(1/54) Ibuprofen augments gastrointestinal symptoms in lactose maldigesters during a lactose tolerance test.

BACKGROUND: Clinical symptoms during lactose tolerance test mimic those seen after therapeutic administration of prostaglandins, and resemble inflammatory processes. AIM: To investigate the possibility that lactose-induced gastrointestinal symptoms are associated with prostaglandins and/or nitric oxide. METHODS: After an overnight fast, nine maldigesters ingested lactose or sucrose with or without an inhibitor of prostaglandin synthesis (ibuprofen), in a randomised double-blind crossover trial. Gastrointestinal symptoms, concentrations of PGE2-M in blood and urine, and urinary 6-keto PGF1alpha (as indicators of prostaglandin synthesis), and urinary nitrate and nitrite as well as cyclic GMP excretions (as indicators of nitric oxide formation), were measured. RESULTS: Ibuprofen increased the first 3-h symptom scores (flatulence + borborygmi + abdominal bloating + pain) caused by lactose (P=0.008) but not sucrose. The concentrations of PGE2-M in the plasma and in the urine were unaffected. Lactose increased the urinary excretion of 6-keto PGF1alpha by about 30% (P=0.17), which was inhibited by ibuprofen (P=0.02). The production of nitric oxide was unaffected by lactose or ibuprofen. CONCLUSION: The inhibition of prostaglandin synthesis intensified gastrointestinal symptoms in lactose maldigesters, suggesting a negligible role for prostanoids in lactose-induced symptoms.  (+info)

(2/54) Effect of an episode of severe malnutrition and age on lactose absorption by recovered infants and children.

The degree of which the ability to absorb lactose can be regained after recovery from an acute episode of severe malnutrition is in doubt. Lactase activity was indirectly assessed by means of a standard lactose tolerance test (2 g lactose per kilogram of body weight) in 71 Peruvian Mestizo infants and children (age 5 to 55 months) who had suffered such an episode. All were studied just before discharge after several months of hospital rehabilitation, during which linear growth and weight gain had accelerated and signs of significant malabsorption of other nutrients had disappeared. Only 39% of the total group had a positive test (delta blood glucose greater than 25 mg/dl); there was a decreasing proportion of positive responders with increasing age. No difference in response attributable to type or severity of malnutrition was found. Comparison of the present data with previous data from children in the same community who had never been acutely malnourished suggests that acute malnutrition may hasten the permanent decline of lactase activity normally expected later in life.  (+info)

(3/54) Lactose intolerance among Mexican Americans.

Thirty-three Mexican Americans between the ages of 9 and 60 were interviewed and tested for lactose intolerance. The participants of the study included 16 children and 17 persons not related by birth, including the parents of the children. Determination of lactose intolerance was based on a rise of less than 25mg/100 ml of blood glucose as measured by an Ames Dextrostix/Reflectance Meter following consumption of a lactose load. Forty-seven percent of the 17 nonrelated Mexican Americans were lactose intolerant. There was a marked relationship between low rise in blood glucose and symptoms of diarrhea, flatulence, and distention. Sixteen children from four families had an incidence of 50 per cent intolerance. The findings of intolerance in two successive generations of three families and in both sexes of the families adds support to the contention that lactose intolerance has a genetic basis, without sex predilection.  (+info)

(4/54) Rapid and portable methods of lactose tolerance test administration.

Abbreviated, portable methods of lactose tolerance test administration were investigated. Results obtained with the Ames Reflectance Meter/Dextrostix system for blood glucose determination during lactose tolerance testing were compared with those obtained from a standard method, the AutoAnalyzer. Subjects who had maximum blood glucose rises below 20 mg/100 ml were considered to have a flat lactose tolerance curve and were designated lactose nondigesters. Results of the two methods were very similar for determination of maximum rise in blood sugar over fasting level, for obtaining values of individual blood sugar determinations, and for diagnosis of lactose nondigesters. The effect of omission of the final blood sample on tolerance test results was examined. It was found that maximum rises in blood glucose occurred before the final sample in 31 of 35 cases on the AutoAnalyzer and in 26 of 27 cases on the Reflectance Meter. In no case did omission of the final sample change the results of the lactose tolerance test.  (+info)

(5/54) Correlation of lactase activity, lactose tolerance and milk consumption in different age groups.

Small intestinal lactase activity in the health adult is either the same as in early infancy or may drop to very low levels. The behavior of the enzymatic state varies with the ethnic group studied. In those adults with low lactase activity little information is availalbe as to the age at which the lactase decreases. We attempted to determine a) the frequency of low intestinal lactase activity and b) the age at which the change occurs. For this purpose we reviewed in a large number of intestinal biopsies both histologically as well as for disaccharidase activities. The biopsies were obtained from a heterogeneous group of Caucasians, including patients, their siblings and parents. The patients were those with failure to thrive in whom no organic cause could be elicited, and those with the irritable colon syndrome. Patients ranged in age from 6 weeks to 50 years and out of a total of 1, 077 jejunal biopsies, 172 morphologically normal biopsies were selected. The milk drinking habits of 118 subjects and their families were elicited and 31 oral lactose tolerance tests performed. The mucosal lactase activity and sucrase-to-lactase ratio in those 172 individuals were plotted against age. In the first 3 years the mean lactase activity was 32.1 plus or minus 10.1 mumoles/g protein per min and the sucrase-to-lactase ratio was 1.7 plus or minus 0.5 with no change from year to year. However, after age 5 two separate groups emerge. A small group (24.6% of the population) with low lactase activity, and a second group possessing the same mean value for lactase activity as noted in the first 3 years. The low lactase activity group included children and adults with clinical lactose intolerance. These individuals consumed relatively small amounts of milk and when 12 of them were tested with an oral lactose tolerance test the result was a "flat" curve with a maximum rise in blood glucose of 9 plus or minus 3.2 mg/100 ml. The second group consumed more milk averaging 1 quart/day with no discomfort and when 19 were tested with oral lactose tolerance tests the values were normal. This study indicates that low lactase activity in the Caucasian population may make its appearance at the age of 5 years.  (+info)

(6/54) Relationship of milk consumption to blood glucose rise in lactose intolerant individuals.

Lactose intolerant populations are heterogeneous with respect to their milk-drinking habits. A gradation of lactase activity in the intolerant population may result in sufficient lactose hydrolysis to obviate symptoms and lead to continued milk consumption. This paper reports on differences in maximum blood sugar rise in lactose intolerant children who are observed to consume or reject milk. Of the 89 black elementary school children, 48 (54 per cent) evidenced a flat lactose tolerance curve. Twenty-eight of these 48 children (58 per cent) were defined as nonmilk drinkers. The maximum blood sugar rise was 12.3 mg/100 in the 20 lactose malabsorbers who were defined as milk drinkers. It appears that some lactose malabsorbing children may have sufficient, albeit lower, levels of lactase to hydrolyze moderate amounts of milk.  (+info)

(7/54) Lactose hydrolyzed milk.

Lactose intolerance is being reported in many populations. Yet, milk is highly nutritious and methods are being explored to use milk while limiting the lactose content. Thirty-two blacks 13-19 years of age were studied to determine a blood sugar rise with 8 ounces of the following test milks: 1) untreated whole milk (12 g/lactose); 2) 90% lactose hydrolyzed milk (1.2 g/lactose); and 3) 50% lactose hydrolyzed milk (6 g/lactose). In the 22 lactose malabsorbers, the peak blood sugars were: 1) untreated whole milk--4.4 mg/100 ml, 2) 90% lactose hydrolyzed milk--14.5 mg/100 ml, and 3) 50% lactose hydrolyzed milk--8.8 mg/100 ml. The 10 blacks with normal lactose absorption had a comparably high peak blood sugar on all three test milks. Differences between the blood sugar in the lactose absorbing and malabsorbing subjects when drinking untreated whole milk are significant (P less than 0.001); so are differences in the lactose malabsorbing subjects consuming untreated whole milk and 90% lactose hydrolyzed milk (P less than 0.001) as well as 50 and 90% lactose hydrolyzed milk. Symptoms were reported by three lactose malabsorbing subjects with untreated whole milk with two of the three symptomatic with 90% lactose hydrolyzed milk and none with 50% lactose hydrolyzed milk. No symptoms were reported by the lactose absorbers. Significant improvement in absorption with 90% lactose hydrolyzed milk is seen in low lactase subjects. Lactose hydrolyzed milk may serve as an important alternative for food planners wanting to provide milk to high risk populations with low lactase levels.  (+info)

(8/54) The prevalence of lactase deficiency and lactose intolerance in Chinese children of different ages.

OBJECTIVE: To determine lactose metabolism and lactase activity in Chinese children of different ages, prevalence of lactase deficiency (LD), and lactose intolerance (LI). METHODS: All 1168 healthy subjects between 3 and 13 years were recruited from schools in four large cities in China. They were screened by a 25 g lactose tolerance test. Some subjects were challenged with 50 g milk powder on different days. Both indicators, the expiratory H2 concentration and intolerance symptoms, were analyzed. RESULTS: LD occurred in 38.5% of children in the 3-5 year age group, and 87% of the 7-8 year and 11-13 year old groups. The age of occurrence for LD may be at 7-8 years among Chinese children. The prevalence of LI among Chinese children was 12.2% at age 3-5 years, 33.1% at age 7-8 years, and 30.5% at age 11-13 years, respectively. CONCLUSION: The results demonstrate that LD is very common in Chinese children from these four cities. LD and LI have a dose dependent response: lactose absorption and symptoms are based on lactase activity. The relationship between breast feeding history (or the history of cow milk intake) and lactase activity among Chinese children has not been established.  (+info)