Correlation between symptoms of the irritable bowel syndrome and the response to the food extract skin prick test

IRRITABLE BOWEL SYNDROME, FOOD INTOLERANCE AND NON- CELIAC GLUTEN SENSITIVITY. A NEW CLINICAL CHALLENGE

Approximately 80% of irritable bowel syndrome (IBS) patients report that their symptoms are triggered after ingesting one or specific food groups. Gluten, wheat and related proteins (e.g., amylase-trypsin inhibitors, and fermentable oligo-di-mono-saccharides and polyols (FODMAPs) are the most relevant IBS symptom triggers, although the true 'culprit(s)' is/are still not well established. The concept of causal relationship between gluten intake and the occurrence of symptoms in the absence of celiac disease and wheat allergy was termed non-celiac gluten sensitivity (NCGS). The borderline between celiac disease, wheat allergy, IBS and NCGS is not always clearly distinguishable, and the frequency and clinical identity of NGCS are still unclear. An overlap between IBS and NCGS has been detected. The incomplete knowledge of the etiopathogenesis of these clinical conditions, lack of data on their real epidemiology, as well as the absence of a gold standard for their diagnosis, make the overall picture difficult to understand "It is crucial to well define the interaction between IBS, food intolerance and NGCS, since the role of diet in IBS and its dietary management is an essential tool in the treatment of a large number of these patients". The objective of the present review is to provide an overview highlighting the interaction between IBS, food intolerance and NCGS in order to unravel whether gluten/wheat/FODMAP sensitivity represents 'facts' and not 'fiction' in IBS symptoms.

Food allergy in irritable bowel syndrome: The case of non-celiac wheat sensitivity

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders, having a prevalence of 12%-30% in the general population. Most patients with IBS attribute their symptoms to adverse food reactions. We review the role of diet in the pathogenesis of IBS and the importance of dietary factors in the management of these patients. The MEDLINE electronic database (1966 to Jan 2015) was searched using the following keywords: "food", "diet", "food allergy", "food hypersensitivity", "food intolerance", "IBS", "epidemiology", "pathogenesis", "pathophysiology", "diagnosis", "treatment". We found 153 eligible papers; 80 were excluded because: not written in English, exclusive biochemical and experimental research, case reports, reviews, and research otherwise not relevant to our specific interest. We selected 73 papers: 43 original papers, 26 reviews and 4 letters to the editor. These papers focused on IBS pathogenesis, the association between IBS and atopy, and between IBS and food allergy, the relationship between IBS and non-celiac wheat sensitivity, the role of diet in IBS. Pending further scientific evidence, a cautious approach is advisable but the concept of food allergy should be included as a possible cause of IBS, and a dietary approach may have a place in the routine clinical management of IBS.

Epidemiology of food allergy in Latin America

Food allergy is growing worldwide at an alarming rate. A group of eight foods account for over 90% of the reactions in Europe and the United States. However, little is known about the frequency of sensitization to these foods in Latin American, and if other native foods from this region are an important source of sensitization. The objective of this review was to analyse the epidemiological studies in Latin America about food allergy and to compare them with the studies in the United States and Europe.

Indication of immune activation in patients with perceived food hypersensitivity

Majority of the patients with perceived food hypersensitivity have irritable bowel syndrome (IBS), and a significant proportion of IBS patients also attribute their gastrointestinal complaints to food items. Different factors such as disturbed intestinal fermentation, enteric dysmotility, post-infectious changes and altered microbial flora in the colon as well as psychological disturbances likely play a role in the pathophysiology and symptoms generation in patients with food hypersensitivity. In addition, a number of studies in these patient groups indicate that local, systemic and mucosal immune systems are activated. The question now is no longer intestinal immune activation, but how the immune system is activated in these patients. In the following review, the potential pathogenetic role of the immune system and evidence of immune activation are reported in patients with perceived food hypersensitivity.

Diet and functional abdominal pain in children and adolescents

Functional abdominal pain (FAP) is a common complaint among children and adolescents. For many patients, symptoms exacerbate with eating. This review discusses findings concerning the role of diet in FAP. The foods that are discussed are divided into 2 major groups: food allergies or intolerances, which focus on milk, gluten, and fermentable oligosaccharides, disaccharides, monosaccharides, and polyols; and functional foods, which hone in on foods that reduce abdominal pain in adolescents such as fiber, peppermint oil, and probiotics. Lastly, we discuss the role of eating habits in FAP and how the physiology of eating may be the real culprit of symptoms associated with eating.

Discrepancies between the responses to skin prick test to food and respiratory antigens in two subtypes of patients with irritable bowel syndrome

AIM

To compare the response to skin prick tests (SPTs) to food antigens (FAs) and inhalant allergens (IAs) in patients with two subtypes of irritable bowel syndrome (IBS) and healthy controls.

METHODS

We compared the results of SPTs for IAs and FAs in 87 volunteers divided into three groups: diarrhea predominant IBS (D-IBS) Group I (n = 19), constipation predominant IBS (C-IBS) Group II (n = 17), and normal controls Group III (n = 51).

RESULTS

Of the 285 tests (171 for FAs and 114 for IAs) performed in Group I we obtained 45 (26.3%) positive responses for FA and 23 (20.1%) for IA. Of the 153 tests for FA in Group II, we obtained 66 (20.1%) positive responses, and of the 102 tests for IA, we obtained 20 (19.6%) positive responses. Of the 459 tests for FA performed in Group III, we obtained 39 (84%) positive responses, and of the 306 for IA, we obtained 52 (16.9%) positive responses. The numbers of positive responses were not significantly different between the three groups, but in the D-IBS group, the number of SPT FA responses differed significantly from those for the other two groups (P > 0.01).

CONCLUSION

Despite the small number of cases studied, the higher reactivity to FAs in Group I compared to Groups II and III adds new information, and suggests the presence of a possible alteration in intestinal epithelial function.

Alterations of food antigen-specific serum immunoglobulins G and E antibodies in patients with irritable bowel syndrome and functional dyspepsia

BACKGROUND

Post-prandial worsening of symptoms as well as adverse reactions to one or more foods are common in the patients with functional gastrointestinal diseases, such as irritable bowel syndrome (IBS) and functional dyspepsia (FD). However, the role played by true food allergy in the pathogenesis of these diseases is still controversial and there are no well-established tests to identify food allergy in this condition.

OBJECTIVE

To investigate serum food antigen-specific IgG, IgE antibody and total IgE antibody titres in controls and patients with IBS and FD, and to correlate symptoms with the food antigen-specific IgG titres in IBS and FD patients.

METHODS

Thirty-seven IBS patients, 28 FD patients and 20 healthy controls participated in this study. Serum IgG and IgE antibody titres to 14 common foods including beef, chicken, codfish, corn, crab, eggs, mushroom, milk, pork, rice, shrimp, soybean, tomatoes and wheat were analysed by ELISA. Serum total IgE titres were also measured. Last, symptomatology was assessed in the study. Results IBS patients had significantly higher titres of IgG antibody to crab (P=0.000), egg (P=0.000), shrimp (P=0.000), soybean (P=0.017) and wheat (P=0.004) than controls. FD patients had significantly higher titres of IgG antibody to egg (P=0.000) and soybean (P=0.017) than controls. The percentage of individuals with detectable positive food antigen-specific IgE antibodies of the three groups did not show any significant differences (P=0.971). There were no significant differences between IBS patients, FD patients and controls in the serum total IgE antibody titres (P=0.978). Lastly, no significant correlation was seen between symptom severity and serum food antigen-specific IgG antibody titres both in IBS and FD patients.

CONCLUSION

Serum IgG antibody titres to some common foods increased in IBS and FD patients compared to controls. But there is no significant correlation between symptom severity and elevated serum food antigen-specific IgG antibodies in these patients.

Relationship between asthma and irritable bowel syndrome: role of food allergy

The increasing prevalence of both asthma and irritable bowel syndrome (IBS) are major health problems. One hundred twenty-five patients with asthma and 95 healthy subjects were included in this study. The rate of IBS was 29.6% and 12.7% (p < 0.005), and the incidence of food allergy was 7.2% and 2.1% (p > 0.05) respectively for asthma and control group. There was no significant association between asthma related parameters, IBS, and food allergy. There is not a single clear reason as to what causes IBS, so further studies are needed to clarify the potential pathogenic mechanisms underlying the association between IBS and asthma.

Food intolerance and skin prick test in treated and untreated irritable bowel syndrome

AIM: To correlate the clinical features of treated and untreated patients with irritable bowel syndrome (IBS) to the results of skin prick test (SPT) for food and inhalant allergens.

METHODS: We recruited 105 subjects to form three different target groups: treated group (n = 44) undergoing treatment for IBS, untreated group (n = 31) meeting the Rome II criteria without treatment for IBS, control group (n = 30) with no IBS symptoms.

RESULTS: SPT results were different among the three groups in which SPT was positive in 17 (38.6%) treated patients, in 5 (16.1%) untreated patients and in 1 (3.3%) control (P < 0.01). The number of positive SPTs was greater in the IBS group than in the control group (P < 0.001). The number of positive food SPTs was higher in the treated IBS group than in the untreated IBS group (P = 0.03).

CONCLUSION: Positive food SPT is higher in IBS patients than in controls.

Irritable bowel syndrome in young and elderly patients with stable asthma

BACKGROUND

It has been speculated that asthma and irritable bowel syndrome may share common pathophysiological processes.

AIM

To estimate the prevalence of irritable bowel syndrome in young and elderly patients with stable asthma.

PATIENTS AND METHODS

Sixty-five young (age < 60 years) and 66 elderly (age > or = 60 years) stable asthmatics, and 119 age-matched healthy volunteers were enrolled. In all participants, presence of irritable bowel syndrome, quality of life and psychological status were evaluated.

RESULTS

The prevalence of irritable bowel syndrome in asthmatic group was higher than that in the control group (27.5% versus 16.8%; odds ratio, 1.8 [1.0-3.4]; p=0.04). The prevalence of irritable bowel syndrome was significantly higher in young asthmatics than in age-matched healthy controls (36.9% versus 20.3%; odds ratio, 2.2 [1.0-5.1]; p=0.04) and than in elderly asthmatics (36.9% versus 18.2%; odds ratio, 0.3 [0.1-0.8]; p=0.01). Logistic regression analysis identified the younger age (odds ratio, 2.1 [1.1-3.8]; p=0.01), and the presence of asthma (odds ratio, 1.9 [1.0-3.5]; p=0.03) as independent risk factors for irritable bowel syndrome in all participants after adjusting for gender. We also found impaired quality of life to be associated with the presence of irritable bowel syndrome and asthma in all participants after adjusting for age and gender.

CONCLUSION

The prevalence of irritable bowel syndrome appears to be significantly higher in young asthmatics, but not in elderly asthmatics, compared to age-matched healthy counterparts. Potential pathogenic mechanisms of higher irritable bowel syndrome prevalence in young asthmatics need to be explained by further studies.