Rickets: an old form for a new century

Non-Musculoskeletal Benefits of Vitamin D beyond the Musculoskeletal System

Vitamin D, a fat-soluble prohormone, is endogenously synthesized in response to sunlight or taken from dietary supplements. Since vitamin D receptors are present in most tissues and cells in the body, the mounting understanding of the role of vitamin D in humans indicates that it does not only play an important role in the musculoskeletal system, but has beneficial effects elsewhere as well. This review summarizes the metabolism of vitamin D, the research regarding the possible risk factors leading to vitamin D deficiency, and the relationships between vitamin D deficiency and numerous illnesses, including rickets, osteoporosis and osteomalacia, muscle weakness and falls, autoimmune disorders, infectious diseases, cardiovascular diseases (CVDs), cancers, and neurological disorders. The system-wide effects of vitamin D and the mechanisms of the diseases are also discussed. Although accumulating evidence supports associations of vitamin D deficiency with physical and mental disorders and beneficial effects of vitamin D with health maintenance and disease prevention, there continue to be controversies over the beneficial effects of vitamin D. Thus, more well-designed and statistically powered trials are required to enable the assessment of vitamin D’s role in optimizing health and preventing disease.

An investigation of vitamin D deficiency in pregnant women and their infants in Giresun province located in the Black Sea region of Turkey

The aim of this study is to investigate vitamin D deficiency and the associated risk factors in pregnant women and their infants in the Black Sea region of Turkey. One hundred and twenty healthy pregnant women in the last trimester and their healthy newborn pairs were observed between June and August 2017 in Giresun province. The serum 25(OH)D3 and calcium levels were measured through the samples collected from maternal and neonatal cord blood. The effects of maternal lifestyle on the maternal vitamin D levels were assessed by multiple regression analysis. The mean concentrations of 25(OH)D3 were found to be 9.54 ± 6.35 ng/mL and 11.16 ± 6.52 ng/mL in the maternal and neonatal cord blood sera, respectively. Vitamin D deficiency (≤20 ng/mL) and severe vitamin D deficiency (≤5 ng/mL) were observed in between 94.2% and 24.2% of mothers and 90% and 10% of infants, respectively. The clothing style, the consumption of milk/dairy products and antenatal multivitamin supplement usage were found as significant factors on the serum vitamin D levels. Even during the Summer months, the vitamin D deficiency in mothers and infants was observed at high rates in the Eastern Black Sea region of Turkey. As a result, it has been concluded that routine maternal serum 25(OH)D3 measurements for clinical follow-up, vitamin D supplementation and regular consumption of dairy products should be recommended. Impact Statement What is already known on this subject? Vitamin D deficiency is a very important risk factor to be considered for maternal and infant health. In a large number of studies, it has been observed that the risk of a vitamin D deficiency in women during their pregnancy was found to be higher, depending on the various strong influences such as the demographic and maternal lifestyles. What the results of this study add? A vitamin D deficiency associated with the demographic and lifestyle factors of pregnant women and their infants was investigated in Giresun province, located in the Eastern Black Sea region of Turkey. The results of this study add that a vitamin D deficiency in the maternal and in the infants may be observed at high rates in regions with mostly rainy weather, even during the Summer months. What the implications are of these findings for clinical practice and/or further research? The vitamin D levels in infants can be determined indirectly by looking at the vitamin D levels in third trimester pregnancies. Furthermore, it is suggested as a non-invasive method to determine vitamin D levels by taking advantage of the maternal level, without measuring the vitamin D levels of infants. Thus, this will be effective to reduce health costs and to prevent the possible diseases affecting the future life of infants. Routine maternal serum 25(OH)D3 measurements for clinical follow-up, vitamin D supplementation and the regular consumption of dairy products should be recommended to pregnant women with risk factors, even in the Summer in the Black Sea Region of Turkey. In addition, further studies are needed to investigate the vitamin D deficiency associated with the demographic and lifestyle factors of pregnant women and their infants, especially for the different locations of Turkey.

Vitamin D deficiency in mothers, neonates and children

Vitamin D is produced in response to the exposure of skin to sunlight through UV-B synthesis. It can also be obtained from diet and dietary supplements. Vitamin D is essential for strong bones as it helps to absorb calcium from diet. Vitamin D deficiency mainly occurs if strict vegetarian diet is followed as mostly the source of vitamin D is animal based; therefore, exposure to sunlight is restricted or having dark skin color. Low vitamin D levels results in increased possibility of gestational diabetes among pregnant women, low birth weight and pre-eclampsia in infants, and mothers may suffer bone impairment, osteoporosis, hypocalcaemia, and hypertension. Vitamin D deficiency is directly linked with severe complication in mothers and neonates, causing rickets, poor fetal growth and infantile eczema in neonates. Higher prevalence rate of vitamin D deficiency has led professionals to emphasize on development of relevant precautionary measures.

Etiologic risk factors and vitamin D receptor gene polymorphisms in under one-year-old infants with urolithiasis

The incidence of urinary tract stones in infancy has been increasing in Turkey. Risk factors and vitamin D receptor (VDR) gene polymorphisms were investigated in infants aged < 1 year who had stones. Forty infants with urinary tract stones and 80 infants without stones, aged < 1 year were enrolled in this study. Detailed surveys were taken of all infants, metabolic parameters and ApaI and FokI VDR gene polymorphisms were investigated. Infants with stones tended to be more commonly fed formula and multivitamins (vitamins A, C, D) (p < 0.05). Positive family history came into prominence in the stony group (p < 0.05). There were no significant differences in ApaI and FokI VDR gene polymorphisms between the groups with stones and the control groups. However, CA genotype of ApaI polymorphism was associated with family history and C allele of ApaI was related with family history and hypercalciuria (p < 0.05). Hypercalciuria emerged as an underlying metabolic abnormality in the etiology of stones, and was observed at a rate of 38%. Infants who are given formula and multivitamins for vitamin D supplementation are at increased risk for the formation of urinary tract stones. VDR gene polymorphisms cause the formation of urinary tract stones and affect calcium (Ca) metabolism.

Formulation characteristics of triacylglycerol oil-in-water emulsions loaded with ergocalciferol using microchannel emulsification

Food grade monodisperse O/W emulsions encapsulating ergocalciferol have been formulated using microchannel emulsification. The O/W emulsion droplets have an encapsulation efficiency of over 75% within the evaluated storage period.

Rickets: Part I

Rickets is characterized by impaired mineralization and ossification of the growth plates of growing children caused by a variety of disorders, the most frequent of which is nutritional deficiency of vitamin D. Despite ample knowledge of its etiology and the availability of cost-effective methods of preventing it, vitamin D deficiency rickets remains a significant problem in developing and developed countries. This two-part review covers the history, etiology, pathophysiology and clinical and radiographical findings of vitamin D deficiency rickets. Other less frequent causes of rickets and some of the disorders entering into the differential diagnoses of rickets are also considered. Controversial issues surrounding vitamin D deficiency include determination of what constitutes vitamin D sufficiency and the potential relationship between low levels of vitamin D metabolites in many individuals and unexplained fractures in infants.

Vitamin D and metabolism: facts, myths and misconceptions

Vitamin D is essential for a vast number of physiologic processes, and thus adequate levels are necessary for optimal health. During childhood and adolescence, an adequate vitamin D status is needed due to its important role in cell growth, skeletal development and growth. Vitamin D is a fat-soluble vitamin that is naturally found in very few foods, is added to others, and is available as a dietary supplement. It is produced endogenously when ultraviolet light strikes the skin. The adequate intake and status of vitamin D greatly depends on age, concomitant diseases and the use of some medications that are covered in-depth in the article. Recent epidemiologic and experimental evidence has suggested that low vitamin D concentrations seem to be significantly associated with all-cause mortality, cardiovascular disease, cancer (mainly breast, prostate and colorectal), hypertension, metabolic syndrome, diabetes mellitus type 1 and type 2. However, the data supporting protective effects of vitamin D supplementation on conditions other than skeletal diseases like rickets, osteoporosis and osteomalacia are very weak, and the large, controlled clinical trials that are in progress now should resolve this issue.

Vitamin D deficiency in pregnant women and their neonates in spring time in western Turkey

Although Turkey is located in a sunny region, vitamin D deficiency is still a serious health problem in pregnant women and their infants, especially among the low socio-economic status Turkish population. This study was carried out in order to measure serum 25-hydroxyvitamin D3 [25(OH)D] concentrations of the pregnant women in the last trimester and in their neonates at delivery and to determine the factors associated with maternal serum 25(OH)D concentrations. Among the patients visiting the Ege Obstetrics and Gynecology Hospital in the period March to May 2008, 258 healthy pregnant women ≥37 weeks of gestation were included in this study. The information on different characteristics such as the number of pregnancies and births, nutritional status, vitamin and mineral support during gestation, educational status, clothing style and the economic level of the family was collected from women. Blood samples from the mothers and umbilical cord of the newborns were taken to measure 25(OH)D. The mean 25(OH)D concentrations of the mothers and their infants were 11.5 ± 5.4 ng/mL and 11.5 ± 6.8 ng/mL, respectively. We found a strong positive correlation between maternal serum and umbilical cord blood 25(OH)D concentrations (r = 0.651, P < 0.001). The concentration of 25(OH)D was ≤20 ng/mL in 233 mothers (90.3%) and ≤10 ng/mL in 130 mothers (50.4%). Maternal serum 25(OH)D concentrations related strongly to factors such as uncovered dressing style, sufficient consumption of dairy products and multivitamin use during gestation (P < 0.05). About half (52.7%) of these women had a covered dressing style. 25(OH)D concentrations of these covered dressing mothers and their infants were 9.7 ± 5.1 ng/mL and 9.7 ± 5.6 ng/mL, respectively, which were significantly lower compared with those of uncovered mothers and their babies (P < 0.001). This study showed that, despite a sunny environment, vitamin D deficiency and insufficiency are highly prevalent among the mothers and their neonates. This is generally due to the life style and nutritional status of the mothers. These findings suggest that much more effective vitamin D prophylaxis programmes should be implemented for pregnant women as well as for their babies.

Evaluation of children with nutritional rickets

AIM

To evaluate the clinical findings, risk factors, therapy and outcome in 946 children with nutritional rickets.

PATIENTS AND METHODS

This retrospective study included a review of medical records of patients with nutritional rickets between March 2004 and 2009. Patients who displayed both the biochemical inclusion criteria and the clinical signs/symptoms or radiological signs of rickets were included in the study.

RESULTS

The present study included 946 patients aged between 4 months and 15 years. Distribution of the cases showed a density between December and May. The age at diagnosis, showed two peaks and most of the patients were in the age range 0-23 months and 12.0-15 years. In infants and young children, most of the patients had been admitted to the hospital due to infectious diseases. In older children, short stature and obesity were the most common complaints.

CONCLUSION

Children aged between 0-23 months and 12.0-15 years were under most risk for nutritional rickets, especially in winter and spring and vitamin D should be given to them as supplementation dose.

Vitamin D metabolism and rickets in domestic animals: a review

Rickets and osteomalacia are increasing in prevalence in people because of cultural practices, breast-feeding, decreased sun exposure, and increased sunscreen usage. Several hereditary forms of rickets owing to either renal phosphate wasting or defects in vitamin D metabolism are also reported in people. Rickets is well recognized in domestic animals, but published reports are not always supported by microscopic findings, and diagnoses based on clinical signs and radiology are unreliable. Most cases in domestic animals are caused by dietary deficiency of either vitamin D or phosphorus, but occasional inherited forms are reported in pigs, sheep, cats, and dogs. There is variation between species in susceptibility to dietary vitamin D and phosphorus deficiency and in the ability to manufacture vitamin D in their skin. A number of mouse models have been discovered or created to study human skeletal diseases and skeletal homeostasis. With the discovery that vitamin D is involved in not only calcium and phosphorus homeostasis but also in the immune system and cancer, there is great potential for new and existing animal models to generate valuable information about vitamin D and its many functions. This review presents an overview of vitamin D metabolism and rickets in domestic and laboratory animals and makes comparisons where appropriate with the disease in humans.

Nutritional rickets and z scores for height in the United Arab Emirates: to D or not to D?

BACKGROUND

Vitamin D deficiency is still prevalent worldwide, including the Middle East. A cohort of patients with nutritional rickets was treated with vitamin D(2) (ergocalciferol) alone. After this intervention, patients were followed to document changes in z scores for height after treatment. The secondary aim was to determine the proportion of affected children who had vitamin D deficiency or calcium deficiency.

METHODS

Z score for height was calculated as the difference between the observed value and the median value, divided by the SD of the population. Z scores were compared in patients before and after treatment.

RESULTS

The improvement in z score after treatment was 0.86 +/- 0.95. The 95% confidence interval for the mean difference was 1.32-0.40 (t = 3.95, P < 0.001). With a diagnostic cut-off for 25 hydroxyvitamin D(3) (25D) deficiency of <25 nmol/L, only half were diagnosed with severe vitamin D deficiency. The remaining patients had presumable calcium deficiency. The alkaline phosphatase (ALP) was negatively correlated to z scores, implying that higher ALP concentrations predicted severe bone disease (lower z scores). The variables 25D and age were moderately and positively correlated (Pearson's r = 0.59, 95%CI: 0.15-0.84; P = 0.01), indicating that younger infants had the lowest 25D levels.

CONCLUSION

Vitamin D alone was efficient in resolving radiological and biochemical disturbances as well as improving z scores for height in a cohort of children with nutritional rickets, which included patients with 25D deficiency as well as calcium deficiency. The results support the hypothesis of the interplay and continuum of 25D deficiency and calcium deficiency in the pathogenesis of rickets.