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Mast cells and eosinophils in the jejunal mucosa of patients with intestinal cow's milk allergy and celiac disease of childhood.

We counted the number of granulated mast cells with high iron diamine staining, and the number of eosinophils with hematoxyline-eosin staining, in the lamina propria of the jejunum in 12 untreated patients with intestinal cow's milk allergy (CMA), 47 with celiac disease (CD), and 14 controls. A decreased number of mast cells and an increased number of eosinophils were found in 58% of patients with CMA, and in 60% of those with CD. The number of mast cells showed a significant positive correlation with the villous height, and the number of eosinophils a negative correlation with both the villous height, and the number of mast cells. Appropriate dietary treatment resulted in a rise in the number of granulated mast cells and a decrease in the number of eosinophils in both patient groups.

Adolescent↗

Lactose malabsorption is not a cause of diarrhea during phototherapy.

Lactose malabsorption is not a cause of diarrhea during phototherapy. Jaundiced neonates under phototherapy develop diarrhea or loose stools during the treatment. These phenomena were attributed to an induced lactase deficiency caused by bilirubin breakdown products. We investigated lactose malabsorption in 59 neonates--29 normals and 30 jaundiced under phototherapy. Five-hour hydrogen breath tests were performed. Preprandial and postprandial (at 30, 60, 120, 180, 240, and 300 min) expired air samples were analyzed for hydrogen. Ten controls and five jaundiced neonates had positive hydrogen breath tests. Eighteen controls and 16 neonates under phototherapy had preprandial hydrogen (concentrations above 5 ppm). In our hands, lactase deficiency and lactose malabsorption were not induced by phototherapy. Lactase deficiency is therefore not the cause of diarrhea associated with phototherapy.

Breath Tests↗

Value of breath hydrogen analysis in management of diarrheal illness in childhood: comparison with duodenal biopsy.

Breath hydrogen tests were carried out on 157 children either because they had chronic diarrhea or because they were on disaccharide-free diets. Lactose malabsorption was common in patients with postgastroenteritis syndrome (43%), and sucrose malabsorption was readily detected in patients with congenital sucrase-isomaltase deficiency. Secondary sucrose malabsorption and small bowel bacterial overgrowth were also detected. In predicting clinical response to dietary change, the breath hydrogen test, as we perform it, was clearly the most specific and sensitive and had a predictive accuracy of 96%. Duodenal biopsy results obtained from 48 of the children gave a 23% incidence of misleading disaccharidase results (16.7% falsely normal, 6.3% falsely abnormal), but biopsy remains vital in the diagnosis of congenital sucrase-isomaltase deficiency. False negative breath hydrogen results were obtained on occasions (4%) but in most instances were related to recent antimicrobial therapy or failure of the breath test mechanics (e.g., vomiting, length of sampling).

Biopsy↗

Lactase insufficiency revisited.

The definition of "insufficient" small bowel lactase activity varies greatly among authors. The present study is aimed at redefining lactase insufficiency by comparing intestinal lactase activity and results of the lactose breath hydrogen test. Primary "insufficient" lactase activity was considered to be present when a child with a normal small bowel histology showed lactose malabsorption as measured by the lactose breath hydrogen test. The lactase activity of 22 "normal" children ranged from 0.77 to 4.57 U/g wet weight, while five children showed primary lactase insufficiency as defined above. Small bowel lactase activity in the latter patients was less than 0.74 U/g wet weight. Sucrase and maltase activities were similar in both groups of patients. We conclude that children with a normal small bowel histology should be considered to have primary lactase insufficiency when small bowel lactase activity is below 0.75 U/g wet weight.

Adolescent↗

Absorption and tolerance of lactose in infants recovering from severe diarrhea.

Nineteen infants were challenged during their convalescence from severe diarrhea with a lactose-containing meal. Twenty-four hour intake, pre- and post-challenge breath H2 levels, clinical responses, and growth were measured at approximately biweekly intervals for 3 months beginning 1 month after hospital discharge. Ten lactose-tolerant infants were assigned randomly to receive one of two formulas similar in composition except for carbohydrates: lactose (Group L) (n = 6) and sucrose (Group S) (n = 4). Infants in Group L had greater intakes and growth rates during the initial 15 days of the study. No difference in weight for age z-scores was detected between groups at the end of the observation period. Infants in Group L had higher baseline and peak breath H2 levels indicating greater colonic carbohydrate fermentation than infants in Group S: however, breath H2 levels were not predictive of tolerance to lactose-containing meals. Carbohydrate absorption by infants in Group S appeared to exceed that of infants in Group L. Thus, colonic fermentation of malabsorbed carbohydrate may have prevented diarrhea and allowed acceptable rates of catch-up growth.

Diarrhea, Infantile↗

The cut-off criterion for a positive hydrogen breath test in children: a reappraisal.

Seventy-three preschool children with adequate nutritional status underwent interval-sampling, 3-hour breath-hydrogen carbohydrate absorption tests after consuming either 240 ml of intact milk (containing 12 g of lactose) or the same volume of milk with 90-95% of its lactose prehydrolyzed in vitro (containing less than 1 g lactose, with the remaining sugar as glucose and galactose). Results were examined in a reappraisal of the cut-off criterion for the rise of breath H2 concentration signifying biologically incomplete absorption. If the greater than or equal to 10-ppm criterion advocated by some investigators is used, 83% of our subjects would have been classified as incomplete lactose digesters and 30% would have their tests with the monosaccharide-rich milk classified as positive. With the greater than or equal to 20 ppm criterion used in our laboratory and others, the prevalence of lactose maldigestion in the sample becomes 60% and only 4% of subjects have apparent monosaccharide absorption, 96% having a rise below the cut-off level with prehydrolyzed milk. At least in Guatemalan preschoolers, the 20-ppm criterion for a positive breath H2 test provides a superior specificity-sensitivity balance and more reasonable diagnostic conclusions.

Animals↗

Breath hydrogen test in children with giardiasis.

Respiratory hydrogen excretion was measured in 50 children with giardiasis in order to study lactose absorption. Samples of expired air were collected before and after the children drank 250 ml of whole cow's milk. The test was repeated after successful elimination of Giardia lamblia following treatment with tinidazol. The number of children showing a rise in breath hydrogen excretion greater than 20 ppm decreased from 33 (72%) before treatment to 20 (44%) after treatment. This study permits the conclusion that the presence of G. lamblia in the intestine might interfere with optimum lactose absorption.

Animals↗

Lactose malabsorption and small-intestinal lactase in normal Chinese children.

A total of 852 healthy Chinese children from 1 month to 14 years of age were investigated for lactose malabsorption using the breath hydrogen test. A lactose load of 2 g/kg was administered to 528 children and 1 g/kg to another 324 children. The incidence of lactose malabsorption was significantly different among various age groups and between the two different lactose dosages. While the incidence of malabsorption increased strikingly from the age of 3 to the age of 5 years, the age effect remained constant after the age of 6 years. The lactose load of 2 g/kg induced a higher incidence of malabsorption in study subjects than 1 g/kg did, and the dose effect increased for those aged below 5 years and decreased above 5 years. Small-intestinal lactase was also studied in 34 children aged from 2 months to 15 years. The lactase activity was highest in children 2 years old or younger, gradually decreasing with increasing age. In conclusion, lactase activity in Chinese children decreases gradually after 3 years of age, a finding that correlates well with the results of the breath hydrogen test.

Adolescent↗

Lactose malabsorption and recurrent abdominal pain in Italian children.

The role of lactose malabsorption (LM) was investigated in 32 children (mean age 8.13 +/- 2.46 years) with recurrent abdominal pain (RAP). LM was detected in 75% of them by a lactose breath hydrogen test (LBHT) after a 2-g/kg (max 50-g) load. Of the 18 malabsorbers who participated in a 3-month lactose-free diet (LFD), 14 were judged "improved" and reported lower pain frequency (p less than 0.001). The malabsorbers who improved versus the not improved had comparable past lactose ingestion but were distinguishable on the basis of their lactose absorption capacity (0.36 vs. 0.81 g/kg; p less than 0.01), as subsequently determined by multiple LBHTs with 25-, 12.5-, and 6-g loads. The ratio between past lactose ingestion and lactose absorption was 1.89 in the improved and 0.55 in the not improved groups (p less than 0.01), retrospectively indicating lactose as a possible cause of the symptoms in the improved group. The reintroduction of lactose in amounts not exceeding the absorption capacity into the diet of each malabsorber who had improved with LFD caused relapse in none of the 14 subjects monitored for 2-6 months. In conclusion, LM seems an important cause of symptoms in Italian children with RAP. Assessment of the lactose absorption threshold of each subject of LBHTs provides a basis for reintroduction of "calibrated" amounts of lactose-containing foods (e.g., milk) into the diet.

Administration, Oral↗

Lactose malabsorption in children with symptomatic Giardia lamblia infection: feasibility of yogurt supplementation.

An investigation was carried out on 61 children suffering from symptomatic giardiasis with the object of verifying the incidence and entity of lactose malabsorption. Furthermore, the possibility of a substitutive yogurt diet was verified in the lactose malabsorbers. The subjects, all children older than 1 year, were studied according to a schedule that included a lactose hydrogen breath test (BT) performed prior to therapy and a further BT 60 days following therapy. The subjects were divided in two groups: group A, 40 children, received a dose of 250 ml of cow's milk; group B, 21 children, received a stress dose of 2 g/kg lactose (max 50 g). Those subjects who were lactose malabsorbers at the 60 day follow-up were also given a BT at 75 days, and in the case of persistent malabsorption, a further BT was performed after 24 h with the administration of yogurt (450 g containing 12.1 g of lactose). Furthermore, 40 subjects matched for age and sex but without any GI complaints served as controls. The results showed lactose malabsorption to be frequent in children with Giardia lamblia symptomatic infection. According to the BT with a standard lactose load, all patients were malabsorbers; when testing lactose absorption with 250 ml of cow's milk, 45% of patients were found to be malabsorbers. In the latter subjects, the oral load of yogurt was uniformly well tolerated and gave rise to no H2 increment on the BT. We conclude that the occurrence of lactose malabsorption of nutritional relevance is common in children suffering or having suffered from giardiasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Prospective study of lactose absorption during cancer chemotherapy: feasibility of a yogurt-supplemented diet in lactose malabsorbers.

Chemotherapy is a recognized cause of morphological alterations to the proximal intestine. Lactose malabsorption, the functional consequence of a small intestinal enzymatic derangement, has been shown to play an important role in causing gastrointestinal symptoms in subjects receiving chemotherapy. To establish a rational basis for the exclusion of lactose from the diet and to reduce the risk of developing gastrointestinal symptoms, we conducted a study of lactose absorption in 20 children during cancer chemotherapy. Because lactose is an important nutritional sugar, the tolerance of lactose provided by yogurt was examined. Lactose absorption was investigated by a hydrogen breath test (BT) after oral ingestion of milk (250 ml) containing physiological doses of lactose (12 g). The effect of yogurt supplementation was also tested by BT after meals of yogurt (450 g) also containing physiological doses of lactose (12.1 g). In 11 children, lactose malabsorption was detected by BT during the study before any gastrointestinal symptom revealed this status. Of these 11 children, no gastrointestinal discomfort developed in five receiving a lactose-excluded diet. In contrast, in the six children not restricted in lactose intake, gastrointestinal symptoms were observed 4 to 13 weeks after lactose malabsorption was detected by BT. The findings of our study suggested the usefulness of dietary supplementation with yogurt, a lactose-containing food, in children who developed lactose malabsorption. In fact, all lactose-malabsorbent children showed good lactose absorption and tolerance when tested by yogurt BT.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Lactose maldigestion in breast-feeding Gambian infants.

BACKGROUND: The ability of breast-feeding infants to utilize lactose, the major carbohydrate in breast-milk, is dependent on the presence of the enzyme lactase (E.C.3.2.1.108). Lactase is located in the brush border of the small intestine and because of its exposed position it is extremely vulnerable to pathogenic damage. Breast-fed Gambian infants have poor growth associated with intestinal damage beyond 3-4 months. The aim of this study was to assess the ability of Gambian infants aged 2-15 months (N = 113) to digest lactose and to see how this varied with age, intestinal permeability, and growth performance. METHODS: Lactose maldigestion was estimated by monthly measurements of urinary lactose and lactulose following an oral dose of the latter. RESULTS: Both urinary lactose excretion and lactulose maldigestion increased with age (p < 0.0001 ANOVA). Up to 6 months the mean urinary lactose: lactulose excretion ratio was within the quoted normal range (< 0.4). Beyond this age, mean values were hypolactasic. Lactose maldigestion was related to poor growth in both weight and length (r = -0.04, p < 0.0001, after age correction). Although a major part of this relationship was a reflection of the previously reported correlation between intestinal permeability and growth, more than 30% of the association was in addition to the permeability effect. Possible explanations are discussed. CONCLUSIONS: Moderate-to-severe hypolactasia does occur in breast-fed Gambian infants and is related to poorer-than-expected growth. However, this does not mean that breast milk intake should be reduced as the nutritional and immunological benefits of breast milk continue to outweigh any disadvantages.

Aging↗

Prevalence of lactose malabsorption in Galicia.

BACKGROUND: The aim of the current study was to evaluate the prevalence of lactose malabsorption (LM) in Galicia (NW Spain) in order to design nutritional intervention and/or public education strategies for high risk groups. METHODS: We conducted a study of LM by breath-hydrogen carbohydrate absorption test (BH2 test) in 850 healthy subjects. All subjects underwent BH2 tests following ingestion of a aqueous solution of 2 g lactose/kg body weight up to a maximum of 50 g. Subjects with LM were retested after ingesting 250 ml of milk and/or 250 ml of yogurt. RESULTS: The frequency of LM in the subjects who ingested 2 g lactose/kg body weight was 32.5%. This percentage decreased significantly with a decrease in the quantity of administered lactose and the vehicle was milk or yogurt-only 13.7% was LM after 250 ml of milk and 3.8% after 250 ml of yogurt. Gastrointestinal symptoms also depend on dosage of lactose and vehicle, decreasing from 54.3% after 2 g lactose/kg to 18.5% after milk and to 0% after yogurt. The frequency and number of gastrointestinal symptoms were significantly higher (p < 0.001) in LM than in lactose absorption (LA). CONCLUSIONS: Lactose malabsorption is prevalent in the population of Galicia. An important number of subjects identified as LM with usual clinical testing become LA when the ingestion of dairy products is limited so that the amount of lactose consumed is similar to that contained in a usual serving. Our results suggest the importance of BH2 testing following ingestion of usual consumed amounts of lactose per serving.

Adolescent↗

Disaccharidase activities in children: normal values and comparison based on symptoms and histologic changes.

BACKGROUND: The relationship between symptoms, intestinal mucosal histology, and disaccharidase activities is not well defined. An analysis of disaccharidase activities was performed in children grouped by age, symptoms, and intestinal mucosal histology and normal values established. METHODS: Disaccharidase activities and histology of 246 endoscopically obtained duodenal biopsies in 232 patients (121 girls; age range, 0.08-17 years; mean, 5.9 years) in a 3-year period were reviewed. Patients were divided into two groups based on absence (group 1; n = 142) or presence (group 2; n = 90) of diarrhea and were subdivided by age into, less than 24 months of age and 24 months of age or more. Histologic changes within groups were classified as (A) normal, (B) mild, or (C) moderate to severe based on villus height abnormalities. A questionnaire was sent to 34 patients with hypolactasia to assess the efficacy of lactose avoidance and/or lactase supplementation. RESULTS: All group 1 patients had normal findings in analysis of mucosal specimens, and their disaccharidase activities showed normal values because they had no diarrhea. The geometric means (95% confidence interval) in children aged less than 24 months are (in micromoles of substrate hydrolyzed per minute at 37 degrees C per gram protein) (units [U]) lactase, 36.7 (13.4-100.4); maltase, 178.5 (88.9-356.3); palatinase, 12.7 (3.8-41.5); and sucrase 60.0 (24.0-148.1). In children 24 months of age or more, the values are 23.2 (3.9-108.1), 167.6 (78.8-355.9), 12.7 (4.9-32.9), and 51.0 (20.5-126.0), respectively. Only lactase activity decreased with age (p < 0.05). No differences in disaccharidase activities were noted in patients with and without diarrhea if the mucosal histology was normal (group 1A vs. 2A). In patients with diarrhea, values were commensurate with the degree of mucosal injury, especially in the older group. Twenty-two of 27 patients (81%) who responded to the questionnaire had benefited from lactase supplementation and/or lactose avoidance. CONCLUSIONS: We have established normal values for disaccharidase activities in the pediatric population. Although the disaccharidase activities correlate more with degree of intestinal mucosal injury than with symptoms, their activities are difficult to predict accurately based on these criteria. If required, disaccharidase activities should be measured biochemically.

Adolescent↗

Ineffectiveness of breath methane excretion as a diagnostic test for lactose malabsorption.

BACKGROUND: In clinical and field conditions, breath gas analysis has been widely used in evaluating carbohydrate digestion. A field study was performed to determine the prevalence of lactose malabsorption in Myanmar children and to evaluate the possibility of using breath methane excretion to indicate lactose malabsorption in a field situation. METHODS: The study population consisted of 118 children aged 1 to 12 years. A hydrogen breath test after a lactose meal (2 g/kg, maximum 50 g) was used as a standard test. RESULTS: Lactose malabsorption was detected in 16.7% of children aged 1 to 2.9 years, with the prevalence increasing with age from 40.5% of those aged 3 to 5.9 years to 88.5% of those aged 6 to 8.9 years and reaching 91.7% in those aged 9 to 11.9 years. Lactose malabsorption was more prevalent when children were weaned before 4 months of age (87.2 vs. 41.1%; p < 0.01). Compared with lactose-tolerant children, those with lactose malabsorption had significantly higher concentrations of breath hydrogen excretion 60 minutes after the lactose test meal. Breath methane excretion was also significantly higher in samples at 120 minutes in children with lactose malabsorption. Breath methane excretion of greater than or equal to 2 parts per million at 180 minutes as a diagnostic test for lactose malabsorption had a sensitivity of 61.5% and a specificity of 84.6%. CONCLUSION: The breath methane test for lactose malabsorption has a lower sensitivity and specificity than the breath hydrogen test and therefore does not replace the lactose breath hydrogen test.

Breath Tests↗