Hyperparathyroidism in a Large Cohort of Chinese Patients With Tumor-induced Osteomalacia.

CONTEXT: Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by excessive production of fibroblast growth factor 23 (FGF23) by a tumor. Hyperparathyroidism (HPT) including secondary HPT (SHPT) and tertiary HPT (THPT) in TIO patients, which is believed to be associated with phosphate supplementation, has not been well documented. OBJECTIVES: To clarify the prevalence, clinical characteristics, and risk factors for HPT in a large cohort of Chinese patients with TIO in our hospital. DESIGN, SETTING, AND PARTICIPANTS: This retrospective study enrolled 202 patients with TIO. MAIN OUTCOME MEASUREMENTS: Occurrence of HPT in patients with TIO. RESULTS: HPT was observed in 91 patients (91/202, 45.1%): 84 patients (41.6%) with SHPT and 7 patients (3.5%) with THPT. All patients with THPT underwent parathyroidectomy and only 1 patient experienced recurrence. Compared with patients without HPT, patients with SHPT had longer disease duration, higher rate of phosphate and calcitriol supplementation, lower serum calcium, lower urine calcium excretion, and higher urine phosphate excretion. Compared with patients with SHPT, patients with THPT had even longer disease duration and a higher rate of phosphate and calcitriol supplementation. PTH levels showed positive correlation with intact FGF23 and 1,25-dihydroxyvitamin D levels, but not 25-hydroxy vitamin D level in patients with TIO. Multivariate logistic regression analysis showed that long disease duration and phosphate supplementation were independently associated with occurrence of HPT in patients with TIO. Further logistic regression analysis and restricted cubic spline model revealed dose-response relationship between cumulative dose of phosphate supplementation and PTH levels. CONCLUSIONS: HPT is common in patients with TIO. To avoid the occurrence of HPT in patients with TIO, timely diagnosis and tumor resection is necessary and an excessive dose of phosphate supplementation is not suggested before surgery.

Vitamin D deficiency, supplementation and testing: have we got it right in New Zealand?

BACKGROUND: Severe prolonged vitamin D deficiency can cause rickets or osteomalacia. Both can be prevented by sunshine exposure or vitamin D supplementation. Although New Zealand guidance does not recommend vitamin D supplementation for the general population, it can be considered for individuals at risk of vitamin D deficiency. Routine measurement of 25-hydroxyvitamin D (25OHD) is also considered unnecessary. METHODS: We investigated the rates of vitamin D supplementation, rickets and osteomalacia in New Zealand, and of 25OHD results in Auckland, over the last two decades. RESULTS: Vitamin D prescriptions increased 14-fold, from 86,295/year to 1,215,507/year, between 2003 and 2019, with medication costs alone in 2019 being >$1 million. Despite these changes, the annual prevalence of hospital admissions for rickets, osteomalacia and unspecified vitamin D deficiency remained low and stable (10-20/year). 25OHD concentrations increased between 2002 and 2003 and between 2009 and 2019, and in the later time-period, 25OHD tests mainly identified individuals without vitamin D deficiency (40-50% >75nmol/L, 65-70% >50nmol/L and only 7-12.5% <25nmol/L). CONCLUSIONS: Osteomalacia and rickets persist at low rates despite widespread, increasingly costly vitamin D supplementation and testing, which largely identifies individuals without vitamin D deficiency. These results suggest that vitamin D guidance and practice in New Zealand should change.

Prevalence of biochemical osteomalacia in adults undergoing vitamin D testing.

OBJECTIVE: Prolonged severe vitamin D deficiency can cause osteomalacia, but the 25-hydroxyvitamin D (25OHD) concentration below which this occurs is unknown. We investigated the prevalence of biochemical osteomalacia in adults with a measurement of 25OHD. DESIGN, MEASUREMENT, AND PATIENTS: 25OHD results between 1/1/2009 and 15/6/2020 were obtained from the regional laboratory database, together with measurements of serum calcium, parathyroid hormone (PTH) and alkaline phosphatase (ALP) within 6 months of the index 25OHD. We defined biochemical osteomalacia as all 3 of: albumin-adjusted serum calcium (aCa)<2.0 mmol/L, PTH>7.3 pmol/L and ALP>150 IU/L. Possible osteomalacia was 2/3 criteria with the other test not done. 25OHD measurements associated with significant renal impairment, elevated hepatic transaminases or hypercalcaemia were excluded. RESULTS: 110,046 25OHD measurements were identified over the 11.5 years period. After removal of ineligible measurements, 42,171 25OHD measurements from 32,386 individuals with at least 2 of aCa, PTH and ALP were included in analyses. Median 25OHD was 63 nmol/L; 8% were <25 nmol/L, and 33% were <50 nmol/L. Five index 25OHD measurements met the definition of biochemical osteomalacia, and another 11 were possible osteomalacia. After reviewing available clinical records for these 16 episodes, we classified 9 cases as osteomalacia and 7 as other diagnoses. Thus, the prevalence of biochemical osteomalacia was 0.02% (9/42,171) for 25OHD measurements and 0.23% (8/3432) for 25OHD<25 nmol/L. All cases of osteomalacia with 25OHD measurements prior to supplementation had 25OHD≤18 nmol/L. CONCLUSION: The prevalence of biochemical osteomalacia is very low, even in individuals with 25OHD<25 nmol/L.

Vitamin D and Cardiovascular Disease: An Updated Narrative Review.

During the last two decades, the potential impact of vitamin D on the risk of cardiovascular disease (CVD) has been rigorously studied. Data regarding the effect of vitamin D on CVD risk are puzzling: observational data indicate an inverse nonlinear association between vitamin D status and CVD events, with the highest CVD risk at severe vitamin D deficiency; however, preclinical data and randomized controlled trials (RCTs) show several beneficial effects of vitamin D on the surrogate parameters of vascular and cardiac function. By contrast, Mendelian randomization studies and large RCTs in the general population and in patients with chronic kidney disease, a high-risk group for CVD events, largely report no significant beneficial effect of vitamin D treatment on CVD events. In patients with rickets and osteomalacia, cardiovascular complications are infrequently reported, except for an increased risk of heart failure. In conclusion, there is no strong evidence for beneficial vitamin D effects on CVD risk, either in the general population or in high-risk groups. Whether some subgroups such as individuals with severe vitamin D deficiency or a combination of low vitamin D status with specific gene variants and/or certain nutrition/lifestyle factors would benefit from vitamin D (metabolite) administration, remains to be studied.

Spot the silent sufferers: A call for clinical diagnostic criteria for solar and nutritional osteomalacia.

Osteomalacia and rickets result from defective mineralization when the body is deprived of calcium. Globally, the main cause of osteomalacia is a lack of mineral supply for bone modeling and remodeling due to solar vitamin D and/or dietary calcium deficiency. Osteomalacia occurs when existing bone is replaced by unmineralized bone matrix (osteoid) during remodeling in children and adults, or when newly formed bone is not mineralized in time during modeling in children. Rickets occurs when hypomineralization affects the epiphyseal growth plate chondrocytes and adjacent bone metaphysis in growing children. Hence, osteomalacia co-exists with rickets in growing children. Several reports in the last decade highlight the resurgence of so-called "nutritional" rickets in the dark-skinned population living in high-income countries. However, very few studies have ever explored the hidden iceberg of nutritional osteomalacia in the population. Rickets presents with hypocalcaemic (seizures, tetany, cardiomyopathy), or hypophosphataemic complications (leg bowing, knock knees, rachitic rosary, muscle weakness) and is diagnosed on radiographs (cupping and fraying of metaphyses). In contrast, osteomalacia lacks distinctive, non-invasive diagnostic laboratory or imaging criteria and the clinical presentation is non-specific (general fatigue, malaise, muscle weakness and pain). Hence, osteomalacia remains largely undiagnosed, as a hidden disease in millions of dark-skinned people who are at greatest risk. Radiographs may demonstrate Looser's zone fractures in those most severely affected, however to date, osteomalacia remains a histological diagnosis requiring a bone biopsy. Biochemical features of high serum alkaline phosphatase (ALP), high parathyroid hormone (PTH) with or without low 25 hydroxyvitamin D (25OHD) concentrations are common to both rickets and osteomalacia. Here, we propose non-invasive diagnostic criteria for osteomalacia. We recommend a diagnosis of osteomalacia in the presence of high ALP, high PTH, low dietary calcium intake (<300 mg/day) and/or low serum 25OHD (<30 nmol/L). Presence of clinical symptoms (as above) or Looser's zone fractures should be used to reaffirm the diagnosis. We call for further studies to explore the true prevalence of nutritional osteomalacia in various populations, specifically the Black and Asian ethnic groups, in order to identify the hidden disease burden and inform public health policies for vitamin D/calcium supplementation and food fortification.

Prevention of rickets and osteomalacia in the UK: political action overdue.

The consequences of vitamin D and dietary calcium deficiency have become a huge public health concern in the UK. The burden of disease from these deficiencies includes rickets, and hypocalcaemic seizures, dilated cardiomyopathy and mostly occult myopathy and osteomalacia. The increasing burden of the disease is intrinsically linked to ethnicity and the population demographic changes in the UK. Three facts have led to the resurfacing of the English disease: (1) the UK has no ultraviolet sunlight for at least 6 months of the year, (2) dark skin produces far less vitamin D than white skin per unit ultraviolet light exposure, and (3) non-European Union immigration over the last century. To date, the UK government demonstrates incomplete understanding of these three facts, and its failure to adjust its prevention programmes to changing demographics is endangering the health and life of UK residents with dark skin, of whom infants are the most vulnerable. Establishing accountability through the implementation of monitored antenatal and infantile supplementation programmes and mandatory food fortification is overdue.

Osteomalacia tumoral: un síndrome paraneoplásico emergente / Tumour-induced osteomalacia: An emergent paraneoplastic syndrome

Los síndromes paraneoplásicos endocrinos constituyen manifestaciones a distancia de algunas neoplasias. Una forma infrecuente, pero cada vez más descrita, es la osteomalacia tumoral (OT), un trastorno hipofosfatémico secundario a la pérdida renal de fosfatos inducida por la secreción tumoral del factor de crecimiento fibroblástico 23 (FGF-23). Sus principales manifestaciones bioquímicas son la hipofosfatemia, la reabsorción tubular de fosfatos inadecuadamente normal o baja, los niveles bajos de calcitriol, la fosfatasa alcalina elevada y el FGF-23 sérico elevado o normal. Los tumores asociados a la OT suelen ser pequeños, benignos, de lento crecimiento, de difícil localización y con predominio en las partes blandas de los miembros. La histología más frecuente son los tumores mesenquimales fosfatúricos tipo tejido conectivo mixto. Se han propuesto varias técnicas de imagen para su identificación con resultados variables. El tratamiento de elección es la resección quirúrgica completa de la lesión. Otras alternativas terapéuticas son las sales de fósforo, el calcitriol, la octreótida, el cinacalcet y los anticuerpos monoclonales (AU)

Endocrine paraneoplastic syndromes are distant manifestations of some tumours. An uncommon but increasingly reported form is tumour-induced osteomalacia, a hypophosphatemic disorder associated to fibroblast growth factor 23 (FGF-23) secretion by tumours. The main biochemical manifestations of this disorder include hypophosphatemia, inappropriately low or normal tubular reabsorption of phosphate, low serum calcitriol levels, increased serum alkaline phosphatase levels, and elevated or normal serum FGF-23 levels. These tumours, usually small, benign, slow growing and difficult to discover, are mainly localized in soft tissues of the limbs. Histologically, phosphaturic mesenchymal tumours of the mixed connective tissue type are most common. Various imaging techniques have been suggested with variable results. Treatment of choice is total surgical resection of the tumour. Medical treatment includes oral phosphorus and calcitriol supplements, octreotide, cinacalcet, and monoclonal antibodies (AU)

Vitamin D Status in South Asian Populations - Risks and Opportunities.

Human body acquires a significant amount of vitamin D by cutaneous synthesis under the action of sunlight and less is supplied through nutritional sources. Diversified sociocultural and economic determinants have been identified that limit the dietary intake of vitamin D and enough distribution of sunlight to maintain optimal levels of 25-hydroxyvitamin D (25(OH)D). Consequently, the world has witnessed a high prevalence of hypovitaminosis D in resource-limited South Asian countries. The purpose of this review is to provide a South Asian perspective of vitamin D status, critically examining India, Pakistan, Bangladesh, and Sri Lanka, and to shed light on potential determinants (latitude and season, sunshine exposure habits, age, gender, and genetic factors) leading to hypovitaminosis D among a variety of population groups. Literature search was carried out using bibliographic databases "PubMed," "Google Scholar," and "ScienceDirect.com." Serum 25(OH)D level, 20-50 nmol/L, was mainly taken as vitamin D deficiency, and determinants of low serum 25(OH)D concentration of the population under study were also considered. The review concludes that vitamin D deficiency is highly prevalent among South Asian populations and global efforts are needed to overcome hypovitaminosis in the region. In addition, dietary diversification, supplementation and fortification of foods with vitamin D, adequate exposure to sunlight, and consumption of animal foods were suggested as viable approaches to maintain 25(OH)D levels for optimal health.

Lower bone mineral density in Somali women living in Sweden compared with African-Americans.

UNLABELLED: Vitamin D deficiency can lead to osteomalacia. Bone mineral density was lower in Somali women, living in Sweden, in relation to both the American and the African-American reference populations. The majority, 73 %, had vitamin D deficiency, and supplementation should be considered to prevent from osteomalacia, osteoporosis and future fractures. PURPOSE: Low vitamin D can lead to osteomalacia. The hypothesis was that bone mineral density (BMD) in Somali women living in Sweden was lower in comparison with different ethnic reference populations. METHODS: Women from Somalia, n = 67, median age 35.8 years (range 18 to 56), latitude 0-10° North living in Gothenburg, Sweden, latitude 57° North, >2 years were studied. All wore traditional Islamic clothing and had skin photo type V. BMD was recorded as the Z-score and compared with white American and African-American women, respectively, using standard data from the dual energy X-ray absorptiometry (DXA) manufacturer (Lunar Prodigy enCORETM, GE Healthcare, LU44663). A fasting blood test was drawn for analysis of serum 25(OH)D. RESULTS: The median Z-score compared with the American white population was -0.9 SD of the lumbar spine (p < 0.00001), 0.1 SD of the left hip and 0.0 SD of the right hip (ns). The median Z-score compared with the African-American population was -1.6 SD of the lumbar spine (p < 0.00001), -0.9 SD of the left hip and -0.9 SD of the right hip (p < 0.001). The majority, 73 %, had vitamin D deficiency, serum 25(OH)D <25 nmol/l (<10 ng/ml). BMD did not correlate to vitamin D levels or to the number of years in Sweden. One wrist fracture was reported. CONCLUSIONS: BMD was lower in these fairly young immigrant women from Somalia, living in Sweden, in relation to both the American and the African-American reference populations. Vitamin D supplementation should be considered to prevent from osteomalacia, osteoporosis and future fractures.

Hyperparathyroidism and complications associated with vitamin D deficiency in HIV-infected adults in New York City, New York.

Although recent studies report a high prevalence of vitamin D deficiency in HIV-infected adults similar to that in the general population, metabolic complications of vitamin D deficiency may be worsened with HIV infection and remain insufficiently characterized. We conducted a retrospective cross-sectional cohort study to determine prevalence and correlates of vitamin D deficiency and hyperparathyroidism among HIV-infected patients attending an urban clinic. Vitamin D deficiency was defined as 25(OH)-vitamin D <20 ng/ml and insufficiency as 20 to <30 ng/ml, and hyperparathyroidism as parathyroid-hormone >65 pg/ml. We used the X(2) test to compare proportions and logistic regression to assess for associations. Among 463 HIV-infected patients, the prevalence of vitamin D deficiency was 59%. The prevalence of hyperparathyroidism was 30% among patients with vitamin D deficiency, 23% among those with insufficiency, and 12% among those with sufficient vitamin D levels. Vitamin D deficiency was associated with increased odds of hyperparathyroidism. Severe vitamin D deficiency was associated with elevated alkaline phosphatase, a marker for increased bone turnover. Although efavirenz use was associated with vitamin D deficiency, and protease inhibitor use with decreased odds of vitamin D deficiency, there was no statistical difference in rates of hyperparathyroidism stratified by combination antiretroviral therapy (cART) use. Given the increased risk of osteopenia with HIV infection and cART use, vitamin D supplementation for all HIV-infected patients on cART should be prescribed in accordance with the 2011 Endocrine Society guidelines. In HIV-infected patients with severe vitamin D deficiency or hyperparathyroidism, screening for osteomalacia and osteopenia may be warranted.

Bone disorders in chronic liver diseases.

Bone disease is a major complication of chronic liver disease. Osteomalacia is quite uncommon despite low vitamin D levels in the majority of patients with cirrhosis. In contrast, osteoporosis is quite common, occurring in up to 50% of patients. Osteoporosis can result in spontaneous or low-impact fractures in patients with chronic liver diseases, adversely affecting morbidity, quality of life, and survival. The general biology of osteoporosis, including its pathogenesis, diagnostic tools, and rationale for treatment, have been determined largely empirically from studies of postmenopausal women with osteoporosis. Treatment regimens with modification of risk factors, use of vitamin D, and supplementation with calcium and bisphosphonates have been shown to be effective in select groups of patients with chronic liver diseases.

A survey of vitamin D level in people with learning disability in long-stay hospital wards in Hong Kong.

Serum vitamin D level was measured in 122 patients with learning disabilities in long-term care wards. Such people are at risk of developing vitamin D deficiency. Low vitamin D is often attributed to lack of sunshine, poor dietary intake and the deleterious effect of anticonvulsant therapy. The results of this study confirmed that a low level of vitamin D (14.38 +/- 7.9 nmol/l) prevails, regardless of anticonvulsant usage. Sunshine exposure was virtually non-existent for most patients. Research has shown that when sunlight exposure is limited, osteomalacia in the British Asian community is determined by dietary factors. Our subjects had three types of diet: standard, soft and tube feeding. For both males and females, the tube feeding group had a significantly higher mean level of vitamin D than the other groups. Regular sunshine exposure is recommended for people requiring long-term infirmary care; alternatively, dietary supplement of vitamin D should be considered.

High prevalence of vitamin D deficiency among pregnant women and their newborns in northern India.

BACKGROUND: Vitamin D deficiency is prevalent in India, a finding that is unexpected in a tropical country with abundant sunshine. Vitamin D deficiency during pregnancy has important implications for the newborn and infant. There are few data from India about the prevalence of hypovitaminosis D in pregnancy and in the newborn. OBJECTIVE: Our aim was to determine the prevalence of osteomalacia and hypovitaminosis D in pregnancy and in cord blood and to correlate maternal 25-hydroxyvitamin D [25(OH)D] status with sun exposure, daily calcium intake (dietary plus supplemental), and intact parathyroid hormone (PTH) concentrations. DESIGN: Serum calcium, inorganic phosphorus, 25(OH)D, heat-labile alkaline phosphatase, and PTH were studied in 207 urban and rural pregnant subjects at term. Alkaline phosphatase and 25(OH)D were measured in the cord blood of 117 newborns. RESULTS: Mean maternal serum 25(OH)D was 14 +/- 9.3 ng/mL, and cord blood 25(OH)D was 8.4 +/- 5.7 ng/mL. PTH rose above the normal range when 25(OH)D was <22.5 ng/mL. Eighty-four percent of women (84.3% of urban and 83.6% of rural women) had 25(OH)D values below that cutoff. Fourteen percent of the subjects had elevated alkaline phosphatase (17% of urban and 7% of rural subjects). Calcium intake was uniformly low, although higher in urban (842 +/- 459 mg/d) than in rural (549 +/- 404 mg/d) subjects (P < 0.001). Maternal serum 25(OH)D correlated positively with cord blood 25(OH)D (r = 0.79, P < 0.001) and negatively with PTH (r = -0.35, P < 0.001). CONCLUSION: We observed a high prevalence of physiologically significant hypovitaminosis D among pregnant women and their newborns, the magnitude of which warrants public health intervention.

Studies on rickets and osteomalacia in Bactrian camels (Camelus bactrianus).

Epidemiological studies have indicated incidences of 32.9% and 27.8% for rickets and osteomalacia, respectively, in Bactrian camels (Camelus bactrianus), but there is an increased incidence under drought conditions, sometimes reaching 75%. We have found that concentrations of phosphorus and copper in forage and soil samples in a drought affected area were significantly lower than in a control area or normal reference values (P < 0.01) ; the mean Ca:P ratio in the forages was 50:1. The phosphorus content of blood and hair from affected camels was significantly less than that in controls (P < 0.01) and concentrations of copper in the liver and kidney were significantly lower in affected camels than control animals (P < 0.01); the concentrations of triiodothyronine (T(3)), thyroxine (T(4)) and parathyroid hormone (PTH) in the serum from affected animals were significantly higher than those from healthy controls (P < 0.01); serum inorganic phosphorus and ceruloplasmin levels were lower than those in the controls (P < 0.01 or P < 0.05); the concentrations of serum alpha-globulin and beta-globulin were significantly higher in the affected camels than in the healthy controls (P < 0.01). The pathological changes seen in camels affected with rickets included porous, brittle, light, osteoporotic bones that were susceptible to fractures and had less resistance to cutting and sawing. Wrist joints were enlarged with an apparent bowing of the long bones in forelimb and with typical broadening of the epiphyses. In adult female camels, many enlarged scars were often seen in ribs indicating earlier fractures. The disease could be cured with supplementary bone meal, phosphate or mineral mixtures and in field investigations clinical signs disappeared within 15 days. Over the same period, the concentrations of phosphorus and alkaline phosphatase in blood returned to normal. The disease may be effectively prevented by use of mineral blocks (block salt licks) or dosing orally with copper, selenium and cobalt soluble glass boluses. We conclude that rickets and osteomalacia are mainly caused by phosphorus and copper deficiencies in the pasture.

Osteomalacia in Hazara District, Pakistan.

Osteomalacia is most commonly seen in the remoter northern regions (Kohistan District) of Hazara District, Pakistan. Low serum calcium is common, as is tetany, but not universal. A 2% prevalence was found retrospectively in all obstetric patients from 1978--1985. Overall, there was a 12% caesarean section rate (61/annum), of which 37% (22) exhibited cranio-pelvic disproportion, nearly half of which (n=83, 46%) were thought clinically to be due to osteomalacia. Osteomalacia was found prospectively in 3.6% of all female outpatients (3600/100,000). Purdah did not appear to influence the incidence of osteomalacia, although sunlight exposure varied significantly due to place of abode (0.05 > P> 0.025); those living in the deeper, darker valleys suffered more from osteomalacia and its side effects, such as cranio-pelvic disproportion and the resulting need for caesarean sections. Diet is an important factor, showing little variety in the affected region; it lacks animal protein and is low in calories.The estimated intake of vitamin D is approximately 1 microg per day, seriously short of the daily requirement of 2.5 microg. The other main factor is higher parity in the women with osteomalacia (15/18 affected women had more than three pregnancies compared with 9/18 controls; odds ratio 13, 0.05 > P> 0.025). These all indicate that in a marginal situation added metabolic stress can precipitate the condition. While supplementation of the diet is essential in such communities it will be difficult to initiate and maintain. We therefore also recommend that strategies for prevention be focused on the men to encourage them to help improve the diet and lifestyle of their womenfolk.

Low vitamin D status, high bone turnover, and bone fractures in centenarians.

The oldest olds, including centenarians, are increasing worldwide and, in the near future, will represent a consistent part of the population. We have studied bone status and metabolism in 104 subjects over 98 yr of age to evaluate possible interventions able to avoid fragility fractures and disability. Ninety females and 14 males not affected by any acute disease were considered. After a complete clinical assessment, blood was drawn for evaluating bone turnover markers, and performance tests together with skeletal ultrasonography (either at the phalanges or at the heel) were performed. We found that 38 subjects had sustained a total of 55 fractures throughout their lives, and 75% of these were fragility fractures. Twenty-eight fractures occurred at the proximal femur, with 14 after the age of 94 yr. Serum 25-hydroxyvitamin D was undetectable in 99 of 104 centenarians. PTH and serum C-terminal fragment of collagen type I were elevated in 64 and 90% of centenarians, respectively, with a trend toward hypocalcemia. Bone alkaline phosphatase levels were close to the upper limit. Serum IL-6 was elevated in 81% of centenarians and was positively correlated with PTH and negatively correlated with serum calcium. Serum creatinine was not correlated with PTH. Bone ultrasonography showed that most centenarians had low values, and ultrasonographic parameters were correlated with resorption markers. We conclude that the extreme decades of life are characterized by a pathophysiological sequence of events linking vitamin D deficiency, low serum calcium, and secondary hyperparathyroidism with an increase in bone resorption and severe osteopenia. These data offer a rationale for the possible prevention of elevated bone turnover, bone loss, and consequently the reduction of osteoporotic fractures and fracture-induced disability in the oldest olds through the supplementation with calcium and vitamin D.

Hepatic osteodystrophy in chronic cholestasis: evidence for a multifactorial etiology.

Children with cholestatic liver disease have been thought to develop hepatic osteodystrophy resulting from vitamin D and calcium malabsorption, resulting in secondary hyperparathyroidism and osteomalacia or rickets. However, treatment with vitamin D has not always proven successful in improving the bone disturbance. The aim of our study was to determine the role of vitamin D deficiency in the pathogenesis of hepatic osteodystrophy. We studied five patients, three female and two male, ages 0.9-19 yr, with biopsy-proven chronic cholestatic liver disease and previously low serum levels of vitamin D despite oral intake of vitamin D preparations. Patients were admitted to the Clinical Research Center for 8 days for sunlight deprivation and ultraviolet light substitution and for determinations of serum 25-hyroxyvitamin D(25(OH)) D2 and -D3, osteocalcin, and type I collagen telopeptide (ICTP), the last two being markers of bone formation and resorption, respectively. Samples were taken on admission, at discharge, and 1 month later. Results demonstrated low serum levels of osteocalcin and normal circulating levels of ICTP. Admission serum 25(OH)D2 levels were uniformly low or undetectable and remained so. Admission levels of circulating 25(OH)D3 were normal or low and did not rise during ultraviolet light therapy or subsequent resumption of oral vitamin D therapy and remained low 1 month later. These results indicate that in the face of low-normal to low total 25(OH)D levels, the low osteocalcin and normal ICTP levels suggest that decreased bone formation and not increased bone resorption is the main determinant of bone loss in a subset of children with chronic cholestatic liver disease.

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.

Estudio de la osteomalacia y raquitismo en diferentes períodos históricos en colombia / Study of osteomalacia in diferent historical periods in Colombia

Dividimos el trabajo en tres etapas. En la primera buscamos la recopilación de la información sobre raquitismo y osteomalacia desde finales del siglo XIX hasta 1960. En la segunda etapa revisamos los archivos estadísticos de la Unidad de Reumatología del Hospital San Juan de Dios desde su creación en 1967, y los pacientes que se consultaban desde esa época. La tercera etapa fue dividida en dos sub-etapas, la primera sub-etapa se refiere al estudio prospectivo del foco de raquitismo en el municipio de Suárez en 1991, y la segunda sub-etapa trata sobre los casos prospectivos desde 1984 hasta Marzo del 2000 en la Clínica de Fracturas de Barranquilla, el Hospital San Juan de Dios de Bogotá, y los casos remitidos a uno de los investigadores. En la primera etapa sólo encontramos la tesis del Dr. Francisco Sorzano, publicada en 1899. Estudió 6 casos de raquitismo secundario, hipovitaminosis D y de desnutrición proteico calórica. Se utilizan por primera vez el aceite de hígado de bacalao y sales de calcio y fosfatos. A partir de 1960 se estudian 7 familias y se describen por primera vez en Colombia el raquitismo hipofosfatémico ligado al cromosoma X, es el caso de cuatro familias con raquitismo hipofosfatémico y dos familias con raquitismo hipocalcémico. En 1991 describimos el clúster más grande del mundo, aproximadamente 400 pacientes, pero sólo informamos sobre 64 pacientes. Demostramos qué es un raquitismo dependiente de vitamina D tipo IIB; es estudiado con más detenimiento el receptor de la vitamina D, el cual fue encontrado normal, aunque el defecto se encuentra a nivel posttranslacional. De forma prospectiva, a partir de 1984 estudiamos 19 pacientes con raquitismo y osteomalacia, asociadas a diferentes etiologías e introducimos los estudios de desintometría ósea, los niveles polares de vitamina D, hormona paratiroidea (PTH), y las iso-enzimas de la fosfatasa alcalina (AU)

Osteomalacia y raquitismo. análisis y estudio en diferentes períodos históricos en colombia / Osteomalacia and riketts. Analysis and study of different historic periods in Colombia

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