Micro-CT assessment of dental mineralization defects indicative of vitamin D deficiency in two 17th-19th century Dutch communities.

OBJECTIVES: This study investigates vitamin D deficiency patterns in individuals from birth to the beginning of adolescence. Microscopic computed tomography (micro-CT) evaluation of interglobular dentine (IGD) in teeth provides information on the age of disease onset and the number of deficient periods per individual, which will increase our understanding of factors influencing vitamin D deficiency prevalence, including sociocultural practices and latitude. MATERIALS AND METHODS: Beemster and Hattem, two Dutch 17th-19th century communities, yielded relatively high prevalences of rickets (15-24%) and residual rickets (15-24%). From the affected individuals, a subsample of 20 teeth were selected for micro-CT scanning. Thin sections were made of 17 teeth, consisting of 6 teeth with and 11 teeth without observable IGD on micro-CT that were included for method comparison. RESULTS: About 19 out of 29 (65.5%) individuals (one tooth was deemed unobservable) presented with IGD on micro-CT. Eight of the 11 (72.7%) individuals without IGD on micro-CT demonstrated histologically visible IGD. In 40.7% (11/27) of the affected individuals (combined micro-CT and histology results), vitamin D deficiency was recurrent, and in four individuals, some episodes occurred at approximately annual intervals suggesting vitamin D deficiency was seasonal. In three individuals, IGD occurred in the dentine formed around birth, suggesting maternal vitamin D deficiency. DISCUSSION: Micro-CT analysis of IGD is found to be a valuable non-destructive method that can improve our understanding of the influence of sociocultural practices and latitude on disease development within age and sex groups in past communities.

Cardiac, bone and growth plate manifestations in hypocalcemic infants: revealing the hidden body of the vitamin D deficiency iceberg.

BACKGROUND: Whilst hypocalcemic complications from vitamin D deficiency are considered rare in high-income countries, they are highly prevalent among Black, Asian and Minority Ethnic (BAME) group with darker skin. To date, the extent of osteomalacia in such infants and their family members is unknown. Our aim was to investigate clinical, cardiac and bone histomorphometric characteristics, bone matrix mineralization in affected infants and to test family members for biochemical evidence of osteomalacia. CASE PRESENTATION: Three infants of BAME origin (aged 5-6 months) presented acutely in early-spring with cardiac arrest, respiratory arrest following seizure or severe respiratory distress, with profound hypocalcemia (serum calcium 1.22-1.96 mmol/L). All infants had dark skin and vitamin D supplementation had not been addressed during child surveillance visits. All three had severely dilated left ventricles (z-scores + 4.6 to + 6.5) with reduced ejection fraction (25-30%; normal 55-70), fractional shortening (7 to 15%; normal 29-40) and global hypokinesia, confirming hypocalcemic dilated cardiomyopathy. They all had low serum levels of 25 hydroxyvitamin D (25OHD < 15 nmol/L), and elevated parathyroid hormone (PTH; 219-482 ng/L) and alkaline phosphatase (ALP; 802-1123 IU/L), with undiagnosed rickets on radiographs. One infant died from cardiac arrest. At post-mortem examination, his growth plate showed a widened, irregular zone of hypertrophic chondrocytes. Histomorphometry and backscattered electron microscopy of a trans-iliac bone biopsy sample revealed increased osteoid thickness (+ 262% of normal) and osteoid volume/bone volume (+ 1573%), and extremely low bone mineralization density. Five of the nine tested family members had vitamin D deficiency (25OHD < 30 nmol/L), three had insufficiency (< 50 nmol/L) and 6/9 members had elevated PTH and ALP levels. CONCLUSIONS: The severe, hidden, cardiac and bone pathology described here exposes a failure of public health prevention programs, as complications from vitamin D deficiency are entirely preventable by routine supplementation. The family investigations demonstrate widespread deficiency and undiagnosed osteomalacia in ethnic risk groups and call for protective legislation.

Assessment of Vitamin D Status and Response to Vitamin D3 in Obese and Non-Obese Iranian Children.

BACKGROUND: Obesity seems to be a critical issue nowadays because of its high prevalence and its adverse effects on health. There is some evidence indicating the relationship between obesity and lower serum 25-hydroxyvitamin D [25(OH)D] concentration. The aim of the present study was to examine serum 25(OH)D status of obese and non-obese Iranian children and compare their therapeutic response with identical oral vitamin D3 treatment. METHODS: In a non-randomized clinical trial, serum 25(OH)D level of 45 obese and 45 non-obese Iranian children aged 2-14 years was measured. Those with serum 25(OH)D status <30 ng/ml (73 cases) were treated with one pearl of vitamin D3 (50 000 International Units) once a week for 6 weeks. Serum vitamin D was measured once more 2 weeks after treatment. RESULTS: The frequency of hypovitaminosis D was 43/45 (95.6%) in obese and 30/45 (66.7%) in non-obese children at baseline (p < 0.001). After treatment of 73 cases (43 obese, 30 non-obese), the above percentages were decreased to 24/43 (55.8%) and 1/30 (3.3%), respectively (p < 0.001). CONCLUSION: Our study demonstrated a high frequency of vitamin D deficiency among Iranian children, particularly the obese ones. Moreover, low therapeutic response in the obese group is witnessed.

Role of calcium deficiency in development of nutritional rickets in Indian children: a case control study.

CONTEXT: Nutritional rickets is usually attributed to vitamin D deficiency. Studies from some tropical countries have postulated low dietary intake of calcium as the cause of nutritional rickets. Both vitamin D and dietary calcium deficiency are highly prevalent in India. Information on their relative contribution in the development of rickets in Indian children is limited. OBJECTIVE: The aim was to study the role of calcium and vitamin D deficiency in causation of nutritional rickets in young Indian children. DESIGN AND METHODS: In a case-control study, 67 children with nutritional rickets and 68 age- and sex-matched healthy controls were compared for demographic factors, nutritional status, sun exposure (UV score), dietary calcium and phytate intake (for subjects not breast-fed at presentation), and biochemical parameters [serum calcium, inorganic phosphate, alkaline phosphatase, 25-hydroxyvitamin D (25OHD), and PTH]. RESULTS: Mean intake of calcium (204±129 vs. 453±234 mg/d; P<0.001) and proportion of calcium from dairy sources (41.7 vs. 88.6%; P<0.001) were significantly lower in cases vs. controls. The dietary intake of phytate was also significantly higher in cases (P=0.01). Median serum 25OHD level (interquartile range) in both cases and controls was in the range of deficiency [13.7 (10; 17.9) and 19.4 (12.3; 24.6) ng/ml, respectively]. There was no significant difference in the serum 25OHD level (P=0.08) or sun exposure as measured by UV score (P=0.39) among the cases and controls. In cases with rickets, significant negative correlations were seen between dietary calcium intake and radiological score (r=-0.28; P=0.03) and PTH (r=-0.26; P=0.02). No correlation was found between serum 25OHD level and radiological score or biochemical parameters of rickets. CONCLUSIONS: Rickets develops when low dietary calcium intake coexists with a low or borderline vitamin D nutrition status.

The medicalization of sunlight in the early twentieth century.

This paper traces the emergence of the therapeutic use of sunlight in medicine during the first half of the twentieth century. This was a period of considerable flux in medicine with various strands of practice and theory competing. Drawing on two case studies of sunlight therapy, both artificial (actinotherapy) and natural (heliotherapy), in the treatment of rickets and tuberculosis this paper will explore how medicine was constituted within these regimes. The paper will argue that therapeutic and clinical applications of sunlight helped establish an association between sunlight and health but also defined a particular and specific performance of medicine.

[Severe vitamin D deficiency in children born in Denmark of dark-skinned women]. / Svær D-vitamin-mangel hos børn født i Danmark af kvinder med mørk hud.

Rickets due to malnutrition is rare in Denmark. The Danish Board of Health recommend that: pregnant women are treated with a daily dose of vitamin D daily (10 micrograms); emigrants with coloured skin have their vitamin D level assessed during pregnancy; all children receive a daily dose of vitamin D (10 micrograms) until two years old. Despite of these recommendations two cases of severe nutritional rickets among children of emigrants were discovered upon hospital admission. The symptoms were heterogeneous: delayed walking skills and convulsions. We conclude that nutritional rickets is a tricky diagnosis, but is preventable.

The presentation of rickets to orthopaedic clinics: return of the English disease.

Rickets is a potentially treatable disease of the bone that is most commonly due to deficiency of vitamin D and is increasing in incidence in developed countries. Risk factors include dietary factors, the practice of covering up and darker skin pigmentation. This small retrospective case study set out to examine all cases of rickets presenting to the Paediatric Orthopaedic clinic over a 15-month period. Rickets presented in a bimodal fashion in the 6 cases identified: in males and females aged 3 or less and female adolescents aged 10 and above. This is in keeping with what is known regarding the rapid phases of growth during development. Five cases were from ethnic minority groups. Both female adolescents presented with genu valgum. Rickets can present primarily to Orthopaedic clinics with vague musculoskeletal symptoms. We recommend that biochemical screening be performed on patients from ethnic minorities who may be 'at risk'.

Doing the month: rickets and post-partum convalescence in rural China.

OBJECTIVE: to analyse the health beliefs underlying the Chinese custom of 'doing the month', in particular mothers' perceptions of rickets. DESIGN: a qualitative approach was used. Four focus group discussions were tape recorded. Translated transcripts were analysed and coded. SETTING: Yuci District, rural Shanxi Province, China. PARTICIPANTS: eighteen young mothers with children aged between 12 and 24 months, five grandmothers aged between 48 and 55 years, five township clinic maternal and child health workers, and seven traditional medicine doctors. FINDINGS: Zuo yuezi (doing the month) is accepted by Chinese mothers as a time of respite and physical recovery. It is also burdensome to mothers, as cloistering indoors compromises both mother and baby's exposure to the sun, resulting in vitamin D deficiency and rickets. KEY CONCLUSIONS: in order to reduce the rates of rickets in children, it is important to promote a more balanced and health-enhancing form of zuo yuezi that maintains necessary vitamin D status of both the mother and her baby. By understanding this custom, medical professionals caring for pregnant and post-partum Chinese women in Western countries will be able to better serve their health needs.

Nutritional rickets in Denmark: a retrospective review of children's medical records from 1985 to 2005.

INTRODUCTION: This study describes clinical and biochemical characteristics of nutritional rickets and risk factors at diagnosis among children living in Denmark. All medical records from patients with rickets referred to or discharged from hospitals in Southern Denmark from 1985 to 2005 were identified by register search. MATERIALS AND METHODS: Patients included were younger than 15 years of age and fulfilled the diagnostic criteria of primary, nutritional rickets. A total of 112 patients with nutritional rickets were included: 29 were of ethnic Danish origin, and 83 were immigrants. RESULTS: Patients diagnosed before the age of 4 (median 1.4) years displayed the classic clinical signs of rickets, whereas patients diagnosed after the age of 4 (median 12.5) years had few clinical signs and unspecific symptoms. Ethnic Danish patients were only diagnosed before age 24 months, and they accounted for 73% of all cases presenting with hypocalcemic seizures, but biochemically, they did not have more severe rickets. Of patients diagnosed before the age of 4 years, 45% were ethnic Danish. In early childhood, insufficient or no vitamin D supplementation was given in 88% of all cases. Among immigrant girls older than 4 years of age, 78% were veiled. DISCUSSION: Nutritional rickets in Denmark is predominantly a disease among immigrants, but ethnic Danish patients comprised nearly half of all patients diagnosed before the age of 4 years, and they presented more frequently with hypocalcemic seizures. The main risk factors were omitted, such as vitamin D prophylaxis among the youngest patients and veiling among older children/teenagers.

Higher prevalence of vitamin D deficiency in mothers of rachitic than nonrachitic children.

Vitamin D deficiency [serum 25-hydroxyvitamin D <25 nmol/L (<10 ng/mL)] was identified in 92% of rachitic Arab children and 97% of their mothers compared with 22% of nonrachitic children and 52% of their mothers. There was a positive correlation between maternal and child vitamin D levels. We conclude that mothers of rachitic children should be investigated and treated for vitamin D deficiency.

Rickets in the Dairy State.

BACKGROUND: Nutritional vitamin D deficiency rickets occurs when children do not receive adequate vitamin D, which can be obtained from diet or manufactured in the skin when there is adequate sun exposure. A number of reports have described cases of vitamin D deficiency rickets in breastfed infants, but the public health significance of this problem in Wisconsin is unknown. OBJECTIVES: Our objectives were to identify cases of vitamin D deficiency rickets in Wisconsin infants and to determine the percentage of these infants participating in the Wisconsin Women, Infant and Children (WIC) program. METHODS: All cases of rickets due to nutritional vitamin D deficiency seen at Children's Hospital of Wisconsin or its associated outpatient clinics were identified by retrospective chart review. Data collected included date of birth, age at presentation, race, clinical presentation, diet history, history of vitamin supplementation, x-ray findings, and biochemical studies. The children with nutritional vitamin D deficiency rickets were cross-referenced with the Wisconsin WIC database. RESULTS: Fifty-one definite cases of nutritional vitamin D deficiency rickets were identified. Skeletal deformities, failure to thrive, fractures, seizures, incidental lab finding, tetany, and refusal to walk were the most common reasons for identifying rickets. All of the children were breastfed and did not receive vitamin supplementation. The infants had a mean age of 13.6 months and 46 (90%) were African American. Thirty-seven out of 51 children (73%) were enrolled in the Wisconsin WIC program. CONCLUSION: Vitamin D deficiency nutritional rickets is an important public health problem in Wisconsin. The Wisconsin WIC program may be an important site for intervention strategies.

[Rickets in Asian immigrants]. / Raquitismo carencial en inmigrantes asiáticos.

Although rickets is considered to have practically disappeared in developed countries, there is increasing evidence of widespread vitamin D deficiency among immigrants. Many studies report rickets and osteomalacia in Asian infants, adolescents and pregnant women moving to developed countries with a cooler climate. The etiopathogenesis of this disorder of calcium and D vitamin metabolism depend mainly on environmental and sociocultural factors, associated with low exposure to sunlight and low calcium intake, among other dietary factors. Given the recent increase in the number of immigrants to Spain, the prevention and treatment of this disease in Asian children and adolescents should be reviewed.

[Rickets in Asian immigrants during puberty]. / Raquitismo en inmigrantes asiáticos en período puberal.

Rickets usually occurs in the first two years of life and in puberty since metabolic demand is increased due to rapid growth in these two critical periods of life, when peak bone mass is achieved. Rickets remains one of the most prevalent pediatric diseases in developing countries. Although it is considered to have disappeared in developed countries, there is increasing evidence of widespread vitamin D deficiency among immigrants. There are many reports on rickets and osteomalacia in Asian infants, adolescents and pregnant women moving from India, Pakistan and Bangladesh to developed countries with a cooler climate. We describe three teenagers of Pakistani origin. Clinical presentation included limb pains, muscular weakness, knock-knees and seizures. In all three patients, biochemical findings included hypocalcemia, raised serum parathormone and alkaline phosphatase, and reduced 25-hydroxy vitamin D concentrations. After vitamin D treatment and dietary counseling, biochemical findings returned to normal and their symptoms improved. Given the recent increase in the number of immigrants to Spain, this forgotten disease will probably reappear.

[Severe rickets in puberty]. / Svaer rachitis i puberteten.

Two adolescent brothers of Palestinian origin are described. They had lived an extreme indoor life for years, had low vitamin D intake and hypocalcaemia. Despite longstanding disabling symptoms the diagnosis was delayed. It is emphasized that rickets should be considered in such patients.

Nutritional rickets still afflict children in north Texas.

Nutritional rickets is uncommon in North America, particularly in regions where sunlight is plentiful. Recent epidemics in North America occurred in dark-skinned toddlers with poor nutrition who had insufficient exposure to sunlight and whose parents were members of ethnic, social, and socioeconomic groups with predisposing practices. Nine children (8 toddlers and 1 infant) were referred to the Bone Metabolic Clinic at Texas Scottish Rite Hospital for suspected rickets between October 1997 and October 1998. The diagnosis of nutritional rickets was based on clinical, biochemical, and radiological evidence. All children were dark-skinned: 8 were African Americans and 1 was of Hispanic parentage. All children were breast-fed with minimal intake of dairy products; none received vitamin supplementation. All children were followed up by health care professionals. Two patients were children of upper-middle class parents. Birth order was not a contributing factor in the development of nutritional rickets. Radiological and biochemical rachitic changes remitted within 3 months of vitamin D therapy combined with dietary modification. Primary care providers should consider vitamin D supplementation in all infants with increased skin pigmentation and especially in those who are primarily breast-fed. Nutritional rickets can develop in dark-skinned infants of any social or ethnic background. Residing in a geographical area with abundant sunlight is not a guarantee against the development of nutritional rickets in dark-skinned children.