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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The exocrine pancreas is a gland which secretes water, enzymes and electrolytes into the intestinal lunar. These enzymes for the normal digestion of food and a deficit, whether due to a seduced secretion (chronic pancreatitis, cystic fibrosis), or dysfunction in the chronology of their secretion (following truncal vagotomy) will cause malabsorption which often develops, in clinical terms, into malnutrition sometimes this functional deficit is secondary to other pathologies or surgical operations which alter the digestive tract physiology, preventing the correct combination of nutrients and pancreatic enzymes together with the biliary salts. The outcome is malabsorption, mainly of fast and fat soluble vitamins. As the onset is slow and forms part of a chronic, pathology, diagnosis is difficult, for which reason it is included in the general group of malabsorption due to pancreatic insufficiency or surgical sequelae, finally resulting in pancreatic failure or problems following surgery. The purpose of this publication is to review one by one all the situations in which there is an alteration in the function of the pancreatic enzymes, with emphasis on cases in which a defined malabsorption syndrome will result, and in which the prescription of exogenous pancreatic enzymes will imposiue the picture.
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PMID:[Exocrine pancreatic insufficiency. Organic and functional deficiencies]. 157 5

Cystic fibrosis (CF) is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). The principal manifestations of CF include increased concentration of Cl- in exocrine gland secretions, pancreatic insufficiency, chronic lung disease, intestinal blockage and malabsorption of fat, and male and female infertility. Insight into the function of CFTR can be gained by correlating its cell-specific expression with the physiology of those cells and with CF pathology. Determination of CFTR messenger RNA in rat tissues by in situ hybridization shows that it is specifically expressed in the ductal cells of the pancreas and the salivary glands. In the intestine, decreasing gradients of expression of the CFTR gene are observed on both the crypt-villus and the proximal-distal axes. This expression is consistent with CFTR being responsible for bidirectional Cl- transport, secretion in the intestinal crypts and reabsorption in the silivary gland ducts, and suggests that in these tissues CFTR functions as a regulated Cl- channel. In the lung, a broad band of hybridization includes the mucosa and submucosa of the bronchi and bronchioles. In the testis, CFTR expression is regulated during the cycle of the seminiferous epithelium. Postmeiotic expression is maximal in the round spermatids of stages VII and VIII, suggesting that CFTR plays a critical role in spermatogenesis and that deficiency of this function contributes to CF male infertility.
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PMID:In vivo cell-specific expression of the cystic fibrosis transmembrane conductance regulator. 171 39

Intrinsic factor is produced by the gastric parietal cell. Its secretion is stimulated via all pathways known to stimulate gastric acid secretion: histamine, gastrin, and acetylcholine. There is, however, a different mode of secretion for both substances: atropine, vagotomy, and H2 receptor antagonists inhibit both intrinsic factor and acid secretion, but secretin and the hydrogen-potassium ATPase antagonist omeprazole have no effect on intrinsic factor while substantially reducing acid secretion. Cobalamin in food is bound to animal protein. Cobalamin deficiency due to inadequate dietary intake is rarely seen in extreme vegetarians (vegans). In the stomach cobalamin is liberated from its protein binding by peptic digestion and bound to R-proteins. Hypochlorhydria or achlorhydria, whether medically induced or not, may impair cobalamin uptake. The cobalamin-R-protein complex is split by pancreatic enzymes in the duodenum, where cobalamin is bound to intrinsic factor. Pancreatic insufficiency may lead to cobalamin deficiency. Lack of intrinsic factor is the commonest cause of cobalamin deficiency; very rarely, aberrant forms of intrinsic factor are produced, but the clinical syndrome is similar. Gram-negative anaerobe bacteria bind the cobalamin-intrinsic factor complex, and bacterial overgrowth of the small intestine diminishes cobalamin resorption. Parasitic infections with fish tape-worm and Giardia lamblia are also associated with cobalamin malabsorption. The cobalamin-intrinsic factor complex binds to the ileal receptors in the terminal ileum. Cobalamin absorption may be impaired after resection or by diseases affecting more than 50 cm of the terminal ileum, such as Crohn's disease, coeliac disease, tuberculosis, lymphoma or radiation. There is clearly a wide diversity in the aetiology of cobalamin deficiency, which requires a versatile diagnostic approach.
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PMID:Intrinsic factor secretion and cobalamin absorption. Physiology and pathophysiology in the gastrointestinal tract. 177 33

Vitamin B12 malabsorption was reported earlier to occur in patients with exocrine pancreatic insufficiency, and pancreatic extracts were shown to improve the absorption of vitamin B12. We investigated serum levels of vitamin B12 and serum folate in patients with chronic pancreatitis and different degrees of pancreatic insufficiency. 137 patients (84 males, 53 females, age 34-72 years) with chronic pancreatitis (C.P.) were included in the study. 123 of 137 (89.8%) patients had a pathologic pancreatic function test result, classified into mild (n = 24), moderate (n = 61) or severe (n = 38) insufficiency. The normal range of serum vitamin B12 and folic acid was established in 58 healthy controls and was found to be 190-1020 pg/ml for serum vitamin B12 and 2.4-16.1 ng/ml for folic acid. 7 patients (5.7%) with C.P. had vitamin B12 serum levels below 190 pg/ml; 4 of these had severe and 3 had mild or moderate exocrine pancreatic insufficiency. However there was no overall correlation between the degree of pancreatic insufficiency and vitamin B12 values. Serum levels of Vitamin B12 were 512 +/- 48 pg/ml in mild, 493 +/- 52 pg/ml in moderate and 428 +/- 45 pg/ml in severe exocrine insufficiency. Serum folic acid below 2.4 ng/ml were present in 5 patients (3.6%). Folic acid serum levels were 8.34 +/- 0.76 ng/ml in mild, 6.34 +/- 0.52 ng/ml in moderate and 7.45 +/- 0.53 ng/ml in severe exocrine insufficiency. We conclude that vitamin B12 deficiency is a rare finding in chronic pancreatitis and does not strictly depend on the degree of exocrine pancreatic insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vitamin B12 and folic acid deficiency in chronic pancreatitis: a relevant disorder? 204 78

A 6-year-old girl with severe malabsorption resulting from pancreatic insufficiency, and with hypocholesterolemia is described. 57% of her plasma cholesterol was found in high density lipoprotein (HDL), 95 mg/dl, while only 25 mg/dl was in the low density lipoprotein (LDL) fraction. Platelet aggregation in platelet-rich plasma, in response to both collagen and ADP, were substantially reduced (by 54 and 33%, respectively) in comparison with normal controls. However, after removal of plasma and washing the isolated platelets, they were not hypoactive. These results suggest that the plasma environment affects platelet activity, and confirms our in vitro results on the enhancing and inhibiting effects of LDL and HDL, respectively, on platelet activity.
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PMID:[Platelet hypoactivity in hypocholesterolemia]. 206 15

The present study attempts on one hand to study the metabolic disorders which may present themselves in the gastrectomized patient, such as the malabsorption of fat, vitamin B12, folic acid and iron as well as the possible correlation between steatorrhea and the presence of exocrine pancreatic insufficiency. For this purpose a group of 71 patients have been studied who have undergone a subtotal gastrectomy (70.42%) or total (29.58%) in the General Surgery Services of Elche. The results obtained show the presence of ferropenic or megaloblastic anemia in 61.97% of the group, serious steatorrhea in only 3 patients (4.22%) and calciumphosphorous metabolism alterations appeared in 21.13%. With this we conclude that anemia is the most frequent ferropenic alteration in the gastrectomy patient; steatorrhea does not seem to be produced exclusively by the presence of exocrine pancreatic insufficiency and bone alterations in the gastrectomized patient appear in an insidious manner, being more a question of biochemical alterations than actual clinical lesions.
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PMID:[Metabolic disorders in the gastrectomized patient]. 209 Jan 70

The essential effects of Tocopherol are based on its antioxidative capacity. Tocopherol, however, is just one in a group of antioxidants, which are important for the organism. Established indication for therapeutical application of vitamin E in infancy is only vitamin-E-malabsorption in connection with chronic cholestasis, pancreatic insufficiency (cystic fibrosis) and short bowel syndrome. In emergency therapy vitamin E is suggested with high dosage in case of shock lung and haemolytic-uraemic syndrome. Positive effects of daily vitamin E application in connection with prophylaxis of retinopathy prematurity, bronchopulmonary dysplasia and intraventricular encephalorrhagia of premature infants of severe underweight are not established. Very questionable therapeutic or prophylactic efficiency is opposed to the risk of higher incidence of severe complications in caring for premature infants of severe underweight, such as enterocolitis necroticans and neonatal septicaemia.
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PMID:[The use of vitamin E in childhood]. 209 6

The 14C-triolein breath test, a recognised index of fat absorption, and the p-aminobenzoic acid (PABA) test, a 'tubeless' test of exocrine pancreatic function, have both been widely used in the diagnosis of malabsorption and exocrine pancreatic insufficiency. This study evaluates the potential of a combination of both tests in the investigation of fat absorption and exocrine pancreatic function. Combination of the tests has become technically feasible because of the introduction of high pressure liquid chromatography as the preferred method of analysis for PABA, and use of p-aminosalicylic acid (PAS) as the marker for PABA absorption and metabolism. We studied 25 healthy subjects, 11 patients with exocrine pancreatic disease and 12 patients with gastrointestinal disease. The combined test identified subjects with reduced fat absorption and distinguished subjects with exocrine pancreatic insufficiency from those with an intestinal cause of fat malabsorption. The test could be completed in 7 h and had high patient acceptability. These findings suggest that the combined 14C-triolein breath test and PABA test can be used as a non-invasive, 1-day investigation of fat absorption and exocrine pancreatic function.
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PMID:Combined single day 14C-triolein breath test and PABA test in the diagnosis of malabsorption. 210 21

The occurrence of chronic mucocutaneous candidiasis accompanying polyglandular autoimmune syndrome type I is reported in a female aged 13. Apart the candidiasis, since the age of 3, she had convulsions beginning at 6, cataract at 9, teeth abnormalities, and basal ganglia calcifications. Laboratory data confirmed the diagnosis of hypoparathyroidism. This picture was accompanied by intestinal malabsorption, leading to a state of progressive malnutrition, with intense hypoalbuminemia and anemia. Although the pathophysiology of malabsorption, in these cases, is still not clear, the therapeutic response to pancreatin, in the present case, suggested pancreatic insufficiency, reinforced by the normal d-xylose test and the small intestinal biopsy with inexpressive result.
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PMID:[Polyglandular autoimmune type I syndrome with hypoparathyroidism, chronic mucocutaneous candidiasis and intestinal malabsorption]. 213 67

Vitamin B12 can bind two carrier proteins in the digestive tract, haptocorrin (R binder) and intrinsic factor, but only its binding to intrinsic factor allows its absorption. A malabsorption of vitamin B12 is observed in about 30% of adult patients with exocrine pancreatic insufficiency, using the Schilling test. None of the hypotheses that have tried to explain this malabsorption are entirely satisfactory. A failure to degrade haptocorrin can prevent the binding of vitamin B12 to intrinsic factor. It has also been suggested that pancreatic secretion could modify the structure of intrinsic factor, enabling the uptake of the vitamin B12-intrinsic factor complex by the ileum. Other factors can also affect the binding of vitamin B12 to intrinsic factor, such as the gastric pH and bile. The Schilling test is abnormal in nearly all cases of cystic fibrosis. One explanation could be the gastric hyperacidity observed in this disease. Despite the frequency of abnormal Schilling tests, vitamin B12 deficiency is very rare in cases of exocrine pancreatic dysfunction, in adults as well as in children with cystic fibrosis. The assimilation of this vitamin with a tracer included in food instead of the crystalline labeled cobalamin used in the Schilling test remains to be investigated.
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PMID:Malabsorption of vitamin B12 in pancreatic insufficiency of the adult and of the child. 223 67


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