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

The breath hydrogen test (BHT) was adapted for use in young infants and children. The diagnostic criterion of sugar malabsorption in the BHT was determined by oral administration of 0.5 g/kg of unabsorbable sugar (lactulose) to 21 healthy infants and children. A maximum increase in breath hydrogen less than 0.05 ml/min per m2 was observed in all subjects. A good correlation between results by the BHT and by the ordinary lactose tolerance test was obtained after oral administration of 2 g/kg lactose to 21 healthy infants and children, 2 congenital lactase-deficient infants, and 7 adults. Using this test, 80 healthy Japanese infants and children (aged between one month and 15 years) and 18 adults were examined for lactose malabsorption after a dose of 1 g/kg lactose. All infants and children under 2-years old absorbed lactose completely. The incidence of lactose malabsorption was 30% in 3-year, 36% in 4-year, 58% in 5-year, and 86% in 6-year-old children, 85% in schoolchildren, and 89% in adults. Thus the incidence of lactase deficiency gradually increases with age from 3 years, and about 90% of all normal Japanese adults are lactase-deficient.
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PMID:Breath hydrogen test for detecting lactose malabsorption in infants and children. Prevalence of lactose malabsorption in Japanese children and adults. 47 26

A gas-solid chromatographic system using tandem silica gel and molecular sieve columns is described for the measurement of hydrogen, carbon dioxide, oxygen, and nitrogen in samples of respiratory gases. This system has a detection limit of 2 ppm of hydrogen in a 1 ml sample and can measure 120 ppm H2 and 5% CO2 with relative standard deviations of 1.3% and 1.7%, respectively. Improved sample storage and withdrawal techniques are described that give reproducible values for up to 6 weeks after collection. Finally we show that normalization of breath hydrogen values to an alveolar concentration, using the observed carbon dioxide concentrations, substantially reduces the range and variance of apparent H2 concentrations in human subjects. Normalization eliminates the need for rebreathing or end-expiratory collection techniques and substantially increases the reliability and clinical utility of hydrogen breath measurements in noninvasive tests of carbohydrate malabsorption.
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PMID:Improved gas chromatographic quantitation of breath hydrogen by normalization to respiratory carbon dioxide. 50 Dec 2

On 14 occasions, 1.75 g/kg of body weight of lactose was given in whole milk to preschool children who had significant malabsorption with aqueous lactose solution. The volume of hydrogen excreted in the breath was less after the milk meal. Moreover, the hydrogen response to the nonabsorbable disaccharide, lactulose, was greater with aqueous, solution than with a liquid meal but their difference disappeared when metoclopramide was given with the lactulose: meal. The slower hydrogen production is attributed to slower intestinal delivery of lactose in meals; this phenomenon may account for clinical lactose tolerance often seen in children with demonstrated lactose malabsorption.
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PMID:Reduced rate of breath hydrogen excretion with lactose tolerance tests in young children using whole milk. 57 Dec 2

A non-invasive, interval sampling hydrogen (H2) breath-analysis test for carbohydrate malabsorption was used in a 3 year-old Guatemalan child with severe protein-energy malnutrition (kwashiorkor) and in this relatives: mother half-sister and step-father to examine genetic and nutritional factors in lactose intolerance in young children. Clinical lactose intolerance was present in the patient on admission, and lactose malabsorption, even of 0.88 g per kg of weight, persisted after complete nutritional recobly due to gastric retention of the substrate. Malabsorption of a physiological dose of lactose, 12.5 g, was detected in the mother and step-father while their daughter exhibited normal growth and development and normal lactose absorption at 8 months of age. The H2 breath test proved to be a sensitive, well-tolerated procedure for both adults and young children. Pitfalls, such as delayed gastric emptying, absence of normal bacterial flora, prior use of antibiotics, must be considered in interpreting H2 breath test results in children.
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PMID:Lactose intolerance in protein-energy malnutrition: a clinical case study and family study using a hydrogen (H2) breath-analysis test for carbohydrate malabsorption. 58 60

To assess whether malabsorption of specific sugars is easily detected in a pediatric population by interval measurement of breath hydrogen excretion, hydrogen concentration was determined following administration of oral sucrose to six sucrose-intolerant children with congenital sucrase-isomaltase deficiency and in 16 sucrose-tolerant control subjects. Breath samples were collected by means of a newly devised nasal prong technique not requiring active patient cooperation and suitable for use in all age groups. Breath hydrogen concentrations obtained by samples collected by this method correlated highly (r = 0.94) with the previously validated modified Haldane-Priestley tube method for sampling alveolar air. Identification of sucrose-intolerant individuals was achieved on the basis of hydrogen excretion: peak values, expressed as parts per million above baseline (deltappm), equalled 114 +/- 63 (mean +/- SD) versus 2.4 +/- 3.6 deltappm in control subjects (P = 0.007). Best discrimination between the groups occurred at 90 minutes postingestion. The findings validate this simple method for collection of expired air and demonstrate that breath hydrogen determination permits the noninvasive detection of sucrose malabsorption in children.
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PMID:Sucrose malabsorption in children: noninvasive diagnosis by interval breath hydrogen determination. 65 Mar 40

The time of breath hydrogen appearance (T) after oral lactulose was determined in 98 patients in London who had been to the tropics. Fifty-six controls from three different ethnic groups had no evidence of gastrointestinal disease; 23 had tropical malabsorption, which was severe in 10; and 19 had chronic diarrhoea without malabsorption. Mean T was significantly delayed in patients with tropical malabsorption compared with controls, indicating that their mouth-caecum transit rate was abnormally slow. In six patients with tropical malabsorption who were reinvestigated after treatment a fall in the value for T seemed to parallel clinical improvement. Three patients with diarrhoea due to chronic colonic disease had delayed T. Patients with tropical malabsorption have bacterial colonisation of the small intestine, which is important in the pathogenesis of the disease. Bacterial overgrowth, which sometimes occurs after infective diarrhoea in the tropics and gives rise to tropical sprue, is a result of stasis.
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PMID:Delayed small-intestinal transit in tropical malabsorption. 67 84

Expired hydrogen and blood glucose were measured during an oral lactose tolerance test in 163 children aged between 9 months and 14 years. Lactose malabsorption, defined as an abnormal increase in expired H2 during a lactose tolerance test, was found in 54 children. Of these, 30 were found to be lactose intolerant as the increased expired H2 was accompanied by clinical symptoms. The other 109 children, in whom there was no rise in expired H2, were assumed to have normal lactose absorption. In children with lactose intolerance the increase in expired H2 tended to occur earlier after lactose ingestion than in children with malabsorption. The mean value of the rise in blood glucose was 2.4 mmol/100 ml) in the lactose-tolerant children and 1.0 mmol/1 (18 mg/100 ml) in the lactose-intolerant ones. Although this difference is significant (p less than 0.001), the rise in blood glucose, in predicting the correct diagnosis, was wrong in 13% of cases in the lactose-tolerant group, and wrong in 37% in the lactose-intolerant group (95% confidence limits 9-19% and 22-53% respectively). It is concluded that a rise in blood glucose, whether or not of more that 1.2 mmol/1 (22mg/100 ml) is of little help in differentiating lactose tolerance from intolerance.
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PMID:Improved accuracy of lactose tolerance test in children, using expired H2 measurement. 74 97

The role of vitamin E in human nutrition was studied by investigation of patients with cystic fibrosis (CF) and associated pancreatic insufficiency. Vitamin E status was assessed by measurement of the plasma concentration of the principal circulating isomer, alpha-tocopherol. Results of such determinations in 52 CF patients with pancreatogenic steatorrhea revealed that all were deficient in the vitamin. The extent of decreased plasma tocopherol varied markedly but correlated with indices of intestinal malabsorption, such as the serum carotene concentration and percentage of dietary fat absorbed. Supplementation with 5-10 times the recommended daily allowance of vitamin E in a water-miscible form increased the plasma alpha-tocopherol concentrations to normal in all 19 CF patients so evaluated. Studies on the effects of vitamin E deficiency focused on possible hematologic alterations. An improved technique was developed to measure erythrocyte hemolysis in vitro in the presence of hydrogen peroxide. While erythrocyte suspensions from control subjects demonstrated resistance to hemolysis during a 3-h incubation, all samples from tocopherol-deficient CF patients showed abnormal oxidant susceptibility, evidenced by greater than 5% hemoglobin release. The degree of peroxide-induced hemolysis was related to the plasma alpha-tocopherol concentration in an inverse, sigmoidal manner. The possibility of in vivo hemolysis was assessed by measuring the survival of (51)Cr-labeled erythrocytes in 19 vitamin-E deficient patients. A moderate but statistically significant decrease in the mean (51)Cr erythrocyte half-life value was found in this group. Measurement of erythrocyte survival before and after supplementation of 6 patients with vitamin E demonstrated that the shortened erythrocyte lifespan could be corrected to normal with this treatment. Other hematologic indices in deficient subjects, however, were normal and did not change upon supplementation with vitamin E. It is concluded that CF is invariably associated with vitamin E deficiency, provided that the patient in question has pancreatic achylia and is not taking supplementary doses of tocopherol. Concomitant hematologic effects consistent with mild hemolysis, but not anemia, occur and may be reversed with vitamin E therapy. Patients with CF should be given daily doses of a water-miscible form of vitamin E to correct the deficiency.
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PMID:The occurrence and effects of human vitamin E deficiency. A study in patients with cystic fibrosis. 87 86

An episode of diarrhea causes weight loss and a temporary cessation of growth in infants and children. Diarrhea is accompained by malabsorption of sugars, nitrogen, fats, and micronutrients. The mechanisms by which acute diarrheal disease produce malabsorption have not been studied carefully. The nutritional costs of malabsorption may pose a major threat if diarrhea becomes chronic or recurrent. The hydrogen breath test for carbohydrate malabsorption does not require intubation or blood drawing and can be used in children to help clarify the importance of carbohydrate intolerance in the duration and perpetuation of acute diarrhea and intestinal bacterial overgrowth.
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PMID:Malabsorption associated with diarrhea and intestinal infections. 88 80

The quantity of lactose not absorbed by 4 normal and 6 lactase-deficient subjects was determined by three indirect methods which involved: (1) measurement of pulmonary hydrogen (H2) excretion, (2) pulmonary (14)CO2 excretion, and (3) stool (14)C excretion, after ingestion of 12.5 g of 1-(14)C-lactose and 4 g of polyethylene glycol (PEG). Results were compared with absorption determined directly from the (14)C:PEG ratio of multiple terminal ileal aspirates. The fraction of lactose not absorbed determined by ileal aspiration ranged from 0 to 8% in normals and 42 to 75% in mild-intolerant subjects. Whereas all three indirect methods were useful in qualitatively separating normal from deficient subjects, the quantity of lactose absorbed as determined by H2 excretion correlated most closely with ileal measurements (r = 0.94). Pulmonary (14)CO2 excretion for 24 hr after (14)C-lactose ingestion did not distinguish normal (17 +/- 4% (SEM) of ingested (14)C per 24 hr) from lactase-deficient subjects (21.1 +/- 3%). Likewise, stool (14)C:PEG ratios grossly underestimated malabsorption with less than one-quarter of the nonabsorbed (14)C appearing in the stool. This study suggests that individual differences in susceptibility to diarrhea after milk ingestion by lactase-deficient subjects may be due to differences in the quantity of lactose not absorbed and/or differences in the rate of bacterial metabolism of lactose in the colon. Analysis of ileal fluid collected during passage of the lactose meal indicated that about two-thirds of the osmotic load delivered to the colon consists of endogenous electrolytes. Thus the water load delivered to the colon is about 3 times that calculated to be osmotically held by the nonabsorbed sugar.
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PMID:Quantitative measurement of lactose absorption. 126 65


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