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Results for “Lactose Tolerance Test”

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PubMed1995

Lactose malabsorption in Khants in western Siberia.

BACKGROUND: We wanted to estimate the prevalence of selective lactose malabsorption (SLM) in Khants, a small Finno-Ugric population living in Western Siberia who have traditionally consumed no milk in adulthood. METHODS: A total of 80 Khants, aged 8-57 years and living on the middle reaches of the River Ob, were studied. The diagnosis was based on a lactose tolerance test; general malabsorption was excluded by a glucose-galactose tolerance test whenever possible. In six subjects electronmicroscopic examination of the duodenal mucosa was performed. RESULTS: The prevalence of SLM in the Khants was 94%. CONCLUSION: This is the highest prevalence found in the previous Soviet Union.

Adult↗

PubMed2003

Assessment of hypolactasia and site-specific intestinal permeability by differential sugar absorption of raffinose, lactose, sucrose and mannitol.

The sugar absorption test is a non-invasive test for investigating intestinal permeability by simultaneous measurement of four probe sugars. In this study, we evaluated the utility of raffinose, lactose, sucrose and mannitol as probe sugars and calculated their urinary recovery as a percentage of ingested dose (mol/mol) and the recovery ratios of raffinose/mannitol, lactose/ raffinose and sucrose/raffinose. The reference ranges for these ratios, established from 39 healthy volunteers, are 0.005-0.015, 0.13-0.63 and 0.09-0.47, respectively. This sugar absorption test was performed in three patient groups. i) In 109 patients with aspecific gastrointestinal symptoms of whom intestinal histology was studied by duodenal biopsies: the urinary raffinose/mannitol recovery ratio highly correlated with gradation of duodenal damage; the sensitivity and specificity of the raffinose/mannitol ratio for detection of intestinal damage were 93% and 91%, respectively, using a cut-off level of 0.020. ii) In 70 patients in whom intestinal lactase activity was investigated by the lactose tolerance test: the urinary lactose/raffinose recovery ratio provided high diagnostic accuracy for hypolactasia (sensitivity 81% and specificity 89% at a cut-off level of 0.70). In analogy with the lactose/raffinose ratio, we suppose that the sucrose/raffinose ratio can be used as a marker of hyposucrasia. iii) In 40 patients with localized small intestinal damage, Crohn's disease of the ileum (n = 21) and celiac disease with histologically proven duodenal damage (n = 19): the raffinose/mannitol recovery ratio was increased in 100% of patients with celiac disease and in 81% of patients with Crohn's disease; increased lactose/raffinose recovery ratio (hypolactasia) and increased sucrose/raffinose (hyposucrasia) were present in 89% and 95% of celiac patients and 19% and 0% of Crohn's disease patients, respectively. The combination of the raffinose/mannitol ratio and sucrose/raffinose ratio appears to be an indication of the distribution of intestinal damage.

Administration, Oral↗

PubMed1983

Persistence of high intestinal lactase activity in Pakistan.

In order to determine the incidence of persistence of high intestinal lactase activity (PLA) in a Pakistani human population, 53 probands belonging to the Punjabi ethnic group were examined using a lactose tolerance test. The incidence of PLA in the sample was found to be 55%, which has been compared with the incidence in other ethnic groups racially or geographically related to the Pakistani population. Various possible explanations for the fairly high incidence of PLA in the Punjabi ethnic group have been discussed.

Adolescent↗

PubMed1982

Lactose malabsorption in Greek adults: correlation of small bowel transit time with the severity of lactose intolerance.

Using breath hydrogen analysis after 139 mmol (50 g) oral lactose load, we investigated the prevalence of lactose malabsorption in 200 Greek adults and examined the relationship between symptoms and small bowel transit time. One hundred and fifty subjects had increased breath hydrogen concentrations (greater than 20 ppm) after the lactose load. In these individuals peak breath hydrogen concentration was inversely related to small bowel transit time (r = 0.63, 6 = 6.854, p less than 0.001) and the severity of symptoms decreased with increasing small bowel transit time. Lactose malabsorbers with diarrhoea during the lactose tolerance test had a small bowel transit time of 51 +/- 22 minutes (x +/- SD; n = 90) which was significantly shorter than the small bowel transit time of patients with colicky pain, flatulence, and abdominal distension (74 +/- 30, n = 53; p less than 0.001) and both groups had significantly shorter small bowel transit time than that of asymptomatic malabsorbers (115 +/- 21 n:7; p less than 0.001). When the oral lactose load was reduced to 33 mmol (12 g), the small bowel transit time increased five-fold and the overall incidence of diarrhoea and/or symptoms decreased dramatically. These results indicate that the prevalence of lactase deficiency in Greece may be as high as 75% and suggest that symptom production in lactose malabsorbers is brought about by the rapid passage down the small intestine of the malabsorbed lactose.

Adolescent↗

PubMed1995

Effect of mild malnutrition on disaccharidase activity and glucose uptake in intestinal brush border vesicles of growing monkeys.

BACKGROUND: The effect of severe malnutrition has been reported by some workers, but there is a paucity of information on milder forms even though 85% of pre-school children show evidence of mild to moderate malnutrition in India. METHODS: Mild to moderate protein energy malnutrition was induced in 12 monkeys, and 12 were kept as controls. After a 30-40% reduction in body weight as compared with their controls, the animals were killed, and brush border membrane vesicles were prepared from three small parts of the small intestine. Purified vesicles were used for the assay of lactase, sucrase, maltase and glucose uptake in vitro. RESULTS: The activity of lactase, sucrase, and maltase, and uptake of (U-14C)-D-glucose was decreased in all three parts of small intestine, and the lactose tolerance test result was also abnormal in the protein energy-malnourished group. On nutritional rehabilitation, the disaccharidase activities recovered completely. CONCLUSION: This study indicates that even mild to moderate malnutrition decreases the digestion and absorption of carbohydrates throughout the small intestine, and it should not be ignored during the developing stage.

Animals↗

PubMed2002

Lactose intolerance.

Persons with lactose intolerance are unable to digest significant amounts of lactose because of a genetically inadequate amount of the enzyme lactase. Common symptoms include abdominal pain and bloating, excessive flatus, and watery stool following the ingestion of foods containing lactose. Lactase deficiency is present in up to 15 percent of persons of northern European descent, up to 80 percent of blacks and Latinos, and up to 100 percent of American Indians and Asians. A sizable number of adults believe they are lactose intolerant but do not actually have impaired lactose digestion, and some persons with lactase deficiency can tolerate moderate amounts of ingested lactose. A diagnosis of lactose intolerance can usually be made with a careful history supported by dietary manipulation. If necessary, diagnosis can be confirmed by using a breath hydrogen or lactose tolerance test. Treatment consists primarily of avoiding lactose-containing foods. Lactase enzyme supplements may be helpful. The degree of lactose malabsorption varies greatly among patients with lactose intolerance, but most of them can ingest up to 12 oz of milk daily without symptoms. Lactose-intolerant patients must ensure adequate calcium intake.

Calcium, Dietary↗

PubMed1983

Distribution of adult lactase phenotypes in Bedouins and in urban and agricultural populations of Jordan.

Lactose tolerance tests with breath hydrogen determination identified 39 lactose malabsorbers among 162 Jordanian Bedouins (24%), and 111 lactose malabsorbers among 148 subjects from the urban/agricultural zone of western Jordan and Palestine (75%). This highly significant difference supports the hypothesis that milk dependence in nomadic desert populations resulted in selective pressures in favour of the lactase persistence gene. Within the urban/agricultural zone which extends from the desert border in Jordan to the Mediterranean shore, a significant increase in the frequency of lactose malabsorbers (and hypolactasia gene frequencies) from east to west was observed. The suggested genetic cline is problably due to migration from the desert populations to the agricultural zone.

Adolescent↗

PubMed1978

Intestinal lactase deficiency and milk drinking capacity in the adult.

The milk drinking capacity of 200 adults was determined experimentally and the results correlated with their milk drinking habits and intestinal lactase activity as judged by a lactose tolerance test. Of the group 65.5% were found to have deficient lactase activity and 5.3% experienced severe gastrointestinal symptoms with 250 ml of milk; 28.2% with 500 ml; 26.0% with 750 ml; 15.3% with 1000 ml and 25.2% tolerated the latter amount without difficulty. Of the normal individuals, 92.7% tolerated 1000 ml without symptoms. Intestinal lactase activity seemed to be important in determining the extremes of milk ingestion: four or more glasses per day or no milk ingestion, but had little effect in the intermediate pattern of milk consumption. It is concluded that intestinal lactase deficiency has clinical relevance and should be considered when nutritional supplementation with milk is contemplated.

Adolescent↗

PubMed1979

Breath hydrogen test for detecting lactose malabsorption in infants and children. Prevalence of lactose malabsorption in Japanese children and adults.

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.

Adolescent↗

PubMed1983

Prevalence of primary adult lactose malabsorption in Hungary.

Lactose absorption capacity was estimated in 820 apparently healthy, well nourished, Hungarian adults and adolescents (560 females, 260 males, aged 16-54 years) using a field version of the lactose tolerance test with breath hydrogen determination. The test identified 497 lactose absorbers with low, and 323 lactose malabsorbers with high hydrogen excretion 120-150 min after an oral load of 50 g lactose. The prevalence of lactose malabsorption in the general Hungarian sample (n = 535) was 37%. In subgroups from the western and eastern Hungarian plains, frequency of lactose malabsorption reached almost 30%. It tended to be higher in Upper Hungary (ca. 40%) and in subjects stemming from former Hungarian areas in the Carpathian bend. Lactose malabsorption in a Hungarian ethnic subgroup, the Matyo (n = 172), did not differ significantly from that in the general population. Among Romai ("Gypsies", n = 113), the prevalence of lactose malabsorption was significantly higher (56%). Awareness of milk intolerance was significantly more frequent, and severe symptoms of lactose intolerance during the test occurred almost exclusively in lactose malabsorbers.

Adolescent↗

PubMed1999

[Effect of exogenous lactase on the absorption of lactose and its intolerance symptoms].

The objective of this study was to evaluate the effects of lactase on lactose malabsorption and its intolerance symptoms, as well as the available way to improve lactose absorption. Healthy adults with a history of lactose intolerance were screened by 25 g lactose tolerance test. The individuals with higher H2 expired and/or lactose intolerance symptoms were selected as the subjects. Subjects were challenged twice with "400 ml low fat milk" and "400 ml low fat milk + 9000Fcc lactase" separately in 3 days interval. The breath H2 concentration and intolerance symptoms were tested in 4 hours after the challenge. The results showed that exogenous lactase can significantly decrease the incidence of lactose malabsorption (the abnormal expiration of H2 decreased from 100% to 48.9%) and milk intolerance symptoms(from 51.1% to 13.3%). The results from this study demonstrate that lactose malabsorption and intolerance symptoms are resulted from the reduced enzyme activities of individuals, and the exogenous lactase can improve lactose absorption and intolerance symptoms. Lactose supplementation may be an available way to increase the dairy consumption and promote health of people.

Adolescent↗

PubMed1977

Symposium on diarrhea. 3. Investigation of chronic diarrhea.

The practical approach to the investigation of diarrhea must be logical and based on anatomic considerations. The site of the underlying disorder may be determined by the clinical picture, and the logic of investigation will be influenced by the history. Important specific investigation in a case of colonic diarrhea include a careful rectal examination, stool inspection, sigmoidoscopy, rectal biopsy and barium enema study. Colonoscopy has been used, but its role has yet to be defined. In a case of small-bowel steatorrhea or diarrhea quantitative chemical estimation of the daily output of stool fat is useful, and to this investigation is added a small-bowel radiograph series and, if the radiographic findings are abnormal, small-bowel biopsy. Other investigations for small-bowel disease may include the breath test with carbon-14-labelled glycocholic acid, the lactose tolerance test, duodenal aspiration for giardiasis, analysis of serum immunoglobulins and, on occasion, isolation of vasoactive intestinal polypeptide hormone (which may aid the diagnosis of functioning tumours of the pancreas or small bowel). Investigations for pancreatic steatorrhea include abdominal radiography, performance of the secretin test and testing of the response to pancreatic replacement therapy. In some patients it may be useful to use endoscopic retrograde cholangiopancreatography to differentiate pancreatic carcinoma and chronic pancreatitis.

Biopsy, Needle↗

PubMedDate not supplied

Studies on malabsorption in malnourished Pakistani children.

Malnutrition is a common finding in Pakistan especially in children of low socio-economic class. Impairment of digestion and absorption makes the diet inefficient at fulfilling the requirements of the child and leads to malnutrition. Earlier work from this laboratory has shown that feeding a high-protein diet to children suffering from protein-energy malnutrition (PEM) did not improve their condition. In the present study forty-two malnourished children and seventeen control subjects were investigated. They were divided into five groups, i.e. fibrocystic disease of the pancreas (n = 9), coeliac disease (n = 17), lactose intolerance (n = 5), PEM (n = 5) and nonspecific diarrhoea (n = 6) on the basis of history, clinical impression and biochemical findings. They were from 6 months to 12 years of age. The majority of them were suffering from diarrhoea, distension of the abdomen and retardation of growth. All children were physically examined and anthropometric measurements were recorded. Changes in hair in the form of sparseness, dyspigmentation and easy pluckability were observed in all groups. In PEM, 80% of the cases had enlarged livers. All children had reduced weight and height as compared with the control group. Haemoglobin, total protein and serum albumin showed a decrease and the fall was greatest in PEM cases as compared with the control group. The excretion of alpha-amino nitrogen increased in PEM children while hydroxyproline and creatinine levels showed a decrease as compared with the control group. The hydroxyproline index, which signifies the growth rate, was also significantly lower in all groups. Xylose and lactose tolerance tests were performed after an oral dose of xylose or lactose respectively. The xylose concentration after the test dose was reduced with the lowest values in the coeliac disease group as compared with the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Proteins↗

PubMed1992

[Diagnostic and therapeutic problems in Lamblia infections].

A 28-year-old woman complained of chronic diarrhoea of about one year's duration, made worse by taking food. As a lactose tolerance test showed evidence of severe intolerance she was given a lactose-free diet, but this brought no improvement. Duodenal biopsy showed villous atrophy, and in the duodenal juice there were numerous flagellated lamblia. After a single oral dose of 2 g tinidazole the diarrhoea stopped, the lamblia disappeared, and the lactose intolerance and villous atrophy cleared up. Lamblia were also detected in the duodenal juice of a 50-year-old woman, but her infection was much more difficult to treat. Tinidazole (single dose of 2 g), metronidazole (800 mg twice daily for 6 days), ornidazole orally 500 mg twice daily for 10 days and ornidazole intravenously 500 mg twice daily for four days all proved ineffective. However, after a 5-day course of epsilon-9-aminacridine (100 mg three times daily by mouth) the diarrhoea ceased and both vegetative forms and lamblia cysts disappeared. These cases emphasize that lambliasis should be considered as a possible cause of severe chronic diarrhoea even when there is no history of travel abroad and when the symptoms are atypical. Conventional chemotherapeutic agents may be ineffective.

Adult↗

PubMed1998

Role of irritable bowel syndrome in subjective lactose intolerance.

It has been suggested that the symptoms of irritable bowel syndrome (IBS) may be wrongly attributed to lactose intolerance. We examined the relations among IBS, demographic factors, living habits, and lactose intolerance. On the basis of a lactose tolerance test with ethanol, 101 of the 427 healthy subjects studied were lactose maldigesters and 326 were lactose digesters. IBS was diagnosed by means of the Bowel Disease Questionnaire, according to the Rome criteria. The use of dairy products and symptoms experienced after their consumption were recorded. IBS was found in 15% of both the lactose maldigesters and lactose digesters. One-third of the subjects reported intolerance to dairy products containing < or = 20 g lactose. About half of this third were lactose maldigesters and about half were lactose digesters. As explanations for this subjective lactose intolerance, the logistic regression model estimated lactose maldigestion (odds ratio: 10.3; 95% CI: 5.2, 20.4), IBS (4.6; 2.1, 10.1), experience of symptoms other than gastrointestinal ones (2.3; 1.2, 4.5), and female sex (2.1; 1.1, 4.0). Characteristics common to both subjective lactose intolerance and IBS were female sex and the experience of abdominal pain in childhood (P < 0.01). Age, regularity of meals, and the amount of physical activity were not associated with either subjective lactose intolerance or IBS. Of the subjects with IBS, the percentage of lactose maldigesters was the same as in the whole study group (24%) but the number who reported lactose intolerance was higher (60% compared with 27%, P < 0.001). We showed a strong relation among subjective lactose intolerance, IBS, the experience of abdominal pain in childhood, and female sex.

Abdominal Pain↗

PubMed1991

Fat body mass and pharmacokinetics of oral 6-mercaptopurine in children with acute lymphoblastic leukemia.

To evaluate the reasons for the wide variability in bioavailability of orally administered 6-mercaptopurine in children with acute lymphoblastic leukemia, we studied several pharmacokinetic parameters of the drug in 18 affected children receiving remission maintenance therapy, and compared them with their anthropometric data and with the results of intestinal function tests. No correlation was found between estimates of small intestinal absorption (the oral lactose tolerance test and 1 h blood xylose test) and 6-mercaptopurine serum levels. Of the anthropometric measurements considered, only the weight/height percentile (an index of the fat body mass) strongly and linearly correlated with the area under the curve of 6-mercaptopurine. The dose of 75 mg of 6-mercaptopurine/m2 of body surface resulted in higher serum concentrations in children below the 75th percentile than in those with a weight/height ratio exceeding the 75th percentile. In conclusion, these data caution about the risk of underdosing 6-mercaptopurine in overweight children when administering it on the basis of body surface area.

Administration, Oral↗

PubMed1979

Cronkhite-Canada syndrome. A case report and analytical review of 23 other cases reported in Japan.

A case study is presented of a 57-year-old male who showed typical clinical features of Cronkhite-Canada syndrome. Numerous polypoid lesions were found in the stomach, duodenum, ileum, colon and rectum accompanied with characteristic ectodermal changes. Tests indicated a protein-losing gastroenteropathy. Intestinal lactase deficiency was demonstrated by the lactose tolerance test. Scanning electronmicroscopy of the gastric and colonic mucosa revealed prominent secretion of mucoid substances and distortion in the gastric pits and colonic crypts. These abnormal findings were interpreted as having a direct relationship to the loss of protein into the gastrointestinal tract.

Adult↗

PubMed1988

The acceptability of milk and milk products in populations with a high prevalence of lactose intolerance.

1) Most humans, like other mammals, gradually lose the intestinal enzyme lactase after infancy and with it the ability to digest lactose, the principle sugar in milk. At some point in prehistory, a genetic mutation occurred and lactase activity persisted in a majority of the adult population of Northern and Central Europe. 2) Persistence of intestinal lactase, the uncommon trait worldwide, is inherited as a highly penetrant autosomal-dominant characteristic. Both types of progeny are almost equally common when one parent is a lactose maldigester and the other a lactose digester. 3) The incidence of lactose maldigestion is usually determined in adults by the administration in the fasting state of a 50-g dose of lactose in water, the equivalent of that in 1 L of milk. Measurement is made of either the subsequent rise in blood glucose or the appearance of additional hydrogen in the breath. It is also sometimes identified by measuring lactase activity directly in a biopsy sample from the jejunum. For children the test dose is reduced according to weight. Depending on the severity of the lactase deficiency and other factors, the test dose may result in abdominal distention, pain, and diarrhea. 4) The frequency of lactose maldigestion varies widely among populations but is high in nearly all but those of European origin. In North American adults lactose maldigestion is found in approximately 79% of Native Americans, 75% of blacks, 51% of Hispanics, and 21% of Caucasians. In Africa, Asia, and Latin America prevalence rates range from 15-100% depending on the population studied. 5) Whenever the lactose ingested exceeds the capacity of the intestinal lactase to split it into the simple sugars glucose and galactose, which are absorbed directly, it passes undigested to the large intestine. There it is fermented by the colonic flora, with short-chain fatty acids and hydrogen gas as major products. The gas produced can cause abdominal distention and pain and diarrhea may also result from the fermentation products. 6) Among individuals with incomplete lactose digestion, there is considerable variation in awareness of lactose intolerance and in the quantity of lactose that can be ingested without symptoms. A positive standard lactose test is not a reliable predictor of the ability of an individual to consume moderate amounts of milk and milk products without symptoms. In usual situations the quantity of lactose ingested at any one time is much less than in the lactose-tolerance test.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗