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)

Hypolipidemias can be divided in primary, familial and hereditary forms and symptomatic forms which may accompany other diseases. The primary hypolipidemias (abetalipoproteinemia, hypobetalipoproteinemia and analphalipoproteinemia) are very rare. Severe hypolipidemia can be found in some peoples (e.g. the Masai). This article is chiefly devoted to secondary hypolipidemias such as those associated with malabsorption, malnutrition and maldigestion including protein-losing gastroenteropathy, with liver diseases, endocrine diseases (hyperthyroidism, hirsutism) and anemia. Finally, the hypolipidemias secondary to the formation of autoantibodies against HDL and LDL in M-gradient, carcinoma and rheumatoid arthritis are briefly reviewed.
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PMID:[Hypolipidemias]. 17 Jun 75

A new kindred with asymptomatic hypobetalipoproteinemia is reported. The proband, age 67, differs from previously described cases in several respects: (a) unusually low levels of low density lipoprotein (LDL) cholesterol (4-8 mg/dl); (b) normal triglyceride levels; (c) low levels of high density lipoprotein; (d) mild fat malabsorption; and (e) a defect in chylomicron clearance. On a high-carbohydrate diet his plasma triglyceride levels, instead of rising, actually fell. Turnover of triglycerides in very low density lipoproteins (VLDL) was low (2.8 mg/kg per h). Fractional catabolic rate of LDL protein was just above the normal range (0.655/d) but net turnover was <10% of normal (0.65 mg/kg per d). The half-life of his chylomicrons was 29 min, five times the normal value. Postheparin lipoprotein lipase activity was normal and apolipoprotein C-II, the activator protein for lipoprotein lipase, was present and functional. Apolipoprotein C-III(1), however, was not detected in the VLDL fraction, a finding previously reported in patients with abetalipoproteinemia. Fecal excretion of cholesterol was almost twice normal; total sterol balance was increased by congruent with40%. The unusual features in the proband that distinguish him from previously described cases and from his affected first-degree relatives suggested that, in addition to the basic gene defect affecting LDL metabolism, he might have a second abnormality affecting clearance of chylomicrons and VLDL. The ratio of apolipoprotein E(3) to E(2) in his VLDL fraction was 0.93, just below the lower limit of normal, suggesting heterozygosity for E(3) deficiency. Whether or not this contributes to his hypertriglyceridemia remains to be established.
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PMID:Metabolic studies in an unusual case of asymptomatic familial hypobetalipoproteinemia with hypolphalipoproteinemia and fasting chylomicronemia. 22 46

In the past 5 years, many different mutations in the apolipoprotein (apo) B gene have been described that affect plasma cholesterol levels. More than 20 different mutations in the apoB gene have been shown to cause familial hypobetalipoproteinaemia, a condition characterized by abnormally low plasma concentrations of apoB and LDL cholesterol. Almost all of the mutations are nonsense or frameshift mutations that interfere with the translation of a full-length apoB100 molecule. Many, but not all, of these apoB gene mutations result in the synthesis of a truncated species of apoB that can be detected within the plasma lipoproteins. Familial hypobetalipoproteinaemia heterozygotes are almost always asymptomatic and have LDL cholesterol levels about one-quarter to one-third of those of unaffected family members. Several homozygotes and compound heterozygotes for familial hypobetalipoproteinaemia have been described. In these individuals, the LDL cholesterol levels are extremely low, usually less than 5 or 10 mg dl-1, and the clinical phenotype is variable, ranging from completely asymptomatic to severe problems related to intestinal fat malabsorption. One missense mutation in the apoB gene (an Arg----Gln substitution at apoB amino acid 3500) is associated with very poor binding of apoB100 to the cellular LDL receptor. This syndrome has been designated familial defective apolipoprotein B (FDB). The amino-acid substitution at residue 3500 delays the clearance of LDL from the plasma and results in hypercholesterolaemia. In some Western populations, the frequency of FDB heterozygotes appears to be as high as 1 in 500 individuals.
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PMID:Apolipoprotein B gene mutations affecting cholesterol levels. 161 87

Abetalipoproteinaemia (ABLP) was diagnosed in a brother and sister, 9 and 13 years old, presenting with symptoms of malabsorption during the neonatal period. Both children showed most of the main clinical features of ABLP, including neurological, and ophthalmic symptoms, and mental retardation. Acanthocytosis of erythrocytes was almost complete in the affected children, while in most of the remaining 11 members of their three-generation family, it was found in less than 50% of red blood cells. Absence of apoprotein B and low concentrations of apo A-I and lipids were found only in ABLP-affected children. Among five siblings only the two affected children had ABLP-characteristic lipid storage in enterocytes. The latter features correlated better with clinical symptoms than did the acanthocytosis of erythrocytes.
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PMID:A case of abetalipoproteinaemia in a Polish family. 204 Mar 53

Over the past decade it has become apparent that vitamin E is an essential nutrient for maintaining the structural and functional integrity of the developing human nervous system, skeletal muscle, and the retina. The clinical and histologic resemblance of the human neuromuscular disorder associated with chronic fat and vitamin E malabsorption to that observed in experimental vitamin E-deficient animal models is striking. Because of chronic malabsorption of vitamin E, children with CF, chronic cholestasis, abetalipoproteinemia, and short bowel syndrome are at risk for the development of neurologic deficits caused by vitamin E deficiency. Correction of the vitamin E deficiency state prevents, reverses, or, at least, stabilizes the neurologic dysfunction in susceptible individuals. Advances in stable isotope technology permit study of the hepatic discrimination among the various stereoisomers and forms of vitamin E. Investigations into the cause of the primary form of vitamin E deficiency, the isolated vitamin E deficiency syndrome, promise to delineate the normal physiologic processes involved in absorption, transport, and tissue delivery of vitamin E. Studies in progress are addressing the optimal route and form of vitamin E therapy to be used in each predisposing condition. One major task remaining is to better define the mechanism by which vitamin E deficiency leads to neurologic injury.
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PMID:Vitamin E and neurologic deficits. 217 58

Prevention of vascular disease and acute pancreatitis is the goal of hyperlipidemia treatment. The risk of coronary heart disease (CHD) increases with increasing plasma cholesterol levels because low-density lipoprotein (LDL), the major carrier of cholesterol in the plasma, is atherogenic. High-density lipoprotein (HDL), especially the HDL2 subfraction, protects against CHD. Hypertriglyceridemia, although not an independent risk factor for CHD, is generally accompanied by low HDL cholesterol (HDLch), which may predispose to CHD. Reducing plasma LDL and raising HDL levels are thus goals in preventing CHD. Serum LDL levels may be lowered by reducing saturated fat and cholesterol intake; weight loss may decrease LDL but is more effective in lowering plasma triglycerides and raising HDLch. The percent of total calories from polyunsaturated, monounsaturated, and saturated fats should be less than 10%, up to 10-15%, and less than 10%, respectively. High cholesterol intake increases the flux of cholesterol, which may be harmful to arterial walls, but beyond a certain point does not increase plasma cholesterol levels. Some diets change the composition rather than the level of LDL and apoproteins. Weight reduction and maintenance are the most effective dietary measures to lower plasma triglycerides; omega-3 fatty acids (fish oils) have shown promise in reducing triglyceride but not cholesterol levels. Substitution of starch for sugar lowered triglyceride levels toward normal in hypertriglyceridemia patients. Fasting triglyceride levels rise in all individuals fed high-carbohydrate diets, but the high levels persist in hypertriglyceridemia patients. Weight loss, cessation of cigarette smoking, increased physical activity, good control of diabetes, and moderate alcohol use all raise HDLch levels. Vitamin E deficiency causes neurological sequelae in children with severe malabsorption problems due to abetalipoproteinemia or cholestatic liver disease.
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PMID:Nutritional management of plasma lipid disorders. 255 90

There is increasing evidence that vitamin E is essential for normal neurological function. In abetalipoproteinemia, which is the most severe deficiency state known in man, development of the associated spinocerebellar syndrome can be prevented by early vitamin E therapy. A neurological disorder similar to that seen in abetalipoproteinemia, comprising progressive ataxia, hyporeflexia, and proprioceptive loss, has been described in children and adults with chronic fat malabsorption and vitamin E deficiency. The neuropathological changes in such patients resemble those seen in vitamin E-deficient monkeys. Recent reports suggest that spinocerebellar degeneration may be caused by a selective defect of vitamin E absorption without other evidence of gastrointestinal disease.
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PMID:Vitamin E and the nervous system. 355 52

The hemodynamic effects induced by thiopental and a decrease in blood ionized calcium are uniform. This investigation was undertaken to show a possible decrease in ionized blood calcium during induction of general anesthesia with thiopental. Twenty-four patients aged 19-79 years (median 57) were studied. None had any known parathyroid disease, malabsorption, or chronic renal insufficiency, and none were receiving calcium channel blockers. For the analysis of blood Ca++, pH, and PCO2, blood samples were drawn anaerobically into a heparinized syringe from an i.v. cannula. A special heparin solution was used (S4500 Radiometer, Copenhagen) to avoid the influence of heparin on the Ca++ determination. The initial 2 ml were discarded. No samples were drawn in the first 3 min after removal of the tourniquet. A maximum of 100 ml isotonic saline was infused between the two samplings. The infusion was stopped for at least 30 s before sampling. PCO2, B-Ca++, and pH were measured directly using the ABL 4 (Radiometer, Copenhagen) and the ICA 1 ionized calcium analyzer (Radiometer, Copenhagen). The standard deviation of repeated measurements of B-Ca++ within a short time using the same sample is 0.01 mmol/l on the ICA 1. The samples were drawn just before and 2 min after thiopental injection (median 5.9 mg/kg) was started. The pulse and blood pressure were simultaneously measured. The individual Ca++ measurements are shown in Table 1. The results of the investigation are shown in Table 2.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Effect of thiopental Na on the concentration of calcium ions in blood]. 366 52

Eight infants presented with a malabsorption syndrome, normal fasting triglycerides, hypocholesterolemia (64.3 +/- 10.0 mg/dl), and deficiency of vitamins A and E. Plasma low-density lipoprotein, apolipoprotein B, and apolipoprotein A-I were decreased. After a fatty meal, plasma triglycerides did not increase and chylomicrons could not be identified. Lipoprotein composition was characterized by normal apoproteins, high phospholipids, and low cholesterol. Increased triglycerides were present in low-density lipoproteins. Immunoperoxidase localization of apolipoprotein B on fasting biopsy specimens showed increased staining of the lipid-laden intestinal epithelial cells compared to normals. On electron microscopy after a fat load, the enterocytes contained large numbers of fat particles vesiculating the endoplasmic reticulum. These particles, morphologically similar to chylomicrons, were also present as aggregates of well-individualized lipid droplets within dilated vesicles in the Golgi zone, but were not seen in the intercellular spaces and lacteals. This recessively transmitted condition differs from abetalipoproteinemia and from the homozygous form of hypobetalipoproteinemia and may be caused by a defect in the final assembly of chylomicrons or in the mechanism of their exocytosis.
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PMID:Malabsorption, hypocholesterolemia, and fat-filled enterocytes with increased intestinal apoprotein B. Chylomicron retention disease. 379 76

A male born to first cousins presented at 12 months with hypocalcemic convulsions, rickets, epistaxis due to vitamin K deficiency, and extremely low serum levels of beta-carotene and vitamin A. Liver function was altered moderately (glutamic-oxaloacetic transaminase, 55 U/L; glutamic-pyruvic transaminase, 37 U/L; lactate dehydrogenase, 255 U/L; alkaline phosphatase, 437 U/L). To correct the deficiencies, 8,000 IU vitamin D/day, 10,000 IU vitamin A/day, and intramuscular administration of vitamin K1 were required. At 9 years, he presented signs of neuromuscular affection, and the serum vitamin E level (measured for the first time) was extremely low. Classic lipid malabsorption syndromes (abetalipoproteinemia, chronic cholestasis, mucoviscidosis, coeliac disease, Whipple's disease) were excluded by appropriate examinations. Composition of duodenal bile acids was characterized by undetectable levels of cholic acid metabolites, and only chenodeoxycholic acid metabolites were present. Serum total bile acid concentration was normal, with an atypical low cholic acid/chenodeoxycholic acid ratio and abnormal presence of 3 beta-OH-delta 5-cholenic acid and 6-OH-bile acids. Urinary bile acid composition was also characterized by elevated 6-OH-bile acids. Known enzymopathies of the bile acid synthetic pathway were excluded (cerebrotendinous xanthomatosis, cerebro-hepato-renal syndrome of Zellweger, coprostanic acidemia). Bile acid pool sizes were determined by using stable isotopes: cholic acid pool size [2.90 (N, 32 +/- 16) microM/kg] and chenodeoxycholic acid pool size [10.8 (N, 32.6 +/- 9.9) microM/kg] were extremely low; fractional turnover rates of both bile acids were in a normal range.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Malabsorption of liposoluble vitamins in a child with bile acid deficiency. 379 31


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