Lactose Intolerance: Common Misunderstandings

Lactose intolerance primarily refers to a syndrome having different symptoms upon the consumption of foods containing lactose. It is one of the most common form of food intolerance and occurs when lactase activity is reduced in the brush border of the small bowel mucosa. Individuals may be lactose intolerant to varying degrees, depending on the severity of these symptoms. When lactose is not digested, it can be fermented by gut microbiota leading to symptoms of lactose intolerance that include abdominal pain, bloating, flatulence, and diarrhea with a considerable intraindividual and interindividual variability in the severity of clinical manifestations. These gastrointestinal symptoms could be similar to cow's milk allergy and could be wrongly labeled as symptoms of "milk allergy." There are important differences between lactose intolerance and cow's milk allergy; therefore, a better knowledge of these differences could limit misunderstandings in the diagnostic approach and in the management of these conditions

Gut Microbiota as Potential Therapeutic Target for the Treatment of Cow’s Milk Allergy.

Cow's milk allergy (CMA) continues to be a growing health concern for infants living in Western countries. The long-term prognosis for the majority of affected infants is good, with about 80% naturally acquiring tolerance by the age of four years. However, recent studies suggest that the natural history of CMA is changing, with an increasing persistence until later ages. The pathogenesis of CMA, as well as oral tolerance, is complex and not completely known, although numerous studies implicate gut-associated immunity and enteric microflora, and it has been suggested that an altered composition of intestinal microflora results in an unbalanced local and systemic immune response to food allergens. In addition, there are qualitative and quantitative differences in the composition of gut microbiota between patients affected by CMA and healthy infants. These findings prompt the concept that specific beneficial bacteria from the human intestinal microflora, designated probiotics, could restore intestinal homeostasis and prevent or alleviate allergy, at least in part by interacting with the intestinal immune cells. The aim of this paper is to review what is currently known about the use of probiotics as dietary supplements in CMA

The role of the commensal microbiota in the regulation of tolerance to dietary allergens.

In this report we review the evidence that environmental stimuli that perturb naturally selected host-microbe interactions are driving the increasing prevalence of food allergy and examine the mechanisms by which commensal bacteria regulate tolerance to dietary allergens. Recent findings Antibiotic use and the consumption of a high fat/low fiber diet have a major, and rapid, impact on gut bacterial populations with long-term consequences for both overall microbial community structure and the regulation of host immunity. Recent work emphasizes the role of mucosa-associated commensal bacteria in eliciting a barrier protective response critical to preventing allergic sensitization to food. Murine model studies are informing the development of novel live biotherapeutic approaches as an adjunctive therapy to enhance antigen specific oral desensitization and promote lasting tolerance in patients with food allergy. Summary Strategies based on modulating the composition and/or functionality of the gut microbiome hold promise for the treatment of food allergy

Chronic diarrhoea in children.

Chronic diarrhoea in children shows an age related spectrum. In infants and young children a major role is related to persistent intestinal infections, intolerance to specific nutrients such as cow's milk protein, and toddler's diarrhoea. In older children and adolescents, inflammatory bowel diseases are strongly increasing and nonspecific diarrhoea is also frequent. Coeliac disease is a major cause of diarrhoea throughout childhood. In neonates, congenital diarrhoea is a rare but severe syndrome that includes several highly complex diseases. In children, diagnosis should be based on noninvasive techniques. Endoscopy should be decided based on clinical criteria, but also driven by noninvasive tests to assess the digestive absorptive functions and intestinal inflammation. A stepwise approach may reduce the need of endoscopy, also in the light of its relatively limited diagnostic yield compared to adult patients. Treatment of chronic diarrhoea in children is also substantially different from what is generally done in adults and includes a major role for nutritional interventions. Therefore chronic diarrhoea in children is a complex age-specific disorder that requires an age-specific management that is in many aspects distinct from that in adults