronic liver disease.     

SERUM APOLIPOPROTEINS A-I, A-II AND B IN DIABETIC CHILDREN AND MATCHED HEALTHY CONTROLS

ABSTRACT. Serum concentrations of apolipoprotein (apo) A-I, A-II and B were determined in 28 diabetic children (age 3–16 years) and 14 healthy matched controls. In the healthy children the serum apo A-I concentration was 120 ± 20 arbitrary units (A. U.) (mean ± S. D.), apo A-II 111 ± 14 A. U. and apo B 100 ± 34 A. U. (100 A. U. =mean concentration in adult blood donors). The apo A-I concentration was significantly higher in the diabetic children (134 ± 13; p <0.02) than in the healthy controls. In diabetics apo A-II was 116 ± 14 A. U. and apo B 106 ± 21 A. U., values not significantly different from those in the controls. The serum cholesterol concentration in the healthy children correlated strongly to apo A-I and apo A-II, which was not the case in the diabetics. The differences between diabetic and healthy children with respect to correlations between the apolipoproteins and the serum lipids might indicate a different apolipoprotein/lipoprotein lipid relationship in diabetics.     

小儿血清脑钠素正常参考范围

目的：国外研究显示了血清脑钠素-BNP32和氨基末端脑钠肽(NT-proBNP)水平在小儿心力衰竭诊治中的意义。然而,由于小儿BNP32和NT-proBNP正常范围的缺乏导致其在小儿心脏疾病中的应用受到了限制。该研究测定了正常小儿的BNP32和NT-proBNP水平,为临床应用提供参考。方法：用酶联免疫方法分别测定190名健康小儿血清BNP32和NT-proBNP水平,男95名,女95名,年龄10.60±4.12岁,全部受检者均经体检、心电图等检查证明身体健康。结果：小儿血清BNP32浓度为51.89±48.36pg/mL,第10百分位为27.00pg/mL,第90百分位为75.00pg/mL。血清NT-proBNP浓度为246.04±67.27fmol/mL。两种均无性别间的差异(P>0.05),虽然,女童青春成熟期BNP32和NT-proBNP浓度高于青春前,女童脑钠素高于男童,但均未显示有统计学上的显著差异。结论：该文在国内首次用酶联免疫方法测定中国小儿BNP32和NT-proBNP正常范围,小儿NT-proBNP数据较BNP更为稳定、可靠,为脑钠素水平临床测定提供有价值的参考。     

Effect of antiepileptic drugs on bone mineral density in children between ages 6 and 12 years

We assessed the effects of sodium valproate and carbamazepine monotherapy on bone mineral density (BMD) in children. BMD at the lumbar vertebrae (L1-L4) and radius-ulna was measured by the dual-energy x-ray absorptiometry (DEXA) method in 19 children (9 girls, 10 boys) with uncomplicated epilepsy and in 57 healthy children (28 girls, 29 boys), between the ages of 6 and 12 years. The study patients had been receiving either sodium valproate (n = 13) or carbamazepine (n = 6) monotherapy for more than 6 months. There were no significant differences between the control and study patients in age, height, weight, physical activity, or of serum concentrations of calcium, phosphate, and transaminases (aspartate aminotransferase, alanine aminotransferase). However, the serum alkaline phosphatase concentration was greater in the patient group as compared with the control group. BMD values were lower in girl patients (L1-L4; 0.497 +/- 0.08 vs 0.566 +/- 0.07 g/cm2, p < 0.05), but not in boys (0.534 +/- 0.06 vs 0.530 +/- 0.08 g/cm2). While BMD reduction was 8% in valproate therapy (midregion of radius-ulna; 0.287 +/- 0.03 vs 0.312 +/- 0.04 g/cm2, p < 0.04), it was reduced only 4.5% in the carbamazepine-treated group (0.298 +/- 0.01 vs 0.312 +/- 0.04 g/cm2, statistically not significant), although the mean durations of monotherapy with valproate (1.8 +/- 0.7 years) and carbamazepine (1.7 +/- 0.8 years) were similar. Thus decreased bone mineralization was observed in children with epilepsy, treated with sodium valproate even though treatment was for a rather short time.     

Monitoring of serum alpha-fetoprotein levels in children with chronic hepatitis B virus infection.

Changes in serum alpha-fetoprotein (alpha FP) levels were investigated by radioimmunoassay during the follow-up (17 +/- 12 months, two to three times per year) of 50 children with chronic hepatitis B virus infection (mean age of 8 years, 30 males) and of 35 healthy age- and sex-matched controls. Eleven of 50 were healthy carriers; 7 had chronic persistent hepatitis, 29 had chronic active hepatitis, and 3 had cirrhosis-associated chronic active hepatitis. Serum alpha FP levels in controls were found to be always lower than 5 ng/ml (0.1-4.4 ng/ml, mean +/- SD of 1.34 +/- 1.32 ng/ml). Statistical analysis after logarithmic transformation showed a significant difference between mean levels (ng/ml) in controls and in patients [geometric mean = 0.83 C.L. (95% confidence limits of 1.19/0.58) vs. 3.43 (95% C.L. of 4.79/2.45); p = 0.0001]. Mean values of serum alpha FP levels at entry were higher than those found at the end of the follow-up period [geometric mean = 3 (95% C.L. of 4.69/1.92) vs. 1.48 (95% C.L. of 2.13/0.95); p = 0.038]. Only three patients repeatedly showed high alpha FP levels (76.7, 122.8, and 1,600 ng/ml at entry): alpha FP values became normal after a mean follow-up of 17 +/- 7.8 months as well as liver enzymes, with no changes in serum "e" antigen-antibody and anti-delta antibody status being observed. Mean values of serum alpha FP levels in HBeAg-positive patients were significantly higher than in HBeAg-negative patients both at entry and during the follow-up (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Elevation of serum stem-cell factor in postoperative biliary atresia

BACKGROUND: Biliary atresia (BA) is one of the most common causes of neonatal cholestasis. Stem-cell factor (SCF) has been implicated in the development of fibrosis in various diseases. The objective of the present study was to examine the significant role of SCF in BA. METHODS: Fifty-seven pediatric patients with BA after Kasai operation and 30 healthy children were recruited. The mean ages of BA patients and controls were 6.1 +/- 0.6 years and 6.1 +/- 0.7 years, respectively. The patients were categorized into two groups according to their serum levels of total bilirubin (TBil < 2 mg/dL, no jaundice vs TBil > or = 2 mg/dL, persistent jaundice) and alanine aminotransferase (ALT < 100 vs ALT > or = 100 U/L). The serum SCF levels were determined on commercially available enzyme-linked immunosorbent assay. RESULTS: The mean serum SCF level of the BA children was higher than that of normal controls (748.3 +/- 17.9 pg/mL vs 582.2 +/- 17.3 pg/mL; P < 0.001). Subsequent analysis demonstrated that the BA patients with serum ALT > or = 100 U/L had significantly greater levels of serum SCF compared to those with serum ALT < 100 U/L (796.5 +/- 22.6 pg/mL vs 694.7 +/- 25.0 pg/mL, respectively; P = 0.002). In addition, serum SCF levels were significantly elevated in the patients with portal hypertension (PH) compared with those without PH (810.0 +/- 18.8 pg/mL vs 634.1 +/- 20.1 pg/mL, P < 0.001). CONCLUSION: The current study showed that BA patients had higher serum SCF levels compared with controls. The significant elevation in SCF levels is associated with the presence of PH and the degree of hepatic injury. These findings suggest that SCF may play a part in the pathogenesis of hepatic fibrosis in BA patients after Kasai procedure.     

Serum concentration of retinol, beta-carotene, cholesterol, and triglycerides in Saudi school children

Vitamin A and beta-carotene are often considered as members of a family of antioxidant vitamins that can show protective effects against oxidative stress and some chronic diseases. Data on vitamin A and beta-carotene status in Saudi children are sparse. In the current study the serum concentrations of retinol, beta-carotene, cholesterol and triglycerides were determined in 500 healthy Saudi children aged 6 to more than 18 years. The study group consisted of 247 (49.4 per cent) females and 253 (50.6 per cent) males, living in the Riyadh area of Saudi Arabia. The serum retinol levels in all age groups were within the range reported from industrial countries and in all age groups the mean values were higher than the critical level of 0.2 microgram/ml. No significant difference in serum retinol levels was observed between male and female subjects (p > 0.05), but age was found to be an important covariant of the vitamin. The mean serum beta-carotene concentration in all age groups was significantly higher than previously reported which may suggest an improvement in Saudi children's diets, notably in respect to fruit and vegetable intake. Females seemed to retain a higher level of beta-carotene compared to males which confirmed earlier reports of a positive correlation between age and the beta-carotene level in females. Only males in the age group 6-8.9 years old had a significantly higher level of beta-carotene than their female counterparts; 11.95 +/- 5.85 micrograms/ml compared to 8.53 +/- 3.5 micrograms/ml (p < 0.05).     

The prevalence of microalbuminuria in diabetic children and adolescents and its relation to puberty

The albumin excretion rate (AER) was studied in two groups of diabetic children and adolescents. Twenty-four-hour AER was studied in 75 children with diabetes for 5 years, in 49 children with diabetes for 10 years, in 55 children with diabetes for 10-20 years and in 21 age matched healthy controls. Overnight AER was studied in 129 diabetic children and adolescents with a duration of diabetes varying from 1-14 years. Diabetics exhibited a wide range of AER-values and when expressed per body surface area, diabetic children had significantly higher AER compared to controls. Log transformed AER-values were significantly correlated to age and body surface area in diabetics but not in controls. In the diabetics, log AER was also correlated to systolic and diastolic blood pressure but not to HbA1c. 20% of the diabetics had AER values exceeding the upper value for healthy controls which was 18.5 micrograms/min. 31/35 of them were older than 12 years. In both groups of diabetics, 5% had AER-values exceeding those reported to be predictive for later development of overt nephropathy, the youngest being 16 years old. When comparing diabetic children 0-12 years (i.e. before the maximal growth spurt of puberty) to those older than 12 years, at the same duration of diabetes, the latter group had significantly higher AER-values. No sex difference was found in either age group. It is concluded that after puberty diabetic patients also show evidence of incipient diabetic nephropathy. Thus, routine screening for microalbuminuria is recommended also in pediatric diabetes care after 12 years of age.