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)

To determine whether the phosphaturic response to circulating parathyroid hormone (PTH) is exaggerated in patients with familial x-linked hypophosphatemic vitamin D-resistant rickets (FHR), we examined the phosphaturic response to parathyroid extract (PTE) (administered intravenously in the posthypercalcemic state) in two unrelated adult hemizygotes with FHR. In these two patients whose plasma concentration of PTH was normal (determined by radioimmunoassay). neither vitamin D nor phosphate therapy had been given during the past 10 yr. Two normal men and a hypophosphatemic man with intestinal malabsorption, hypocalcemia, and osteomalacia served as control subjects. In all subjects, calcium gluconate was adminstered intravenously from 6 p.m. to 12 midnight at a rate that maintained the concentration of serum calcium at 13-15 mg/100 ml during the administration of calcium. When normocalcemia had recurred the next morning, and the plasma PTH concentration and urinary excretion of cyclic 3', 5'-AMP were reduced. PTE was administered intravenously at successively increasing rates of 0.1, 0.4, and 0.8 U/kg per h, each rate lasting 90 min. Minutes after the initiation of PTE in the affected hemizygotes, fractional excretion of filtered phosphate increased from negligible values to values strikingly greater than those of similarly studied control subjects and plateaued at strikingly greater values throughout further administration of PTE. This phenomenon of exaggerated phosphaturia could not be attributed to volume expansion, decreases in serum concentration of calcium during the study, differences in percent of administered calcium retained, or hemodynamic changes. Only the phosphaturic response to PTE appeared to be exaggerated. At any cumulative dose of PTE, urinary excretion of cyclic 3', 5'-AMP in the hemizogytes was indistinguishable from that of control subjects. The findings in this study suggest that in patients with FHR, circulating PTH is required for the genetically transmitted abnormality to be physiologically expressed as a reduction in net renal reabsorption of phosphate, and that this physiological expression of the genetic abnormality is expressed fully at normal or nearly normal circulating levels of PTH.
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PMID:Exaggerated phosphaturic response to circulating parathyroid hormone in patients with familial X-linked hypophosphatemic rickets. 18 58

Ten patients with vitamin D resistant hypophosphataemic osteomalacia are described. They had hypophosphataemia with a decreased tubular reabsorption of phosphate, malabsorption of calcium and phosphorus, proximal myopathy and extensive osteomalacic changes on iliac crest bone biopsy. The plasma alkaline phosphatase and urine hydroxyproline, however, were raised in only some of the patients. Treatment with 1alpha-hydroxyvitamin D3 in high doses rapidly cured the myopathy, increased calcium and phosphorus absorption and retention and healed the osteomalacia. Phosphorus supplements were not required.
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PMID:Vitamin D resistant hypophosphataemic osteomalacia: treatment with 1alpha-hydroxyvitamin D3. 20 18

Five patients with nutritional osteomalacia or rickets and six children with rickets unresponsive to physiological doses of vitamin D were treated with 1alpha-hydroxyvitamin D3 (1alpha-OHD3). Patients with nutritional osteomalacia responded to 1--2 microgram/day of 1alpha-OHD3. The most striking findings were rises in plasma calcium and, in one case, a decrease in faecal calcium. In some cases there was a rise in plasma phosphorus, alkaline phosphatase remained unchanged. There was radiological healing. In three patients with cystinosis and one with hypophosphataemia and Barrter's syndrome 2 microgram of 1alpha-OHD3 produced healing of rickets. Plasma phosphate rose on treatment, possibly by a suppression of parathyroid activity. The response to such low doses of 1alpha-OHD3 suggests impaired 1alpha-hydroxylation of 25-hydroxyvitamin D in these patients. A patient with intestinal malabsorption was resistant to high doses of 1alpha-OHD3 by mouth but responded to parenteral administration. A boy with osteopetrosis and the biochemical changes of rickets was resistant to large doses of 1alpha-OHD3 presumably because of failure of osseous response.
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PMID:1alpha-hydroxyvitamin D3 in the treatment of nutritional and metabolic rickets and osteomalacia. 20 19

A newborn infant with congenital cytomegalic inclusion disease had spontaneous fractures of the distal radii bilaterally, and involvement of the metaphyseal portions of the humeri, ulnas, femurs, and tibias. The fractures healed promptly without complications under ordinary management. At the present time, one can only speculate on the cause of these lesions. Viral osteomyelitis, osteomalacia secondary to hepatitis and malabsorption and a disturbance of endochondral ossification are all possibilities. There is a need for additional cases with histologic and biochemical studies of the bone lesions in congenital cytomegalic inclusion disease.
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PMID:Osseous lesions and pathologic fractures in congenital cytomegalic inclusion disease: report of a case. 23 93

Typical features of hereditary vitamin D-dependent (pseudovitamin D-deficient) rickets were observed beginning at ages 20 and 5 months in a brother and sister. Both had calcium malabsorption correctable with high doses of 25-hydroxyvitamin D. During periods of hypocalcemia they both manifested secondary hyperparathyroidism with hypophosphatemia and high serum concentrations of endogenously produced 1,25-dihydroxyvitamin D. In each, normalization of serum calcium concentration and resolution of osteomalacia were obtained with continuous administration of high doses of ergocalciferol or high doses of 1,25-dihydroxycholecalciferol. Chemical features of vitamin D deficiency were corrected in the presence of high circulating concentrations of 1,25-dihydroxyvitamin D2, produced endogenously, or of 1,25-dihydroxyvitamin D3, administered by mouth. Serum concentrations of 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, 24,25-dihydroxyvitamin D, and 1,25-dihydroxyvitamin D were normal in five first degree relatives. We conclude that in these five first degree relatives. We conclude that in these siblings, rickets and osteomalacia resulted from a hereditary decreased sensitivity to 1,25-dihydroxyvitamin D at the intestine and perhaps other vitamin D target tissues.
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PMID:A familial syndrome of decrease in sensitivity to 1,25-dihydroxyvitamin D. 23 95

Osteomalacia in a 80-year old woman with malabsorption due to the stagnant loop syndrome is reported. The osteomalacia was associated with bacterial overgrowth in the small intestine and increased bile salt deconjugation. Although the mechanism of osteomalacia in the stagnant loop syndrome remains uncertain, it is suggested that abnormal flora reduce the absorption of vitamin D by deconjugation of bile salts in the lumen of the small intestine.
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PMID:Osteomalacia in the stagnant loop syndrome. 26 35

Severe osteomalacia due to causes other than malabsorption and, where renal function was impaired, disproportionate to the degree of renal failure, is described in 15 adults. Only one was younger than 46 years, the median age being 59 years. The diagnosis was not made for months in most patients. After investigation, the patients were grouped as follows: nutritional three cases, "renal" six cases, hypophosphataemia three cases, neurofibromatosis and primary hyperparathyroidism one each. The last patient was poorly nourished and had taken anticonvulsants and analgesics. Most patients responded well to treatment with calciferol. These cases indicate the need to be aware that osteomalacia may occur in previously healthy middle-aged or elderly subjects.
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PMID:Osteomalacia due to unusual causes presenting in adults. 28 91

Intestinal malabsorption of calcium and the development of osteomalacia in conservatively treated renal failure is explained by a quantitative deficiency of 1,25-dihydroxycholecalciferol, which also contributes to the development of hypocalcaemia. Excess of 25-hydroxycholecalciferol can substitute for this deficiency. The presence and healing of azotaemic osteomalacia is unrelated to the prevailing plasma [Ca] x [P] product. The data suggest that "vitamin D" acts directly on bone mineralisation, but the claim that this apparent effect is normally due to 25-hydroxycholecalciferol is considered unproven. Most of the phenomena of azotaemic osteodystrophy are encountered in simple vitamin D deficiency; as in that condition, deficiency of 1,25-dihydroxycholecalciferol may be of primary significance in causing secondary hyperparathyroidism in renal failure.
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PMID:Vitamin D and the syndromes of azotaemic osteodystrophy. 36 40

Five years following jejunoileal intestinal bypass surgery for obesity, a patient developed debilitating weakness and muscle pain. Osteomalacia was suspected clinically by radiographic and laboratory abnormalities and confirmed by bone biopsy. Malabsorption was documented as well as secondary hyperparathyroidism. Successful treatment of this syndrome with vitamin D and calcium identified a medically reversible disorder which obviated the need for surgical reanastomosis.
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PMID:Osteomalacia and weakness complicating jejunoileal bypass. 43 11

A young female with osteomalacia complicating a blind loop syndrome associated with congenital megaduodenum is described. In this case, the correction of vitamin D malabsorption by administration of antibiotics highlights the role of massive intraluminal bacterial overgrowth from destruction of vitamin D, or decreased unicellar solubilization due to deconjugation of biliary acids. The importance of cutaneous vitamin D synthesis in patients with osteomalacia of gastrointestinal origin is emphasized. The detection of megaduodenum and megaesophagus in the patient's father may be the first report of a familial association of these gastrointestinal abnormalities.
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PMID:Osteomalacia complicating a blind loop syndrome from congenital megaesophagus-megaduodenum. 43 12


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