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)

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

Osteodystrophy frequently accompanies severe childhood hepatobiliary disease. Proposed causes include malabsorption of vitamin D and calcium, and diminished 25-hydroxylation of vitamin D. Two children, ages 23 and 35 months, with radiographic and biochemical evidence of rickets with extrahepatic biliary atresia, were treated with 1,25-dihydroxyvitamin D3. The minimal effective therapeutic dose and efficacy of 1,25-(OH)2D3 in the treatment of rickets associated with severe childhood hepatic disease were determined. Oral 1,25-(OH)2D3 was ineffective at doses of 0.10 microgram/kg/day. Parenteral doses of 0.20 microgram/kg/day effectively produced radiographic, bone mineral (photon absorptiometric), and biochemical evidence of healing. The need for four times the physiologic dose of 1,25-(OH)2D3 by the parenteral route suggested enhanced catabolism of, or end-organ resistance to, 1,25-(OH)2D3 in our patients with severe cholestatic liver disease treated with phenobarbital.
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PMID:1,25-Dihydroxyvitamin D3 in childhood hepatic osteodystrophy. 44 53

Mild rickets was present in 7, and 3 others with severe bone disease developed widespread skeletal demineralization and multiple fractures. The intake of vitamin D was apparently loosely related to the severity of the osteodystrophy. The latter however, was closely linked to both the serum inorganic phosphate and the calciumXphosphate product. The serum calcium was directly related to the infant's gestational maturity, hypocalcaemia being present in those born before 35 weeks. Pathogenetic factors have probably included reactive hyperparathyroidism and nutritional deprivation associated with preterm delivery. Five of the infants who had biliary atresia developed radiological evidence of osteoporosis from about twelve months of age. This may be related to protracted calcium malabsorption, but its true nature remains to be elucidated.
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PMID:The osteodystrophy of prolonged obstructive liver disease in childhood. 125 25

The prevalence, type, and factors that may influence the development of bone disease in primary biliary cirrhosis, have been investigated in 20 consecutive patients, who, in addition to liver function tests and mineral and vitamin D metabolism studies, were submitted to a transiliac bone biopsy after tetracycline double-labeling for quantitative histomorphometric examination. Intestinal calcium absorption was also assessed in 16 patients. Seven patients (35%) had reduced bone volume and were considered osteoporotic. Three also had bone mineralization impairment, but did not have criteria for osteomalacia. Bone formation was depressed in 15 patients, and bone resorption was low or normal in 19 cases. Eroded surfaces were reduced in all osteoporotic patients. Duration of primary biliary cirrhosis was significantly longer in patients with osteoporosis (6.3 +/- 0.6 yr) than in those without osteoporosis (2.6 +/- 0.6, p = 0.004). Moreover, osteoporosis was more prevalent in postmenopausal women, and in those who had intestinal calcium malabsorption, which was present in 80% of osteoporotic patients but in only 18% of nonosteoporotic patients (p = 0.03). Osteoporosis and mineralization bone impairment were unrelated to the severity of cholestasis. 25-Hydroxyvitamin D was significantly lower in those patients with intestinal calcium malabsorption. The results of this study indicate that osteodystrophy in primary biliary cirrhosis is characterized mainly by "low-turnover" osteoporosis, which is related to the duration of the liver disease, postmenopausal condition, and calcium malabsorption.
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PMID:Factors influencing the development of metabolic bone disease in primary biliary cirrhosis. 222 Jul 29

The intestinal absorption of calcium is often depressed in patients with chronic renal insufficiency. Furthermore, the malabsorption of calcium and the osteodystrophy which occur in association with chronic renal disease are often "resistant" to vitamin D; the basis for this resistance remains uncertain however. Recent studies by others have emphasized the role of an abnormality in the metabolism of vitamin D in accounting for the alterations in the calcium absorption and the apparent vitamin D-resistance which accompany the uremic syndrome. The present studies with an experimentally uremic animal model demonstrate a defect in the active transport of calcium by duodenal gut sacs in vitro. This abnormality is not due to the semistarvation associated with renal insufficiency and cannot be corrected by the administration of physiologic amounts of vitamin D(3): it is reversed by massive doses of the vitamin. Neither the metabolism of vitamin D(3) nor the levels of calcium binding protein activity in the duodenal mucosa are affected by renal insufficiency under the conditions employed in the present studies. The results of the present studies strongly suggest that in addition to the recently proposed mechanism involving an interference with the metabolism of vitamin D renal insufficiency also affects the cellular mechanisms for calcium transport in a manner which, while opposite in direction to that of vitamin D, is independent of a direct interaction with the vitamin or its metabolites.
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PMID:Effect of renal insufficiency on the active transport of calcium by the small intestine. 542 27

To investigate the pathogenesis of hepatic osteodystrophy (HOD) in parenchymal liver disease, we developed a laboratory model in animals using carbon tetrachloride (CCl4) and thioacetamide. Biochemical and histological parameters in the model were measured. In rats with both chronic non-cirrhotic liver injury and CCl4-induced cirrhosis, tibial bone volume was significantly lower than in controls. In CCl4-treated cirrhotic rats, the osteoid volume decreased while the urinary calcium/creatinine ratio increased. In all CCl4-treated rats, bone volume was significantly correlated with both the serum albumin concentration and the number of goblet cells reflecting intestinal villous atrophy. The serum concentration of vitamin D metabolites was not correlated with bone volume. Whole body retention of 47Ca was significantly lower in CCl4-treated cirrhotic rats than in controls. Furthermore, the bone volume in thioacetamide-treated cirrhotic rats was significantly lower than in controls. These data demonstrate that chronic parenchymal liver injury itself causes osteoporosis (i.e. HOD) due to a combination of low bone formation rates and high resorption rates, that HOD begins at the stage of chronic non-cirrhotic liver injury, that bone volume in HOD parallels liver damage and that the principal pathogenesis of HOD seems to be intestinal Ca malabsorption due to lower serum albumin and villous atrophy, while serum levels of vitamin D metabolites have little influence on the pathogenesis of HOD.
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PMID:Bone changes and mineral metabolism disorders in rats with experimental liver cirrhosis. 903 34

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.
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PMID:Hepatic osteodystrophy in chronic cholestasis: evidence for a multifactorial etiology. 1200 Apr 70

Primary biliary cirrhosis is a chronic liver disease of unknown etiology, characterized by inflammation and destruction of the intrahepatic biliary ducts, resulting in chronic cholestasis and eventually cirrhosis. The main clinical manifestations consists of pruritus, jaundice, xanthomas, and the consequences of intestinal malabsorption, including vitamin deficiencies and osteodystrophy. Treatment of PBC is addressed at preventing or relieving the symptoms and clinical consequences of chronic cholestasis, and also at correcting the bile duct abnormalities by specific treatments. Pruritus is treated with cholestyramine, but in some cases other drugs, such as rifampicin or opioid antagonists are needed. Bisphosphanates are effective for increasing bone mass in osteopenic patients. Vitamin D and cAlcium supplements are also recommended, particularly in patients with severe cholestasis. Ursodeoxycholic acid (UDCA) has become the standard treatment (13-15 mg/kg/day), resulting in marked relieving of cholestasis. UDCA also prevents the histological progression of the disease, although the effects on survival are less apparent. Small trials of combination therapy using UDCA with methotrexate, colchicine, or prednisone, have been reported but have not shown any increased efficacy over UDCA therapy. Liver transplantation is the only treatment available when cholestasis progresses, with very good survival rates.
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PMID:Treatment of primary biliary cirrhosis. 1649 78

It is well known that insulin resistance affects osteodystrophy, and there is an important relationship between insulin resistance and hepato-biliary disease. It is also well known that hepato-biliary and pancreatic disease is associated with osteodystrophy. In the present review, we describe the mechanism of diabetes and osteodystrophy due to hepato-biliary and pancreatic disease. Hepatic osteodystrophy is associated with malabsorption, abnormalities of vitamin D metabolism, inflammatory cytokines, receptor activator of NF-kappaB ligand, and insulin-like growth factor-1. In particular, tumor necrosis factor-alpha and malabsorption are important factors for viral and alcoholic hepatitis, respectively. Malabsorption due to steatorrhea is important for cholestatic disease and chronic pancreatitis. A greater focus on non-alcoholic steatohepatitis (NASH) and further investigations to clarify the relationship between osteodystrophy and NASH are needed.
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PMID:[Hepato-biliary and pancreatic disease and osteodystrophy]. 1972 Nov 98

Improved survival of orthotopic liver transplantation (OLT) has shifted the focus of patient care to quality of life, including prevention and treatment of pre- and post-transplant complications. End-stage liver failure affects bone length and strength, causing growth failure and hepatic osteodystrophy. Growth failure affects 60% of children assessed for OLT. Optimization of nutrition may prevent further stunting of growth before OLT but is rarely successful. Catch-up growth is observed following steroid withdrawal usually from 18 months post OLT. Whether growth hormone treatment would benefit the 20% of children who fail to regain normal height needs to be tested in randomized controlled trials. Hepatic osteodystrophy in children comprises vitamin D deficiency rickets, low bone mass and fractures caused by malnutrition and malabsorption. Vitamin D deficiency should be treated aggressively with cholecalciferol (D2) or ergocalciferol (D3). The active vitamin D metabolites alphacalcidol or calcitriol are used to increase calcium absorption from the gut but do nothing to replace vitamin D stores. Children before and after OLT have an increased prevalence of fractures of 10-13% and 12-38%, respectively. Most fractures are vertebral, and are related to low spine BMD. They often occur asymptomatically but may also cause chronic pain and later scoliosis. The main risk groups are infants with cholestatic liver disease, and adolescents with later OLT and greater BMI. Fracture prediction in these children is limited. OLT also bears the risk of avascular bone necrosis (4%), and development of scoliosis (13-38%). This paper reviews the literature and presents preventative and therapeutic strategies to improve bone length and strength.
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PMID:Growth and bone health in chronic liver disease and following liver transplantation in children. 2052 40


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