Nutritional rickets and osteomalacia in school children and adolescents

OBJECTIVE

To review experiences of nutritional rickets and osteomalacia in school children and adolescents at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia.

METHODS

Records of children and adolescents aged 6-18 years, seen at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, during the period January 1994 through to December 1999, who were diagnosed to have rickets or osteomalacia were reviewed. The diagnosis was based on clinical, biochemical and radiological data. Data extracted and analyzed included age, sex, presenting symptoms and signs, dietary history and sun exposure, blood count, bone profiles, renal and liver profile, and 25-hydroxy vitamin D3 and 1, 25 dihydroxy vitamin D3. Hand and wrist x-rays were carried out for all patients while bone density of lumbar spine and 3 femoral sites and bone scan were performed on the majority of patients.

RESULTS

Forty-two children and adolescents (25 females and 17 males) were diagnosed. Their age ranged between 6-18 years with a mean of 13.5. Non specific symptoms, such as bone pain and fatigue were the most presenting symptoms, while skeletal deformities and fractures were the presenting symptoms in only 5 and 3 patients. Lack of direct sun exposure and poor calcium intake was evident. Bone profiles at the time of diagnosis revealed mean serum calcium of 2.1 mmol/L, range 1.5 2.3 (Normal=2.2-2.7), phosphorus 1.1 mmol/L, range 0.7 1.9 (Normal=1.4 2.1) and alkaline phosphatase activities of 1,480 U/L, range 834-2,590 (N=<600). Serum concentrations of 25-hydroxy Vitamin D were low (<10 mg/L) while that of 1, 25 Dihydroxy Vitamin D varied between low to normal (<10-45 ng/L). Bone density of the lumbar spine and 3 femoral sites were performed in 26 patients and showed markedly reduced values, while bone scan demonstrated a high uptake of tracer throughout the skeleton "super scan". Multiple stress fractures were evident in 8 children.

CONCLUSION

Although a community-based study to assess the magnitude of the problem is needed, it seems that rickets and osteomalacia of nutritional origin are not that uncommon and deserves special attention from all pediatricians and practicing physicians. They also suggested that further studies are needed to help understand the pathophysiology, and identify the contributing factors for the development of the disorder.

Pathological long-bone fractures in residents with cerebral palsy in a long-term care facility in South Africa

A high incidence of long-bone fractures has been observed in children and young adults with quadriplegic cerebral palsy in residential care. This study aimed to determine factors that contribute to these fractures and to institute preventive treatment. Twenty individuals (12 males, eight females) of a cohort of 88 residents with spastic quadriplegia in residential care in Gauteng, South Africa who had sustained fractures were compared with a random sample of age-matched control participants (10 males, 10 females) from the same facility. Participants ranged in age from 6 to 29 years (median 17.5 years). The majority of fractures were in the upper extremities. There was radiological and biochemical evidence of rickets and osteomalacia in both groups. However, the severity of the disease was more pronounced in the group with fractures. There was a significant relation (p=0.002) between the number of fractures and the use of anticonvulsant therapy (ACT). Three months of vitamin D administration (calciferol 5000 iu/day) resulted in a marked clinical improvement. There were no fractures during this period in either group. In addition, the mean serum calcium (Ca) and phosphate (Pi) levels increased (Ca from 2.17 to 2.35 mmol/L and Pi from 1.13 to 1.66 mmol/L) and mean total alkaline phosphatase level decreased (from 1123 to 423 U/L). We concluded that vitamin D deficiency was the major factor contributing to the occurrence of fractures in this population. Unless sunlight exposure can be guaranteed, vitamin D supplementation should be considered for children and adults in residential care, especially if they are on ACT, even in areas with year-round sunshine.

Nutritional rickets in young Nigerian children in the Sahel savanna

OBJECTIVES

To determine the prevalence of clinical and biochemical rickets in an under-five out-patient population, relate the prevalence of biochemical rickets (BR) to the sociocultural characteristics of families and determine the response of nutritional rickets to vitamin D therapy.

DESIGN

Prospective cross-sectional and retrospective case-series surveys.

SETTING

Paediatric general out-patient and consultant clinics.

SUBJECTS

One hundred and ninety eight out-patients and twenty two patients aged >1 to 60 months treated for nutritional rickets.

INTERVENTIONS

Clinical examination, interview with mothers and determination of biochemical abnormalities of under-fives and management of patients with rickets using stosstherapy.

MAIN OUTCOME MEASURES

Prevalence of BR and response to stosstherapy.

RESULTS

Eight (4%) patients in the survey had clinical and biochemical rickets while 33 (17%) had biochemical rickets only; 92 (47%) other patients had isolated hypocalcaemia and/or hypophosphataemia. The prevalence of BR was higher in males (p <0.05), and increased with age (p <0.001). The prevalence was lower in families who were indigenous to the area (p <0.05), children of Moslem families (p <0.05) and children whose mothers were full-time housewives, unskilled or traders (p <0.01), and who lacked any formal western education (p = 0.157). Three of the seven evaluable patients who received stosstherapy responded late.

CONCLUSION

The results support the hypothesis that deficiency or reduced availability of dietary calcium may be of at least equal importance with vitamin D deficiency in the aetiology of nutritional rickets in the Sahel savanna.

Vitamin D deficiency in mothers of infants with rickets

OBJECTIVE

To identify infants treated for vitamin D deficiency rickets, and to determine the incidence of vitamin D deficiency in their mothers and their mothers' country of origin.

DESIGN

A retrospective audit of the medical records of children diagnosed with vitamin D deficiency rickets. Inpatients were identified by discharge diagnoses of vitamin D deficiency or hypocalcaemia and outpatients by pharmacy dispensing of cholecalciferol.

SETTING

The Women's and Children's Health Care Network and the Southern Health Care Network (Melbourne, VIC) from June 1994 to February 1999.

PATIENTS

55 children with vitamin D deficiency rickets.

RESULTS

Fifty-four of the 55 children were born to mothers with ethnocultural risk factors for vitamin D deficiency. Vitamin D status had been assessed in 31 of the 55 mothers (56%): 25 (81%) had 25-hydroxyvitamin D3 concentrations < or = 25 nmol/L, consistent with osteomalacia.

CONCLUSION

Vitamin D deficiency continues to occur in children of migrant families. When infants are diagnosed with vitamin D deficiency, vitamin D levels in their mothers and siblings should also be assessed.

Nutritional rickets in Georgia

Opinions expressed in commentaries are those of the authors and not necessarily those of the American Academy of Pediatrics or its Committees. Commentaries are not peer-reviewed.

Severe malnutrition among young children--Georgia, January 1997-June 1999

In October 1999, the Georgia Department of Human Resources (GDHR) was notified of two cases of severe malnutrition in toddlers. Both cases were associated with the use of commercial alternative milk. In response, GDHR and CDC reviewed Georgia hospital records to assess the frequency and cause of hospitalized cases of rickets and protein energy malnutrition (PEM). The findings of this review indicated that, although no new cases were associated with milk alternatives, three children had PEM and six had vitamin D deficiency rickets. The children with rickets had been breast fed for approximately 6 months while receiving no vitamin D supplementation. Rickets is preventable through the adequate intake of vitamin D. The American Academy of Pediatrics (AAP) is examining vitamin D supplementation among breast-fed infants.

Does ‘imprinting’ with low prenatal vitamin D contribute to the risk of various adult disorders?

Hypovitaminosis D is a candidate risk-modifying factor for a diverse range of disorders apart from rickets and osteoporosis. Based on epidemiology, and on in vitro and animal experiment, vitamin D has been linked to multiple sclerosis, certain cancers (prostate, breast and colorectal), insulin-dependent diabetes mellitus and schizophrenia. I hypothesise that low pre- and perinatal vitamin D levels imprint on the functional characteristics of various tissues throughout the body, leaving the affected individual at increased risk of developing a range of adult-onset disorders. The hypothesis draws from recent advances in our understanding of the early origin of adult disease and proposes a 'critical window' during which vitamin D levels may have a persisting impact on adult health outcomes. Methods to test the hypothesis are outlined. If correct, the hypothesis has important implications for public health. Careful attention to maternal vitamin D status could translate into diverse improvements in health outcomes for the following generation.

Characteristics of children with florid vitamin D deficient rickets in the Auckland region in 1998

AIM

To describe the characteristics of children with vitamin D deficiency rickets and identify common features and predisposing factors.

METHODS

A review of the clinical notes of all children less than five years of age with radiological evidence of rickets and serum 25-hydroxyvitamin D levels of less than 10 micrograms/L. Patients were identified by searching all low vitamin D levels performed at the Endocrinology laboratory at Auckland Hospital and children presenting to the Starship Childrens' Hospital with rickets in 1998.

RESULTS

In 1998, there were eighteen children (ten males and eight females) with vitamin D deficient rickets. The age range was 3 to 36 months with a median of 12 months. There were twelve children of Indian ethnic origin, one Maori, one Tongan, one Western Samoan, one Ethiopian, one Moroccan and one Indonesian. All children had an elevated alkaline phosphatase level and most had very low serum 25-hydroxyvitamin D levels (< or = 5 micrograms/L), and over half were hypocalcaemic. The common presenting features were delayed walking and bowed legs, swollen wrists or ankles, hypocalcaemic seizure, incidental radiological abnormalities and failure to thrive.

CONCLUSIONS

There are a significant number of children in Auckland presenting with florid clinical rickets. The majority with vitamin D deficient rickets in this survey were of Indian ethnic origin. Strategies are needed to detect children at risk of vitamin D deficiency and supplement them with vitamin D.

Prevalence and significance of low 25-hydroxyvitamin D concentrations in healthy subjects in Delhi

BACKGROUND

Despite abundant sunlight, rickets and osteomalacia are prevalent in South Asian countries. The cause of this paradox is not clear.

OBJECTIVE

The objective was to assess 25-hydroxyvitamin D [25(OH)D] status and its functional significance in apparently healthy subjects residing in Delhi, a city in the northern part of India.

DESIGN

Serum 25(OH)D, total calcium, inorganic phosphate, alkaline phosphatase, intact parathyroid hormone, and 1, 25-dihydroxyvitamin D [1,25(OH)(2)D] were measured in groups of healthy subjects who differed with respect to variables relevant to vitamin D and bone mineral metabolic status, such as direct sunlight exposure, season of measurement, skin pigmentation, dietary calcium and phytate contents, and altered physiologic states such as pregnancy and neonatal age.

RESULTS

All groups except one with maximum direct sunlight exposure had subnormal concentrations of 25(OH)D. The 25(OH)D-deficient groups tended to have an imbalance in bone mineral metabolic homeostasis when exposed to winter weather and low dietary calcium and high dietary phytate, with significantly low calcium and elevated intact parathyroid hormone concentrations, chemical osteomalacia, or both. Increased values of 1,25(OH)(2)D during pregnancy did not help correct the imbalance in bone mineral metabolic homeostasis.

CONCLUSION

Healthy subjects with low 25(OH)D concentrations are at risk of bone mineral metabolic imbalance when exposed to factors that strain bone mineral homeostasis.

Nutritional rickets in African American breast-fed infants

OBJECTIVE

To analyze the characteristics of infants and children diagnosed with nutritional rickets at two medical centers in North Carolina in the 1990s.

STUDY DESIGN

The physical and radiographic findings, calcium, phosphorus, alkaline phosphatase, and 25-hydroxyvitamin D levels of infants and children diagnosed with nutritional rickets at two medical centers were reviewed. Breast-feeding data were obtained from the North Carolina Women, Infants and Children Program (WIC).

RESULTS

Thirty patients with nutritional rickets were first seen between 1990 and June of 1999. Over half of the cases occurred in 1998 and the first half of 1999. All patients were African American children who were breast fed without receiving supplemental vitamin D. The average duration of breast-feeding was 12.5 months. The age at diagnosis was 5 to 25 months, with a median age of 15.5 months. Growth failure was common: length was <5th percentile in 65% of cases, and weight was <5th percentile in 43%.

CONCLUSION

Factors that may have contributed to the increase in referrals of children with nutritional rickets include more African American women breast-feeding, fewer infants receiving vitamin D supplements, and mothers and children exposed to less sunlight. We recommend that all dark-skinned breast-fed infants and children receive vitamin D supplementation.

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.

Risk factors for nutritional rickets among children in Kuwait

AIM

To assess the risk factors for nutritional rickets among children in Kuwait.

METHODS

One hundred and three children with rickets and 102 control children matched for age and socioethnic characteristics were recruited over a 2 year period (January 1995 to January 1997) in Al-Adan Hospital in Kuwait. Diagnosis was made on clinical, radiologic and biochemical parameters. A specially designed questionnaire was administered by one of the investigators to both mothers of patients and mothers of control subjects to assess the role of social, nutritional and other related factors in the pathogenesis of nutritional rickets. Biochemical investigations included estimation of hemoglobin, serum calcium, serum phosphorus, serum alkaline phosphatase and serum 25-hydroxy vitamin D.

RESULTS

The mean birthweights of rickets patients and control subjects were 3.20 +/- 0.46 and 3.19 +/- 0.45 kg, respectively. At the time of diagnosis, bodyweights of the patients and controls were 9.36 +/- 1.50 and 10.15 +/- 2.10 kg, respectively. Heights at the time of diagnosis were 73.58 and 77.24 cm for the patients and the controls, respectively. Mean hemoglobin, serum calcium and serum phosphate were significantly lower in the patients compared with the controls. Alkaline phosphatase was higher among the patients (P < 0.0001). The mean serum 25-hydroxy vitamin D level of the patients was 26.5 nmol/L, compared with 83.5 nmol/L in the controls. The mean age of starting semisolid feeds for the patients was 8.12 months, compared with 5.7 months in the controls. The nutritional quality of semisolid feeds was adequate among 71.6% of the controls as opposed to 13.6% of the patients.

CONCLUSION

Nutritional rickets is a multifactorial condition. However, several factors seem to make important contributions. Among these, lack of exposure to sunlight, prolonged breast feeding without supplementation and inadequate weaning practices are important. Maternal education is important as it can influence all of the above factors.

Vitamin D deficiency rickets in children: prevalence and need for community education

Nutritional rickets caused by a deficiency in vitamin D can be a crippling disease and is still prevalent today. Many feel that the vitamin D supplementation present in dairy products prevents any risk of developing vitamin D deficiency rickets. However, a combination of factors such as pigmented skin, inadequate sunlight, breastfeeding past 6 months with no supplementation, and insufficient calcium intake by the nursing mother and her baby often contribute to rickets diagnosed in children. Educating the medical community and those families at risk is critical to eradicate this preventable disease. Steps can be taken using stages of the Organizational Change Theory to involve school nurses, community health centers, and pediatricians in identifying these high-risk children. With prompt diagnosis and treatment, all symptoms can abate, with healthy bone growth resulting.

Rickets and deprivation: a Nigerian study

Under-fives in 461 households were assessed clinically to determine the prevalence of rickets in sub-urban and rural communities in the Sahel savanna. Overt rickets was found in 11 (2.4%) of households and abnormalities suggestive of rickets in 69 (14.9%). There were significant variations (p < 0.05) in the prevalence of rickets in association with ethnic grouping (higher in southerners and non-Kanuri, non-Hausa-Fulani northerners), religion (more prevalent among Christians), and mother's occupation and educational status (higher with working class mothers and mothers with at least a primary education). A significantly higher prevalence was also associated with late introduction (at more than seven months of age) of cereals to the infant's diet, more than one under-five in a household and presence of under-fives aged 13-43 months. In contrast, no significant variations in prevalence were observed in association with duration of breast feeding, use of multivitamins or cod liver oil, history of convulsions in under-fives, sex, nutritional status, or history of diarrhoea within a recall period of six months. Thus, rickets is common in under-fives in rural and sub-urban communities in the Sahel savanna and may be related more to environmental and dietary factors than to culture and religion. Further studies are required to determine the relative roles of vitamin D or calcium deficiency to facilitate the planning and execution of a community-based intervention programme in the area.