Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increased urinary excretion of phosphorylethanolamine (P.E.A.) is one of the salient features of hypophosphatasia. This inherited disorder is generally transmitted as an autosomial recessive trait and is characterized by abnormal mineralization of bone, premature loss of deciduous teeth and reduced tissue and serum alkaline phosphatases (A.P.) levels. The authors report a series of patients presenting with pains of skeletal origin attributed to an osteomalacia syndrome on the ground of a bone biopsy. These patients had no history of rickets during childhood but complained of early severe caries of the permanent dentition before the age of twenty. They had neither malabsorption nor renal tubular abnormalities. Their serum 25 OH vitamin D was normal and their serum A.P. levels were within the normal range with a normal isoenzyme distribution. All these patients had increased excretions of urinary P.E.A. and the latter correlate significantly with the degree of osteomalacia. Control patients with a malabsorption syndrome, showing osteomalacia and serum A.P. of the same degree of magnitude as the patients of the first group, have a normal P.E.A. excretion and no correlation appears between the degree of osteomalacia and the P.E.A. excretion. The cases with increased P.E.A. excretion may correspond to adult pseudohypophosphatasia. The signification of increased P.E.A. excretion is discussed.
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PMID:[Osteomalacia in hyperphosphoethanolaminuria without hypophosphatasia (author's transl)]. 47 10

Hepatic osteodystrophy consists of three types: osteomalacia, osteoporosis, and periosteal reaction with new bone formation. Secondary hyperparathyroidism is very rare, if it occurs at all. The cause of osteomalacia appears to be vitamin D deficiency due to a lack of vitamin D substrate. In the presence of adequate substrates, 25-OHD and dihydroxy vitamin D metabolites are formed. The vitamin D deficiency results in osteomalacia and malabsorption of calcium and phosphorus. The osteomalacia can be treated successfully with vitamin D supplements. In some patients calcium, phosphorus, and magnesium supplements may be required. The aetiology and treatment of the osteoporosis and the periosteal reactions remain obscure.
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PMID:Hepatic osteodystrophy. 70 74

In this 54 year old woman with celiac disease, osteomalacia developed while she was on a gluten-free diet which had caused regression of her steatorrhea. She was not responsive to large doses of parenterally administered dihydrotachysterol and calcium, but she was responsive to the oral administration of 25-hydroxyvitamin D3 (25-OHD3). The data suggest that 25-OHD3 is the treatment of choice for patients with vitamin D deficiency due to intestinal malabsorption.
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PMID:Osteomalacia and celiac disease: response to 25-hydroxyvitamin D. 74 23

Obviously, the relentless decrease in bone mass that accompanies aging will continue the long sought "elixir of youth" is discovered. Individuals, because of race, sex, environmental, dietary, genetic or activity differences, will be more or less predisposed to symptomatic osteoporosis with increasing age. The careful and knowledgeable physician should, however, make every attempt to rule out potentially remediable, subtle forms of demineralizing disorders, such as apathetic or T3-thyrotoxicosis, hyperparathyroidism, malabsorption and osteomalacia or multiple myeloma. Not only do these diseases result in an accelerated loss of bone mass and an increased incidence of skeletal fractures but they mimic postmenopausal or senile osteoporosis radiologically. Once the metabolic or malignant disorders of bone metabolism have been effectively considered and ruled out, the senescent or postmenopausal osteoporotic patient should be treated judiciously with short-term estrogen therapy, a diet sufficient in vitamin D and calcium content and continued attempts to insure adequate skeletal mobilization. The addition of sodium fluoride and/or calcitonin to this regimen should not be attempted without extreme caution until the potentially harmful systemic effects of prolonged therapeutic trials have been appropriately assessed.
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PMID:Senile and postmenopausal osteoporosis. 76 91

Oncogenic osteomalacia is a syndrome in which unexplained osteomalacia remits after resection of a coexisting mesenchymal tumor. We have investigated the mechanism by which a giant cell tumor of bone caused biopsy-proved osteomalacia in a 42-yr-old woman. The biochemical abnormalities were: hypophosphatemia; decreased renal tubular maximum for the reabsorption of phosphate per liter of glomerular filtrate; negative calcium and phosphorus balance; hyperaminoaciduria; and subnormal calcemic response to exogenously administered parathyroid hormone. Malabsorption, hypophosphatasia, fluorosis, and acidosis were excluded as causes of the osteomalacia. Serum 25-hydroxycholecalciferol was normal (27+/-1 ng/ml). However, the serum concentration of 1alpha,25-dihydroxycholecalciferol was low (1.6+/-0.1 ng/100 ml). Oral administration of physiological amounts of 1alpha,25-dihydroxycholecalciferol resulted in resolution of the biochemical abnormalities of the syndrome and healing of the bone pathology. We suggest that tumor-induced inhibition of 1alpha,25-dihydroxycholecalciferol synthesis caused the osteomalacia. The causal role of the tumor was proved by demonstrating that resection was accompanied by roentgenographic evidence of bone healing and maintenance of normal serum phosphorus; renal tubular maximum for the reabsorption of phosphate; calcium and phosphorus balance; aminoaciduria; and calcemic response to exogenous parathyroid hormone.
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PMID:Osteomalacia due to 1alpha,25-dihydroxycholecalciferol deficiency. Association with a giant cell tumor of bone. 90 49

Experimental evidence is presented which suggests that age-induced changes in the collagenous matrix, the main constituent of the organic portion of bones, are at least partially responsible for age-induced physiological osteoporotic changes in the skeleton. In particular, there seems to be a labile fraction of recently synthesized collagen in bones, which loses its metabolic activity rapidly with advancing age. Experimental and clinical hormonal disorders and disturbances in calcium metabolism also cause changes in skeletal metabolism; these changes seem to be largely mediated through changes in the collagenous matrix. In experimental hyperthyroidism and hyperparathyroidism, the rate of degradation of the collagenous matrix appears to act as a moderator or "final messenger" in hormone-induced bone resorption. In conditions with altered calcium metabolism, such as malabsorption associated with hypocalcemia, altered bone metabolism may be due to osteomalacia or hypocalcemia-induced hyperparathyroidism. An increase in the rate of bone destruction in relation to the rate of bone formation is probably also the cause of postmenopausal osteoporosis. At present there is no optimal form of hormonal treatment for age-induced or post menopausal osteoporosis. Estrogen replacement therapy may be the best available treatment for postmenopausal osteoporosis, but slowing down the already low rate of bone catabolism in elderly subjects by estrogen or other therapeutic means requires long periods of treatment before pronounced increases in the total mass of bones take place and prophylactic administration of estrogen may produce better results.
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PMID:Relation to osteoporosis of age- and hormone-induced changes in the metabolism of collagen and bone. 97 17

The pathogenesis, clinical course and treatment of senile-postmenopausal osteoporosis are reviewed. It is likely that several factors, including genetic and racial determinants as well as nutritional calcium and/or vitamin D deficiency in the elderly play a pathogenic role. Available data are consistent with the possibility that the primary alteration of bone metabolism in senile-postmenopausal osteoporosis may be a decrease in de-novo bone formation below the level necessary to compensate for age-related bone loss. The second part of the study deals with the osteomalacia syndrome. The most common known causes of osteomalacia are vitamin D deficiency, especially secondary to malabsorption, and a defective vitamin D metabolism associated with chronic renal insufficiency or prolonged anticonvulsant therapy. The hypophosphatemic forms of osteomalacia may be induced by renal tubular dysfunction or by phosphate deficiency of other origin; in these disorders a pathogenic role of altered vitamin D metabolism has not yet been established.
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PMID:[Osteoporosis and osteomalacia]. 112 74

The authors report five cases of an association between osteomalacia and chronic calcifying pancreatitis. The pancreatic involvement, which was pain-free in four patients, resulted in all cases in enzyme insufficiency with steatorrhoea. The deficiency-type osteopathy was highly vitamin sensitive. Aetiological study of these cases of osteomalacia revealed the constant presence of factors aggravating the vitamin deficiency, playing a role by increasing deficient intake or malabsorption, or by increasing Vitamin D requirements. It thus appears that hypovitaminosis D alone, of particular severity, was sufficient to result in the appearance of clinically evident osteomalacia. Such a vitamin deficiency, necessary when the intestinal mucosa is intact, is only rarely encountered, which accounts for the extreme rarity of osteomalacia in association with chronic pancreatic disorders.
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PMID:[Osteomalcaia and chronic pancreatis. 5 cases]. 121 65

A 59-year-old male patient presented with invalidating osteomalacia of 2.5 years' duration. The osteomalacia was caused by severe malabsorption due to gluten-sensitive enteropathy (GSE). There were no other signs or symptoms of GSE in this patient. Clinical presentation with monosymptomatic osteomalacia is very unusual. It seems that patients with GSE who undergo little exposure to the sun are at particular risk of developing overt osteomalacia. Unrecognized GSE should always be considered in the differential diagnosis of osteomalacia.
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PMID:A patient with osteomalacia as single presenting symptom of gluten-sensitive enteropathy. 783 24

Serum 25-hydroxyvitamin D declines in elderly subjects. This decrease reflects, in part, a lower vitamin D intake. But changes in serum 25-hydroxyvitamin D are more marked in the northern latitudes of the world because less vitamin D synthesis occurs n the skin as a result of a reduced amount of ultraviolet light. Consequently, vitamin D deficiency leading to osteomalacia is more common in thr northern latitudes, particularly among the elderly. The Recommended Daily Allowance of 200 IU of vitamin D in the elderly may be insufficient, since higher doses of 800 IU/day have been shown to reduce the incidence of osteoporotic fractures. The use of more potent analogues of vitamin D, such as calcitriol (Rocaltrol), should be reserved only for those patients who have established vertebral osteoporosis and who generally have more pronounced malabsorption of calcium.
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PMID:Vitamin D metabolism and therapy in elderly subjects. 150 13


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