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Objective:

Vitamin D deficiency is an unrecognized epidemic and a common health problem worldwide. This study was conducted to evaluate the vitamin D status in children living in Jeddah, Saudi Arabia and to study its relation to various variables.

Materials and Methods:

A cross-sectional study was conducted in the pediatric clinic in Jeddah Clinic Hospital-Kandarah, Jeddah, KSA, from October through December 2010, in which 510 healthy children aged 4–15 years were enrolled. Serum calcium, phosphorus, alkaline phosphatase and 25-hydroxyvitamin D [25(OH)D] were measured. Dietary vitamin D intake and duration of daily sunlight exposure were determined. 25(OH)D levels <20 ng/mL and <7 ng/mL were defined as relative and severe vitamin D deficiency, respectively.

Results:

The mean concentration of 25(OH)D was 13.07 ± 7.81 ng/mL. Seventy subjects (13.72%) had normal 25(OH)D level ranging 20–70 ng/mL. Three hundred (58.82%) had relative 25(OH)D deficiency and 140 (27.45%) had severe deficiency (P=0.000). 220 (43.14%) subjects were males and 290 (56.86%) were females having a statistically significant higher incidence of 25(OH)D deficiency (P=0.019). 54.9% were Saudis, 27.45% were Yemenis and 11.76% were Egyptians. Saudis and Yemenis were more subjected to 25(OH)D deficiency in comparison to Egyptians and other nationalities (P=0.01). There were significant inverse correlations between 25(OH)D levels and bony aches (P=0.000). 56.25% of asymptomatic children had vitamin D deficiency (P=0.000). Duration of sunlight exposure and daily intake of vitamin D had significant effects on serum level of vitamin D (P=0.000).

Conclusions:

A high prevalence of vitamin D deficiency in children living in Jeddah was observed in this study. Vitamin D supplementation of food products can prevent vitamin D deficiency in these children.

Objective: Insulin-like growth factor binding protein-4 (IGFBP-4), inhibits IGF actions under a variety of experimental conditions. Parathyroid hormone (PTH), 1.25-hydroxy(OH)vitamin D, IGF-I, IGF-II and transforming growth factor (TGF)-b are the major regulators of IGFBP-4 production in vitro. However, little is known about the in vivo regulation of circulating IGFBP-4 in humans.

Methods: We measured serum concentrations of calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), PTH, vitamin D, IGF-I, IGFBP-3, and IGFBP-4 in infants (n=22) with nutritional rickets before and after treatment of rickets with vitamin D (300 000 U single dose po).

Results: The mean±SD age of the patients was 1.3±1.6 years (range 0.2-3). Serum Ca and P increased, whereas ALP and PTH decreased after treatment (Ca from 6.6±1.4 to 9.5±1.6 mg/dL, P from 3.9±1.4 to 5.4±0.8 mg/dL, ALP from 2590±2630 to 1072±776 IU/mL and PTH from 407±248 to 27.4±20.8 ng/dL, respectively). Vitamin D levels were low (7.8±2.5 ng/mL) and increased after treatment (18.1±4.0 ng/mL, p<0.001). Serum IGF-I and IGFBP-3 levels both increased after treatment (IGF-I: 13.5±12.2 vs. 23.7±14.2 ng/mL, p<0.001 and IGFBP-3: 1108±544 vs. 1652±424 ng/mL, p<0.001). However, serum IGFBP-4 levels did not change significantly after treatment (18.8±8.0 vs. 21.5±4.8 ng/mL). No correlation between PTH and IGF-I, IGFBP-3 or IGFBP-4 was detected. Significant correlations were observed between PTH and ALP (r=0.53, p<0.05), and between IGF-I and IGFBP-3 (r=0.46, p<0.05).

Conclusion: The results demonstrate that contrary to in vivo studies, circulating IGFBP-4 levels are not influenced by secondary hyperparathyroidism in vitamin D deficiency rickets since IGFBP-4 levels did not change after normalization of PTH with vitamin D treatment.

Conflict of interest:None declared.

One hundred Asian schoolchildren provided evidence of the relationships between radiological and biochemical evidence of rickets in a vitamin D-deficient population. In a retrospective study of the X-rays of 56 children the variables serum alkaline phosphatase, inorganic phosphorus and age provided a discriminant function which correctly classified 10 of 11 children with radiological evidence of rickets and 44 of 45 children with negative or marginally abnormal X-rays. When the discriminant function was applied to a prospective study of 44 children, three children with radiological evidence of rickets were correctly classified together with 38 of the remaining 41 children with negative or marginally abnormal X-rays. Serum alkaline phosphatase was the most important variable in the discriminant analysis, followed by serum inorganic phosphorus and age. Low levels of serum 25-hydroxy vitamin D (25-OHD) are of little value in predicting the severity of radiological evidence of rachitic bone disease in a vitamin D-deficient population.

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Aim: To determine the prevalence of vitamin D hypovitaminosis among obese and overweight schoolchildren.

Design: A cross−sectional population based sample.

Methods: In a cross−sectional study, 301 students (177 girls and 124 boys) aged 11−19 years were selected by multistage stratified sampling design. Subjects were classified according to their body mass index as obese, overweight and normal. Serum 25−hydroxyvitamin D (25−OHD), intact parathyroid hormone (iPTH) and alkaline phosphatase (ALP) were measured in late winter months. Vitamin D deficiency was defined as a 25−OHD 20 ng/ml.

Results: The prevalence of hypovitaminosis D was found as 65% in all students. Vitamin D deficiency was found in 12% and insufficiency in 53% of all students. Vitamin D deficiency in female students was about two times more common than in males. In obese and overweight schoolchildren with hypovitaminosis D, serum 25−OHD levels decreased as BMI increased. There were no correlations between serum 25−OHD and ALP and iPTH levels.

Conclusion: Vitamin D deficiency and insufficiency are common in obese and overweight schoolchildren, especially in girls. Obesity could be a risk factor in terms of hypovitaminosis D in adolescents. Vitamin D supplementation should be administered particularly to adolescent girls.

Conflict of interest:None declared.

Objective:

To study the reported practices of knowledge about and attitude towards smoking among nursing and medical laboratory technology (MLT) students, College of Medicine, King Faisal University at Dammam and Al-Khobar.

Setting:

College of Medicine, Dammam and King Fahd Hospital of the University, Al-Khobar, Saudi Arabia

Methods:

A cross-sectional approach involving a sample of 266 students and interns (152 nursing and 114 MLT), which included all enrolled students in the academic year (1998/1999). A self-administered questionnaire was used to collect data covering knowledge, practice and attitude to smoking. SPSS was used for statistical analysis.

Results:

The overall smoking prevalence was low (5.6%), slightly higher among nursing (6.6%) versus MLT (4.4%) students. Knowledge of and attitude towards smoking was generally satisfactory in both groups, although deficient in some key areas, such as the addictive nature of smoking, some of its consequences on health, and difficulty of quitting.

Conclusion and Recommendations:

The prevalence of smoking among nursing and MLT students is generally low but their knowledge and attitude need improvement. Health education on facts, dangers and consequences of smoking should start as early as the primary school, and should continue throughout the education of future health professionals (role models for the community).

Serum levels of calcium, phosphorus, alkaline phosphatase, and 25 hydroxy-vitamin D (25-OH-D3) were measured in normal and malnourished children with and without rickets. Children with rickets had clinical, biochemical, and x-ray evidence of the disease; most of them were malnourished. 25-OH-D3 levels were lower than in normal children. After treatment with vitamin D their condition improved. 25-OH-D3 levels were also found to be reduced in malnourished children without rickets. These studies show that rickets is common in malnourished children. Inadequate exposure to sunlight appears to be the factor mainly responsible for the high incidence of the disease. In addition, malnutrition perhaps contributes to the development of rickets.

Objective: Adiponectin and its receptors are known to be expressed in osteoblasts and may have important functions in normal bone cells. The aim of this study was to investigate the effect of vitamin D therapy on serum adiponectin levels in children with vitamin D deficiency rickets (VDDR).

Methods: 21 patients with VDDR were included in the study. Patients were treated with 300,000 U D3 (IM) and calcium lactate (50mg/kg/ day, PO, for 10 days). Anthropometric parameters and serum biochemical markers including calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), intact parathormone (iPTH), 25-hydroxyvitamin D (25(OH)D), and adiponectin levels were measured before and after one month of therapy.

Results: Weight and length, but not BMI, increased significantly after treatment. Serum 25(OH)D level increased significantly after treatment, while serum adiponectin level decreased (4.21±1.84 vs 52.73±17.63 ng/ml, p<0.000; 150.1±66.14 vs 84.29±9.06 mg/ml, p<0.000, respectively). No significant correlations were found between serum adiponectin and 25(OH)D levels before and after treatment or between delta adiponectin concentrations and delta 25(OH)D levels.

Conclusion: Serum adiponectin levels are increased in patients with VDDR, a finding which is probably related to increased osteoblastic activity.

Conflict of interest:None declared.

We investigated the vitamin D status and the effect of vitamin D supplementation in Korean breast-fed infants. The healthy term newborns were divided into 3 groups; A, formula-fed; B, breast-fed only; S, breast-fed with vitamin D supplementation. We measured serum concentrations of vitamin D (25OHD3), calcium (Ca), phosphorus (P), alkaline phosphatase (AP), intact parathyroid hormone (iPTH) and bone mineral density (BMD) at 6 and 12 months of age. Using questionnaires, average duration of sun-light exposure and dietary intake of vitamin D, Ca and P were obtained. At 6 and 12 months of age, 25OHD3 was significantly higher in group S than in group B (P<0.001). iPTH was significantly lower in group S than in group B at 6 months (P=0.001), but did not differ at 12 months. Regardless of vitamin D supplementation, BMD was lower in group B and S than in group A (P<0.05). Total intake of vitamin D differed among 3 groups (P<0.001, A>S>B), but total intake of Ca and P were higher in group A than in group B and S (P<0.001). In conclusion, breast-fed infants show lower vitamin D status and bone mineralization than formula-fed infants. Vitamin D supplementation (200 IU/day) in breast-fed infants increases serum 25-OH vitamin D3, but not bone mineral density.

OBJECTIVE

To investigate via the vitamin D status whether patients with peripheral arterial disease (PAD) tend to develop vitamin D deficiency that in turn influences their clinical symptoms.

DESIGN

Cross-sectional.

SETTING

University hospital.

PATIENTS AND PARTICIPANTS

Three hundred twenty-seven patients were evaluated; subjects with secondary causes of bone disease or bone active medication were excluded. One hundred sixty-one patients with either PAD stage II (n = 84) or stage IV (n = 77) were enrolled and compared to 45 age- and sex-matched healthy controls.

MEASUREMENTS AND MAIN RESULTS

All patients underwent determinations of serum chemistry, 25-hydroxyvitamin D (vitamin D3) intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), and osteocalcin and were further stratified according to an individual restriction score into 3 groups: mildly, moderately, or severely restricted in daily life due to the underlying disease. Patients with PAD IV showed significantly lower vitamin D3 (P = .0001), and calcium (P = .0001) values and significantly higher iPTH (P = .0001), osteocalcin (P = .0001) and ALP (P = .02) levels as compared to patients with PAD II. Patients considering themselves as severely restricted due to the underlying disease showed lower vitamin D3 and higher iPTH levels than those who described only a moderate (vitamin D3: P < .001; iPTH: P < .01) or mild (vitamin D3: P < .001; iPTH: P < .001) restriction in daily life.

CONCLUSION

Patients with PAD IV, especially those who feel severely restricted due to the disease, are at high risk of developing vitamin D deficiency, secondary hyperparathyroidism, and ultimately osteomalacia due to immobilization and subsequent lack of exposure to sunlight, all of which in turn lead to further deterioration. Monitoring of vitamin D metabolism and vitamin D replacement therapy could be a simple, inexpensive approach to mitigating clinical symptoms and improving quality of life in patients with advanced PAD.

BACKGROUND

Studies in 1980s and 1990s indicated that vitamin D levels in the ethnic Saudi Arabian population were low but no studies since that time have evaluated vitamin D levels among healthy young or middle-aged Saudi men. Thus, we assessed the serum level of 25-hydroxyvitamin D (25OHD) among healthy Saudi Arabian men living in the Eastern Province.

SUBJECTS AND METHODS:

One hundred males aged 25-35 years (the age range of peak bone mass) and 100 males aged 50 years or older were randomly selected and evaluated clinically, including measurement of serum calcium, parathyroid hormone (PTH) and serum 25OHD levels. Vitamin D deficiency was defined as a serum level of 25OHD of ≤20 ng/mL and insufficiency as a serum level between >20 ng/mL and <30 ng/mL and normal ≥30 ng/mL.

RESULTS:

The mean (SD) age of subjects in the younger age group was 28.2 (4.5) years. Twenty-eight (28%) had low 25OHD levels; 10 (10%) subjects were vitamin D deficient with a mean level of 16.6 (3.4) ng/mL and 18 (18%) were vitamin D insufficient with a mean level of 25.4 (2.7) ng/mL. In the older age group, the mean age was 59.4 (15.6) years and 37 (37%) had low 25OHD; 12 (12%) subjects were deficient with a mean 25OHD level of 16.7 (3.4) ng/mL and 25 (25%) were insufficient with a mean 25OHD level of 25.3 (3.3) ng/mL.

CONCLUSION:

The prevalence of vitamin D deficiency among healthy Saudi men is between 28% to 37%. Vitamin D deficiency among young and middle age Saudi Arabian males could lead to serious health consequences if the issue is not urgently addressed.

Objective

To describe the prevalence and clinical characteristics of transient hyperphosphatasemia (TH) in a cohort of healthy infants and toddlers.

Patients and Methods

We performed a secondary data analysis of children enrolled in a study examining the epidemiology of vitamin D deficiency among healthy infants and toddlers. Children aged 8 to 24 months were enrolled at well-child visits conducted from 2005 - 2007 in an urban primary care pediatric clinic. Children with a chronic disease or using medications known to affect bone metabolism were excluded. At enrollment, we collected data regarding child age, gender, height, and weight; and maternal race/ethnicity. We measured serum levels of alkaline phosphatase, 25-hydroxyvitamin D, parathyroid hormone (PTH), calcium, magnesium and phosphorus. We divided participants into three categories, based on serum AP levels at enrollment: normal (AP 110 to 400 U/L), intermediate (AP >400 to 1000 U/L), and TH (AP >1000 U/L). We used the Fisher exact test and analysis of variance to evaluate differences in clinical characteristics among the three groups.

Results

Nine of 316 children (2.8%) had an AP > 1000 U/L (mean 2165 U/L, range 1006 to 4293 U/L). Sixteen children (5.1%) had an intermediate serum AP (mean 544 U/L, range 423 to 835 U/L). Mean weight-for-age z-score, length-for-age z-score and weight-for-length z-scores were similar across all three AP groups. Compared to the 291 children without TH, children in the intermediate AP and TH groups had similar mean serum levels of 25-hydroxyvitamin D, PTH, calcium, magnesium, and phosphorus.

Conclusions

TH appears to be a relatively common condition among healthy infants and toddlers. TH was not associated with anthropometric measures, vitamin D status, PTH, or serum minerals. Recognition of this benign condition is important to avoid unnecessary investigations.

Summary

Vitamin D deficiency is very common in non-western immigrants. In this randomized clinical trial, vitamin D 800 IU/day or 100,000 IU/3 months were compared with advised sunlight exposure. Vitamin D supplementation was more effective than advised sunlight exposure in improving vitamin D status and lowering parathyroid hormone levels.

Introduction

Vitamin D deficiency (25-hydroxyvitamin D [25(OH)D] < 25 nmol/l) is common among non-western immigrants. It can be treated with vitamin D supplementation or sunlight exposure.

Methods

To determine whether the effect of vitamin D3 supplementation (daily 800 IU or 100,000 IU/3 months) or sunlight exposure advice is similar with regard to serum 25(OH)D and parathyroid hormone (PTH) concentrations. Randomized clinical trial in 11 general practices in The Netherlands. Non-western immigrants, aged 18–65 years (n = 232) and serum 25(OH)D < 25 nmol/l were randomly assigned to supplementation (daily 800 IU or 100,000 IU/3 months) or advice for sunlight exposure for 6 months (March–September). Blood samples were collected at baseline, during treatment (3 months, 6 months), and at follow-up (12 months). Statistical analysis was performed with multilevel regression modelling.

Results

The intention-to-treat analysis included 211 persons. Baseline serum 25(OH)D was 22.5 ± 11.1 nmol/l. After 6 months, mean serum 25(OH)D increased to 53 nmol/l with 800 IU/day, to 50.5 nmol/l with 100,000 IU/3 months, and to 29.1 nmol/l with advised sunlight exposure (supplementation vs sunshine p < 0.001). Serum PTH decreased significantly in all groups after 3 months, more in the supplementation groups than in the advised sunlight group (p < 0.05). There was no significant effect on physical performance and functional limitations.

Conclusion

Vitamin D supplementation is more effective than advised sunlight exposure for treating vitamin D deficiency in non-western immigrants.

Thirty patients with thalassemia major receiving repeated blood transfusion were studied to see their serum parathyroid hormone (PTH) and calcium status. Serum PTH, serum and 24 h urinary calcium, and serum alkaline phosphatase, phosphorus, and albumin-corrected calcium levels were determined. Half of these patients, in addition to transfusion, were also supplemented with vitamin D (60,000 IU for 10d) and calcium (1500 mg/day for 3 months). Serum PTH, and serum and 24 h urinary calcium concentrations of the patients receiving transfusions were found to be significantly reduced while their serum alkaline phosphatase, phosphorus, and albumin-corrected calcium levels were not significantly altered when compared to the respective mean values for the control group. Vitamin D and calcium supplementation significantly increased their serum PTH and calcium levels. Supplementations also increased urinary excretion of calcium. The results thus suggest that patients with thalassemia have hypoparathyroidism and reduced serum calcium concentrations that in turn were improved with vitamin D and calcium supplementation.

Determination of vitamin D status in different age-groups in a community and in different climates of a country is necessary and has important implications for general health. The study was conducted to determine the prevalence of vitamin D deficiency among the adult population of Isfahan, a centrally-located city in Iran. In this cross-sectional study, 1,111 healthy people—243 men and 868 women—aged 41.4 (mean 14 and range 20-80) years, who attended a single-consultation outpatient clinic, were selected. Serum 25-hydroxy vitamin D (25-OHD), parathyroid hormone (PTH), calcium and phosphorus concentrations were measured. Mild, moderate and severe vitamin D deficiencies were defined as 25-OHD values of 20-30 ng/mL, 10-20 ng/mL, and <10 ng/mL respectively. The median (range) concentrations of 25-OHD were 21 (4.0-105.0) ng/mL in males and 18 (1.5-117) ng/mL in females (p=0.05). The prevalence of mild, moderate and severe vitamin D deficiencies among the adult population was 19.6%, 23.9%, and 26.9% respectively. Vitamin D deficiency was more prevalent among women (p=0.001) and younger age-group (p=0.001). Medians of 25-OHD in spring-summer and autumn-winter were 21 ng/mL and 18 ng/mL respectively (p=0.005). The prevalence of severe vitamin D deficiency was higher in autumn-winter than in spring-summer (odds ratio=1.6, 95% confidence interval 1.2-2.2, p=0.001). The prevalence of vitamin D deficiency was high in a sunny city—Isfahan— especially among women and younger population. The high prevalence of vitamin D deficiency in this city emphasizes the necessity of vitamin D supplementation as more exposure to sun is limited due to the type of clothing required by current law.

Vitamin D deficiency rickets (VDDR) is a disorder biochemically characterized by elevated serum alkaline phosphatase (ALP) activity, normal or decreased serum calcium (Ca) and inorganic phosphate concentrations, secondary hyperparathyroidism and decreased serum 25−hydroxyvitamin D (25(OH)D) levels. In stage 1 VDDR, urinary amino acid and phosphate excretion are normal with minimal or no findings of rickets on radiographs. Pseudohypoparathyroidism (PHP) is an inherited disorder characterized by end−organ resistance to parathormone (PTH). VDDR occasionally resembles PHP type 2 in clinical presentation and biochemical features, creating difficulties in the differential diagnosis of these two entities. Here we report an infant diagnosed with VDDR. In addition to inadequate vitamin D intake, usage of antiepileptic drugs (AED) may have led to the worsening of the vitamin D deficiency. The patient presented with a history of febrile convulsions, for which he received phenobarbital treatment. The initial findings of hypocalcemia, hyperphosphatemia and normal tubular reabsorption of phosphate, mimicking PHP 2, responded well to vitamin D and oral Ca treatment with normalization of serum Ca, phosphorus (P), ALP and PTH levels

Conflict of interest:None declared.

In an effort to prevent rickets and vitamin-D deficiency in healthy infants, the American Academy of Pediatrics recommends a supplement of 200 IU per day of vitamin D to all breastfed and nonbreastfed infants unless they consume at least 500 ml per day of vitamin-D-fortified formula or milk. Case reports of infantile vitamin-D-deficient rickets secondary to maternal vitamin-D deficiency have been reported but focused on mothers who had predictable risk factors for such a deficiency. We report on an infant with vitamin-D-deficient rickets who did not have nutritional risk factors and whose mother did not have nutritional or medical risk factors for such a deficiency. We conclude that the current vitamin-D supplementation guidelines be extended to all infants, regardless of feeding volume or source, or at least to all infants born to dark-skinned mothers.

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The prevalence of vitamin D deficiency was reassessed in April and May 1971, 10 years after the discovery of widespread late rickets and osteomalacia in the Glasgow Pakistani community. Evidence of vitamin D deficiency was found in 28 out of 115 adults and children examined (24%). Children at the age of puberty were most severely affected by rickets, whereas most infants and younger children in the survey were protected by vitamin D supplements. Mild biochemical osteomalacia was common in Pakistani women.

A total of 21 Pakistani and Indian children with rickets were admitted to Glasgow hospitals during 1968-70. These comprised 10 children with infantile rickets and 11 with late rickets. Four of the latter group required osteotomy for severe rachitic deformity.

Late rickets and osteomalacia in Pakistani and Indian immigrants are not primarily due to nutritional deficiency of vitamin D, though the high phytate content of their diet may be of aetiological importance. A combination of environmental, social, and endogenous factors, the relative importance of which is not at present clear, may also be involved. Advice on the prophylaxis of vitamin D deficiency should be given to all Pakistani and Indian communities in the United Kingdom.

Background

Vitamin D deficiency, an important risk factor for osteoporosis and other chronic medical conditions, is epidemic in the United States. Uninsured women may be at an even higher risk for vitamin D deficiency than others owing to low intake of dietary and supplemental vitamin D and limited sun exposure.

Objective

Our goal was to determine the prevalence of vitamin D deficiency in this vulnerable population.

Setting and Participants

We enrolled 145 uninsured women at a County Free Medical Clinic in urban Michigan. Questionnaires were used to obtain information about demographics, medical history, vitamin supplementation, sunlight exposure, and dietary vitamin D intake.

Results

The 96 women who were tested for vitamin D status ranged in age from 21 to 65 years (mean 48 ± 11), and 67% were vitamin D deficient as indicated by a 25-hydroxyvitamin D [25(OH)D)] level <50 nmol/L (20 ng/mL). Non-Caucasians were 3 times more likely than Caucasians to be vitamin D deficient (P = .049). Mean dietary vitamin D intake was low (125 ± 109 IU/d) and only 24% of the participants used any supplemental vitamin D. Participants with total vitamin D intake <400 IU/day from diet and supplements were 10 times more likely to be vitamin D deficient than others (P < .001).

Conclusions

These results demonstrate a high prevalence of vitamin D deficiency in an uninsured, medically underserved female population. Uninsured women should be strongly encouraged to increase their vitamin D intake.

Background

Accumulating evidence suggests an increased prevalence of vitamin D deficiency in the Middle East. In this context, we aimed to determine whether the prevalence of vitamin D deficiency is related to degree of physical activity and sun exposure among apparently healthy Saudi children and adolescents, a little studied population.

Methods

A total of 331 Saudi children aged 6–17 years (153 boys and 178 girls) were included in this cross sectional study. Levels of physical activity and sun exposure were determined using a standard questionnaire. Anthropometry, serum calcium and 25-(OH) vitamin D were analyzed.

Results

All subjects were vitamin D deficient, the majority being moderately deficient (71.6%). Age was the single most significant predictor affecting 25 (OH) Vitamin D levels, explaining 21% of the variance perceived (p = 1.68 x 10-14). Age-matched comparisons revealed that for groups having the same amount of sun exposure, those with moderate or are physically active will have higher levels of vitamin D status, though levels in across groups remained deficient.

Conclusion

Vitamin D deficiency is common among Saudi children and adolescents, and is influenced by both sun exposure and physical activity. Promotion of an active outdoor lifestyle among Saudi children in both homes and schools may counteract the vitamin D deficiency epidemic in this vulnerable population. Vitamin D supplementation is suggested in all groups, including those with the highest sun exposure and physical activity.

AIM—To describe 21 cases of symptomatic rickets in adolescents.
METHODS—The setting was a primary and secondary care hospital in Saudi Arabia providing medical care to Saudi Arab company employees and their families. Cases of symptomatic rickets diagnosed between January 1996 and December 1997 in adolescents aged 10 to 15 years were assessed with respect to clinical presentation, biochemical and radiological evaluation, dietary assessment, and estimation of sun exposure.
RESULTS—Symptomatic rickets developed in 21 adolescents (20 females), with a prevalence rate of 68 per 100 000 children years. Presentation included carpopedal spasms (n = 12), diffuse limb pains (n = 6), lower limbs deformities (n = 2), and generalised weakness (n = 1). Biochemical findings included hypocalcaemia (n = 19), hypophosphoraemia (n = 9), raised serum alkaline phosphatase (n = 21) and parathormone (n = 7), and reduced 25-hydroxyvitamin D concentrations (n = 7). Radiological studies were suggestive of rickets in only eight children. All children had an inadequate dietary calcium and vitamin D intake. All but one had less than 60 minutes sun exposure per day.
CONCLUSION—Even in sunny climates, adolescents, especially females, can be at risk of rickets. Hypocalcaemic tetany and limb pains were the most common presenting symptoms. Radiological evidence was not present in every case.



The epidemic scourge of rickets in the 19th century was caused by vitamin D deficiency due to inadequate sun exposure and resulted in growth retardation, muscle weakness, skeletal deformities, hypocalcemia, tetany, and seizures. The encouragement of sensible sun exposure and the fortification of milk with vitamin D resulted in almost complete eradication of the disease. Vitamin D (where D represents D2 or D3) is biologically inert and metabolized in the liver to 25-hydroxyvitamin D [25(OH)D], the major circulating form of vitamin D that is used to determine vitamin D status. 25(OH)D is activated in the kidneys to 1,25-dihydroxyvitamin D [1,25(OH)2D], which regulates calcium, phosphorus, and bone metabolism. Vitamin D deficiency has again become an epidemic in children, and rickets has become a global health issue. In addition to vitamin D deficiency, calcium deficiency and acquired and inherited disorders of vitamin D, calcium, and phosphorus metabolism cause rickets. This review summarizes the role of vitamin D in the prevention of rickets and its importance in the overall health and welfare of infants and children.

A disruption in any part of the vitamin D physiological pathway can result in vitamin D deficiency, which may lead to bone pain, muscle weakness, falls, low bone mass, and fractures. Recognizing the signs and symptoms helps physicians make a proper diagnosis and prescribe appropriate treatment. Physicians should suspect osteomalacia in patients who have prolonged vitamin D deficiency, a low serum calcium level, or a low serum phosphorus level. Patients with cystic fibrosis are at increased risk for deficiencies in fat-soluble vitamins, including vitamin D. Secondary hyperparathyroidism can develop in patients with chronic kidney disease as a result of low 25-hydroxyvitamin D levels or impaired conversion to 1,25-dihydroxyvitamin D. Patients may experience abnormal vitamin D metabolism as a result of taking anticonvulsants and other medications.

Children with calcium-deficiency rickets may have increased vitamin D requirements and respond differently to vitamin D2 and vitamin D3. Our objective was to compare the metabolism of vitamins D2 and D3 in rachitic and control children. We administered an oral single dose of vitamin D2 or D3 of 1.25 mg to 49 Nigerian children—28 with active rickets and 21 healthy controls. The primary outcome measure was the incremental change in vitamin D metabolites. Baseline serum 25-hydroxyvitamin D [25(OH)D] concentrations ranged from 7 to 24 and 15 to 34 ng/mL in rachitic and control children, respectively (p < .001), whereas baseline 1,25-dihydroxyvitamin D [1,25(OH)2D] values (mean ± SD) were 224 ± 72 and 121 ± 34 pg/mL, respectively (p < .001), and baseline 24,25-dihydroxyvitamin D [24,25(OH)2D] values were 1.13 ± 0.59 and 4.03 ± 1.33 ng/mL, respectively (p < .001). The peak increment in 25(OH)D was on day 3 and was similar with vitamins D2 and D3 in children with rickets (29 ± 17 and 25 ± 11 ng/mL, respectively) and in control children (33 ± 13 and 31 ± 16 ng/mL, respectively). 1,25(OH)2D rose significantly (p < .001) and similarly (p = .18) on day 3 by 166 ± 80 and 209 ± 83 pg/mL after vitamin D2 and D3 administration, respectively, in children with rickets. By contrast, control children had no significant increase in 1,25(OH)2D (19 ± 28 and 16 ± 38 pg/mL after vitamin D2 and D3 administration, respectively). We conclude that in the short term, vitamins D2 and D3 similarly increase serum 25(OH)D concentrations in rachitic and healthy children. A marked increase in 1,25(OH)2D in response to vitamin D distinguishes children with putative dietary calcium-deficiency rickets from healthy children, consistent with increased vitamin D requirements in children with calcium-deficiency rickets. © 2010 American Society for Bone and Mineral Research.

Background

Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.

Methods

552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.

Results

The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.

Conclusion

Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy.

Background:

Inadequate levels of vitamin D increase the risk of osteoporosis, a highly prevalent condition in patients with traumatic spinal cord injury (SCI). Reduced sunlight and dark skin further contribute to low vitamin D levels.

Objectives:

To compare serum 25-hydroxy vitamin D [vitamin D25(OH)] levels in acute and chronic SCI and to explore seasonal and ethnic differences among patients with acute and chronic SCI.

Patients/Methods:

Patients (N  =  96) aged 19 to 55 years with C3-T10 motor complete SCI participated. Acute SCI was 2 to 6 months after injury, whereas chronic SCI was at least 1 year from injury. Serum vitamin D25(OH), calcium, and parathyroid hormone were drawn during summer or winter months. Vitamin D deficiency (<13 ng/mL), insufficiency (<20 ng/mL), and subtherapeutic (<32 ng/mL) levels were compared for all groups. A 3-way analysis of covariance was adopted to determine significant main effects of season, chronicity, and ethnicity. Interactions between season and chronicity, season and ethnicity, and chronicity and ethnicity were evaluated. Evaluation of a 3-way interaction among season, chronicity, and ethnicity was completed.

Results:

In summer, 65% of patients with acute SCI and 81% of patients with chronic SCI had subtherapeutic vitamin D levels, whereas in winter, 84% with acute SCI and 96% with chronic SCI had vitamin D25(OH) (<32ng/mL). Lower vitamin D25(OH) levels were observed in African Americans relative to whites. Significant main effects were noted for season (P  =  0.017), chronicity (P  =  0.003), and ethnicity (P < 0.001). However, interactions between 2 or more factors were not found.

Conclusions:

Vitamin D insufficiency and deficiency are found in the majority of patients with chronic SCI and in many with acute SCI. Initial screening for serum vitamin D25(OH) levels should be performed early in rehabilitation. Periodic monitoring in the chronic setting is highly recommended.