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.

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.

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.

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.

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.

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.

Nutritional rickets among breast-fed black and Alaska Native children.

Although nutritional rickets remains a problem primarily in developing countries, children in northern climates in developed countries may also be at risk. We reviewed the case histories of five children diagnosed in Alaska during 1993-96. Three of the children were black and two Alaska Native. Their ages ranged from 11 to 20 months and they presented during January, April, and September. All of the children were breast-fed but only two received their milk intake exclusively from breast milk. The presenting complaint included abnormal gait in two children and seizures, bowed legs, and growth delay in one child each. All five children demonstrated a decrease in their height-for-age percentile. The most common physical finding was a rachitic rosary which was present in four children. In Alaska, all black and Alaska Native children (and other more pigmented children) less than two years of age who receive all or part of their milk intake from breast milk should receive vitamin D supplementation regardless of the time of year.

[Nutritional rickets--an old disease with new relevance]. / Alimentaer rakitt. En gammel sykdom med ny aktualitet.

Rickets caused by poor nutrition was widespread in Norway at the beginning of this century. Today it is a very rare disease among Norwegian children. During the last 20 years, however, it has become quite common among immigrant children who have come from developing countries to live in Norway. This is probably due to a combination of different factors such as material vitamin D deficiency, lack of vitamin D supplementation, long-lasting breast feeding, latitude (therefore little sunshine in winter) and lack of exposure to sunshine during the summer. The paper reviews the disease, with a special emphasis on clinical findings, diagnosis, treatment and prevention.

Persistence of Vitamin D-deficiency rickets in Toronto in the 1990s.

To assess the current picture of vitamin D deficiency, we reviewed all 17 cases of vitamin D-deficiency rikets seen in the referral clinic of a children's hospital in Toronto between 1988 and 1993. The diagnosis was made at 7 to 33 months of age. All the children were symptomatic all had biochemical and radiographic abnormalities, two suffered hypocalcemic seizures, and all had bowing of the extremities. Twelve of the children were born to parents who were recent immigrants to Canada. All were of Asian or African origin with dark skin. All the children had been exclusively breastfed with no vitamin D supplementation, and had had little or no sunlight exposure. All the patients responded to vitamin D therapy. We conclude that vitamin D-deficiency rickets remains an environmental/nutritional deficiency disease in this city and that efforts at prevention should target children with pigmented skin from families who are recent immigrants.