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Fibrogenesis imperfecta ossium
211
Abstracts Fromthe Bone &Tooth Society. (range 20% to over 80%) was 50%. Reported differences in trace element /eve/ in enamel are thus likely to be associated as much with differences in analytical performance as with population differences.
VITAMIN D METABOLISM IN EARLY PRETERM INFANTS E.B. Mawer, S.W. Stanbury, M.J. Robinson, * J. James* and C. Close* Dept. of Medicine, University Hospital of Manchester and *Royal Manchester Children’s Hospital Hypocalcaemia, sometimes accompanied by rickets may present problems in preterm infants; inability to metabolize vitamin D has been suggested as a possible cause. Glorieux et al. (J. Pediatrics, 99, 640, 1981) showed that above 32 weeks gestational age, babies could both 25- and 1-hydroxylate the vitamin, We have studied vitamin D metabolism in preterm infants of initial gestational age 26-32 weeks. Age-matched groups were given orally either 1000 iu or 3000 iu vitamin D, per day. Separate analysis of the D, and D, metabolites by HPLC and RIA enabled the metabolic fate of both exogenous and endogenous vitamin to be followed. All babies were able to absorb and 25hydroxylate vitamin D, irrespective of age, serum values rose rapidly, but the levels attained were independent of dose. Serum levels of 1,25-dihydroxyvitamin D, rose to 50-220 pglml, the increase being significantly related to that in the precursor molecule. In virtually all the babies the endogenous vitamin D, metabolites disappeared during the time of study. The inter-relations between serum concentrations of vitamin D metabolites and those of albumin, calcium and alkaline phosphatase were extremely complex and it seems unlikely that a single factor will emerge as causing neonatal hypocalcaemia. However, low initial calcium values always increased on treatment with vitamin D, even in babies not classed as vitamin D-deficient. We are grateful for support Crippled Child.
from Action Research for the
FIBROGENESIS IMPERFECTA OSSIUM M. Byron, C.G. Woods and R. Smith Nuffield Orthopaedic Centre, Headington,
Oxford
Fibrogenesis imperfecta ossium (FIO) is a very rare disorder in which the normal lamellar collagen of bone appears to be replaced by fine woven fibres to produce a tissue which is structurally unsound, does not mineralize and is not birefringent under polarized light. In two previously well adults (age 49 and 65) with bone pain and multiple fractures, bone biopsy confirmed this diagnosis. Radiographs showed generalized coarse trabeculation of the skeleton, and biochemically the alkaline phosphatase was increased. There was no significant improvement on treatment with 1 alpha hydroxycholecalciferol. No abnormality was found in skin collagen, but transmission and scanning electron microscopy of bone was very abnormal. Further investigations into the possible causes of this acquired disorder of bone collagen will be discussed.
Osteoporosis in pregnancy is rare. It is not known whether pregnancy is causal or coincidental, but study of such patients may help to understand the effect of physiological stress on the skeleton, In 8 patients, osteoporosis with loss of height and back pain occurred in association with pregnancy (in 7 in the first pregnancy); in 2 women who had subsequent pregnancies osteoporosis did not recur. Cancellous iliac bone taken at various times after an affected pregnancy was qualitatively normal or osteoporotic; quantitative measurements suggested cellular inactivity. In 3 patients the basal concentrations of 1,25(OH),D were lower than normal and in one with apparently progressive osteoporosis the basal calcitonin concentration did not increase during induced hypercalcaemia. These studies do not indicate whether pregnancy causes osteoporosis; they do show that vertebral collapse does not necessarily recur in subsequent pregnancies, that excessive bone resorption is probably not a feature, and that circulating levels of 1,25(OH),D may be low. The last two findings are similar to those reported in idiopathic juvenile osteoporosis.
RESPONSE OF THE SERUM PI-HYDROXYVITAMIN D LEVELS TO MINIMAL EXPOSURE TO SUNSHINE IN PATIENTS IN A LONG-STAY MENTAL HOSPITAL A.W.M. Hay, C. Jones and D.B. Morgan Dept. of Chemical Pathology, University of Leeds In young people, serum 25-hydroxyvitamin D (25-OHD) levels are reported to increase by some 30-37 nmol 1-l during the summer, whereas the active elderly show a smaller change (15-l 8 nmol I-‘), perhaps due to less exposure to sunlight. Patients who remain in hospital for long periods of time often have low circulating levels of 25(OH)D, even in summer. In long-stay hospitals it is recognized that exposure to sunlight is desirable and every effort is made to achieve it, but few patients get more than a few hours during the whole of the summer, To investigate the effect of these small amounts of sunlight, we measured the serum 25-OHD in 85 elderly female patientsfrom different wards of a mental hospital in April and at the beginning of November. They were compared with a group of 15 active elderly women who were studied in mid-April and at the end of August. Serum 25-OHD was measured by competitive protein binding. The average increase was 1.3 nmol 1-l in the patients and 14.2 nmol I- ’in the active elderly. When the patients were grouped according to their access to sunlight, those who were ward-bound and did not have access to a sunny veranda showed no significant increase (0.2 + 2.8 nmol 1 - ‘) during the summer. Patients who got out occasionally (no more than 6 exposures during the whole summer) showed a slight, although significant increase (1.3 + 2.7 nmol 1 -I p < 0.01). Those who had free access to sunshine (although this did not exceed 2-3 exposures per week) showed a small increase (3.8 f 3.9 nmol 1-l p < 0.01). Thus, the small amount of sunlight which these patientscan get, and which requiresgreat effort on the part of the staff, produces a negligible increase in their vitamin D levels. For this reason, most of the long-stay patients in our study are dependent on their diet for their supply of vitamin D.
OSTEOPOROSIS AND PREGNANCY
RAPID DIAGNOSIS OF METABOLIC BONE DISEASE USING FROZEN SECTION OF BONE
P. Wordsworth, *J.C. Stevenson, R. Smith and C.G. Woods N&field Orthopaedic Centre, Oxford, and ‘Endocrine Unit, Royal Postgraduate Medical School, London
A. Stevens, J. Palmer and D.J. Hosking Dept.% of Pathology and Medicine, University Hospital Nottingham
Abstracts Fromthe Bone &Tooth Society. (range 20% to over 80%) was 50%. Reported differences in trace element /eve/ in enamel are thus likely to be associated as much with differences in analytical performance as with population differences.
VITAMIN D METABOLISM IN EARLY PRETERM INFANTS E.B. Mawer, S.W. Stanbury, M.J. Robinson, * J. James* and C. Close* Dept. of Medicine, University Hospital of Manchester and *Royal Manchester Children’s Hospital Hypocalcaemia, sometimes accompanied by rickets may present problems in preterm infants; inability to metabolize vitamin D has been suggested as a possible cause. Glorieux et al. (J. Pediatrics, 99, 640, 1981) showed that above 32 weeks gestational age, babies could both 25- and 1-hydroxylate the vitamin, We have studied vitamin D metabolism in preterm infants of initial gestational age 26-32 weeks. Age-matched groups were given orally either 1000 iu or 3000 iu vitamin D, per day. Separate analysis of the D, and D, metabolites by HPLC and RIA enabled the metabolic fate of both exogenous and endogenous vitamin to be followed. All babies were able to absorb and 25hydroxylate vitamin D, irrespective of age, serum values rose rapidly, but the levels attained were independent of dose. Serum levels of 1,25-dihydroxyvitamin D, rose to 50-220 pglml, the increase being significantly related to that in the precursor molecule. In virtually all the babies the endogenous vitamin D, metabolites disappeared during the time of study. The inter-relations between serum concentrations of vitamin D metabolites and those of albumin, calcium and alkaline phosphatase were extremely complex and it seems unlikely that a single factor will emerge as causing neonatal hypocalcaemia. However, low initial calcium values always increased on treatment with vitamin D, even in babies not classed as vitamin D-deficient. We are grateful for support Crippled Child.
from Action Research for the
FIBROGENESIS IMPERFECTA OSSIUM M. Byron, C.G. Woods and R. Smith Nuffield Orthopaedic Centre, Headington,
Oxford
Fibrogenesis imperfecta ossium (FIO) is a very rare disorder in which the normal lamellar collagen of bone appears to be replaced by fine woven fibres to produce a tissue which is structurally unsound, does not mineralize and is not birefringent under polarized light. In two previously well adults (age 49 and 65) with bone pain and multiple fractures, bone biopsy confirmed this diagnosis. Radiographs showed generalized coarse trabeculation of the skeleton, and biochemically the alkaline phosphatase was increased. There was no significant improvement on treatment with 1 alpha hydroxycholecalciferol. No abnormality was found in skin collagen, but transmission and scanning electron microscopy of bone was very abnormal. Further investigations into the possible causes of this acquired disorder of bone collagen will be discussed.
Osteoporosis in pregnancy is rare. It is not known whether pregnancy is causal or coincidental, but study of such patients may help to understand the effect of physiological stress on the skeleton, In 8 patients, osteoporosis with loss of height and back pain occurred in association with pregnancy (in 7 in the first pregnancy); in 2 women who had subsequent pregnancies osteoporosis did not recur. Cancellous iliac bone taken at various times after an affected pregnancy was qualitatively normal or osteoporotic; quantitative measurements suggested cellular inactivity. In 3 patients the basal concentrations of 1,25(OH),D were lower than normal and in one with apparently progressive osteoporosis the basal calcitonin concentration did not increase during induced hypercalcaemia. These studies do not indicate whether pregnancy causes osteoporosis; they do show that vertebral collapse does not necessarily recur in subsequent pregnancies, that excessive bone resorption is probably not a feature, and that circulating levels of 1,25(OH),D may be low. The last two findings are similar to those reported in idiopathic juvenile osteoporosis.
RESPONSE OF THE SERUM PI-HYDROXYVITAMIN D LEVELS TO MINIMAL EXPOSURE TO SUNSHINE IN PATIENTS IN A LONG-STAY MENTAL HOSPITAL A.W.M. Hay, C. Jones and D.B. Morgan Dept. of Chemical Pathology, University of Leeds In young people, serum 25-hydroxyvitamin D (25-OHD) levels are reported to increase by some 30-37 nmol 1-l during the summer, whereas the active elderly show a smaller change (15-l 8 nmol I-‘), perhaps due to less exposure to sunlight. Patients who remain in hospital for long periods of time often have low circulating levels of 25(OH)D, even in summer. In long-stay hospitals it is recognized that exposure to sunlight is desirable and every effort is made to achieve it, but few patients get more than a few hours during the whole of the summer, To investigate the effect of these small amounts of sunlight, we measured the serum 25-OHD in 85 elderly female patientsfrom different wards of a mental hospital in April and at the beginning of November. They were compared with a group of 15 active elderly women who were studied in mid-April and at the end of August. Serum 25-OHD was measured by competitive protein binding. The average increase was 1.3 nmol 1-l in the patients and 14.2 nmol I- ’in the active elderly. When the patients were grouped according to their access to sunlight, those who were ward-bound and did not have access to a sunny veranda showed no significant increase (0.2 + 2.8 nmol 1 - ‘) during the summer. Patients who got out occasionally (no more than 6 exposures during the whole summer) showed a slight, although significant increase (1.3 + 2.7 nmol 1 -I p < 0.01). Those who had free access to sunshine (although this did not exceed 2-3 exposures per week) showed a small increase (3.8 f 3.9 nmol 1-l p < 0.01). Thus, the small amount of sunlight which these patientscan get, and which requiresgreat effort on the part of the staff, produces a negligible increase in their vitamin D levels. For this reason, most of the long-stay patients in our study are dependent on their diet for their supply of vitamin D.
OSTEOPOROSIS AND PREGNANCY
RAPID DIAGNOSIS OF METABOLIC BONE DISEASE USING FROZEN SECTION OF BONE
P. Wordsworth, *J.C. Stevenson, R. Smith and C.G. Woods N&field Orthopaedic Centre, Oxford, and ‘Endocrine Unit, Royal Postgraduate Medical School, London
A. Stevens, J. Palmer and D.J. Hosking Dept.% of Pathology and Medicine, University Hospital Nottingham