View clinical trials related to Lactose Intolerance.
Filter by:Most people are born with the ability to digest lactose, a dissacharide consisting of β-D-glucose and β-D-galactose, because of the presence of lactase at the brush border of the small intestine. In about 75% of the world population the activity of this enzyme decreases after weaning (primary hypolactasia or lactase-nonpersistence), resulting in incomplete digestion of lactose and lactose malabsorption in adulthood (1). Secondary forms of lactose malabsorption may be due to inflammation or functional loss of the intestinal mucosa such as celiac disease, infectious enteritis or Crohn's disease. Very rarely, lactase deficiency is congenital due to an autosomal recessive genetic disorder, preventing lactase expression from birth (2). Whereas some people with lactose malabsorption are asymptomatic, most lactose-nonpersisters experience symptoms like abdominal pain, bloating, excess flatulence or diarrhea. Lactose intolerance refers to the syndrome of having one or more symptoms after consumption of lactose-containing food (3). At present, the origin of the symptoms of lactose-intolerance is not well understood. Several studies have indicated a poor correlation between lactose maldigestion and symptoms of lactose intolerance (4). In a study by Vonk et al. (2003), lactose intolerant subjects with severe symptoms (diarrhea) and intolerant subjects with only mild symptoms (without diarrhea) did not differ in degree of lactose digestion in the small intestine indicating a similar lactase activity and leading them to the hypothesis of a "colon resistence factor" (5). It was suggested that the colonic processing of maldigested lactose may play a role in the symptoms experienced by lactose intolerant patients. When lactose is malabsorbed and enters the colon, it is rapidly fermented by the resident microbiota into a variety of metabolites including lactate, formate, succinate and short chain fatty acids (SCFA, acetate, propionate, butyrate) as well as gases (H2, CO2 and CH4). When incubating fecal samples from lactose-tolerant and intolerant subjects with lactose, the samples from the lactose-intolerant subjects showed faster production rates of D- and L-lactate, acetate, propionate and butyrate, as compared to tolerant subjects (6). Although the colon is thought to possess a high capacity to absorb SCFA, it was hypothesized that a temporary accumulation of these metabolites due to rapid fermentation of maldigested lactose could be responsible for abdominal pain, excess flatulence and bloating (7;8). Possible mechanisms proposed to explain how SCFA might induce symptoms included an increase in the osmotic load that draws fluid to the colonic lumen, changes in colonic motility and an increased colonic sensitivity (9-11). However, the calculated amount of fluid drawn in the colon is unlikely to cause symptoms considering the high water absorbing capacity of the colon and the effect of SCFA on colonic motility and colonic sensitivity have only been observed in rats and not in humans. More recently, Campbell et al. introduced the bacterial metabolic toxin hypothesis, stating that also other bacterial metabolites, such as alcohols, aldehydes, acids and ketones, resulting from carbohydrate fermentation play a role in the pathogenesis of lactose-intolerance. These metabolites might inhibit bacterial growth and affect eukaryotic cells (12). In our own previous studies in which we related colonic fermentation patterns to parameters of cytotoxicity, we identified compounds like propionic acid, medium chain fatty acids, 1-octanol and heptanal as more prevalent in the most cytotoxic samples (13), supporting the hypothesis of Campbell et al. Therefore, it seems necessary to include not only SCFA, but also other metabolites, in the investigation of the pathogenesis of lactose intolerance. Differences in fermentation patterns might be associated with differences in the composition and/or activity of the intestinal microbiota. Evidence on the potential role of the colonic microbiota in lactose intolerance is very limited. Total bacterial numbers were not significantly different between 16 intolerant and 11 tolerant lactose maldigesters although a negative correlation between total bacteria and symptom score was found (14). Similarly, the composition of fecal microbiota was not different between 5 intolerant and 7 tolerant subjects (6).
Background: The association of fructose and lactose intolerance and malabsorption with the symptoms of different functional gastrointestinal disorders (FGID) is unclear. The mechanisms behind the multi-organ symptoms remain unclear. Both FGID and saccharide intolerances are common (>10% of any given population). Dietary modification based on intolerance diagnostics could provide an effective treatment for FGID, which are otherwise difficult to treat. Aim: To investigate the prevalence and interrelationships of fructose and lactose intolerance (symptom induction) and malabsorption (breath test gas production) and their association with clinical GI as well as non-GI symptoms in FGID and the outcome of standard dietary intervention. Mechanisms related to symptom genesis will be investigated using metabolomic analysis of plasma and urine by gas chromatography/time-of-flight mass spectrometry (GC/TOFMS). Methods: Fructose and lactose intolerance (defined by positive symptom index) and malabsorption (defined by increased hydrogen/methane) will be determined in successive male and female FGID patients in a single center using breath-testing. Symptoms will be recorded using standardised questionnaires and the Rome III criteria. The prevalence of the intolerances in the different FGID subgroups and the associations between breath testing results, clinical symptoms and the outcome of dietary modification will be assessed. Factors predictive of the outcome of dietary modulation will be screened for. GC/TOFMS will be used to assess the human and microbial metabolome in urine and plasma.
The objective of this study is to determine the prevalence of secondary lactose intolerance in renal transplant recipients (RTR) with chronic norovirus infection. In the investigators cohort of 1000 renal transplant recipients (RTRs) in the University Hospital of Zurich, the investigators are currently aware of 10 patients with chronic norovirus infection, which was proven by positive polymerase chain reaction (PCR) analysis of recent stool samples, whereas chronic virus shedding is defined as more than two PCR positive samples in an interval of at least one month. Concomitant viral (other than norovirus), bacterial or parasitic (particularly Gardia lamblia) intestinal infections are excluded by negative stool cultures and PCR analyses, respectively. Main exclusion criterion for the present case series is a concomitant intestinal infection (other than norovirus) and primary lactose intolerance, which is previously excluded by absence of the CC genotype of the DNA variant -13910 T/C upstream in the LCT gene. After obtaining written and oral informed consent, the investigators perform a lactose hydrogen breath (LH2BT) test and a lactose tolerance test (LTT) in all eligible RTRs with proven chronic norovirus infection irrespective of current abdominal symptoms. The study population (N=10) is divided into two groups according to the gastrointestinal symptoms (asymptomatic versus symptomatic, such as chronic diarrhoea or diffuse abdominal discomfort). The investigators chose the cut-off three or more stools per day as indicative of diarrhoea for the purpose of this study. RTRs with otherwise unexplainable chronic diarrhoea but absent norovirus infection serve as control group (N=10).
The primary objective of this study is to demonstrate that ALTHERA® is equal or superior in efficacy than NUTRAMIGEN®
Lactose intolerance (LI), also known as lactose malabsorption is the most common type of carbohydrate malabsorption. It is associated with the inability to digest lactose into its constituents, glucose and galactose, due to low levels of lactase enzyme activity (1-2). At birth, lactase activity is at the highest and it declines after weaning (1-2). The unabsorbed lactose is metabolized by colonic bacteria to produce gas (hydrogen (H2) and methane (CH4)) and short chain fatty acids. Symptoms related to LI appear 30 minutes to 2 hours after consumption of food products containing lactose. Related symptoms include: bloating, cramping, flatulence and loose stool (1-2, 17-18). Highest rates of LI are found in the Asian populations, Native Americans and African Americans (60-100%), while lowest rates are found in people of northern European origin (including northern Americans) (3-4). The diagnosis of LI based on patients' symptoms is sometimes problematic, since these symptoms are not specific and may differ from one patient to another. Breath hydrogen test have been advocated as the best diagnostic tool for the assessment of LI (15-16). During the test, subjects are sampled for hydrogen levels of breath samples at base line and every 30 minutes after the administration of 50 grams of oral lactose, for a total period of 180 minutes. A breath sample with > 20 ppm above baseline is considered positive for LI (15-16). There are no established treatments for LI, other than almost complete avoidance of lactose rich dairy products. Avoidance of dairy products is a major concern since its outcome may result in a dietary calcium intake that is well below recommended dose of 1,000 mg per day for men and women and 1,300 mg for adolescents (8-10). For this reason different course of action needs to be considered instead of a complete exclusion of dairy products by LI patients. Two possible interventions in the case of LI are the supplement of commercially available lactase (tablets) or the addition of probiotics. The consumption of lactase enzyme as a food supplement may assist in restoring adequate levels of the enzyme needed for hydrolysis of lactose, especially for patients with low, or non existent levels of lactase. On the other hand, lactase products are problematic since not all lactase preparations are of the same concentration. Moreover, it is difficult to asses the amount of lactase tablets needed in order do fully hydrolyze lactose in each dairy mill (14). Probiotics are live microorganisms that are commonly used in order to prevent or treat a disease. The current definition by the Food and Drug Administration and the World Health Organization is "Live microorganisms which, when administered in adequate amounts, confer a health benefit on the host." These microorganisms are a heterogeneous group, they are nonpathogenic and produce beta- galactosidase or lactase intracellularly that may assist in the digestion of lactose (11). Studies have shown that people with lactose intolerance tolerated the lactose in yogurt better than the same amount of lactose in milk. The assumption was that the presence of lactase producing bacteria in the yogurt, especially Lactobacillus acidophilus, contributed to the digestion and absorption of lactose (5-6, 13). It was also found that the presence of Lactobacillus bulgaricus and Streptococcus thermophilus alleviate lactose intolerance through their ability to produce lactase enzyme (7). Finally, in another study it was found that consumption of milk containing Bifidobacterium longum resulted in significantly less hydrogen production and flatulence as compared to the consumption of control pasteurized milk (12). Based on the mentioned data, the investigators speculate that the administration of probiotics may assist with the consumption of dairy products containing lactose. Therefore, the aim of this study is to evaluate the effect of probiotics on patients with LI.
Fermented dairy products, especially real Yoghurt, are often tolerated better by lactose malabsorbers than unfermented dairy products. The intake of dietary supplements containing acid Lactase derived from Aspergillus oryzae with lactose containing foodstuffs is known to reduce/alleviate symptoms of lactose intolerance in lactose malabsorbers. The study aims to compare the effect of the intake of a combination of yoghurt bacteria and acid lactase to the effect of yogurt bacteria or acid lactase alone on the lactose digestion in lactose malabsorbers. It is hypothized that the combination preparation will be more effective and/or will show a more reliable effect than the two mono-preparations.
The goal of this study was to examine the effects of self-perceived lactose intolerance (SPLI) as it relates to calcium intake and specific health problems that have been attributed to reduced intake of calcium and foods from the dairy group in a nationally representative multi-ethnic sample of adults.
Lactose is a carbohydrate found in milk,and Lactase Deficiency (LD) is a condition in which the small intestine cannot digest this carbohydrate due to absent or insufficient amounts of lactase.Individuals with LD may be intolerant of lactose in the diet and experience abdominal cramps, bloating and diarrhea; however the response is variable.Some tolerate moderate amounts of lactose without adverse effect,whereas others experience severe symptoms in response to even small doses. These problems may be representative of wider issues regarding individual tolerance to diet containing ubiquitous poorly absorbed, fermentable carbohydrates (such as: fructose, fructans)and be relevant to symptom generated in patients with diarrhea predominant irritable bowel syndrome (D-IBS). This project will investigate the effects of diet,lifestyle stress and psychiatric dietary on the development of functional gastrointestinal symptoms. Lactose will be used to assess tolerance to dietary challenge, a test that is particularly relevant in a Chinese population with a high prevalence of lactase deficiency.
The primary objective is to determine the compared clinical efficacy of Lactase Eurofarma (test drug), showing non-inferiority to Lactaid® (comparative drug) in the supportive treatment of lactose intolerance and to assess the safety and tolerance of Lactase Eurofarma (test drug) in the supportive treatment of lactose intolerance.
The study primary objective is to compare the clinical efficacy of two formulations in the supportive treatment of lactose intolerance.