Xylose

Aim of the investigators' study is to evaluate one of the symptoms described by patients affected with the so-called "not-celiac wheat sensitivity" (NCWS). NCWS patients may be defined as ones, neither celiac or allergic to wheat, who develop symptoms following wheat consumption and improve on Gluten Free Diet (GFD). Among these, patients often report the appearance of bloating and abdominal pain, and, sometimes, swelling of fingers and face, shortly after ingestion of wheat. They also refer that swelling tends to last for some hours and then to disappear on GFD. To our knowledge, this disorder has never been investigated neither proved.
For the investigators' research, the investigators selected adult patients, both genders, affected with NCWS. Diagnostic criteria include: 1) symptoms disappearance on GFD, 2) testing negative for celiac disease [anti-tTG and EMA, and with biopsy Marsh 0-1] and wheat allergy [serum specific IgE for wheat], 3) positive response to a double-blind placebo-controlled challenge (DBPC) with wheat or placebo.
Patients will be recruited among subjects referring, as outpatients, to the Department of Internal Medicine, 'Giovanni Paolo II' Hospital of Sciacca (Agrigento), and of Internal Medicine of the University of Palermo, from January 2012 to October 2013. The investigators will include patients referring for functional dyspepsia and/or irritable bowel syndrome (IBS)-like symptoms. All recruited patients must report body's swelling immediately after wheat ingestion. In all recruited patients, NCWS diagnosis was posed during the previous years, according to the above mentioned criteria.
Patients, all on GFD for at least 30 days, will undergo to another DBPC with wheat or placebo (xylose), performed by administering capsules coded as A or B containing wheat or xylose, respectively. Capsules A or B will be administered once, and then, after 1 week of washout, patients received the other capsules, given once too. Before and 2 hours after every challenge, patients will undergo a complete medical examination (measurement of body weight, height, body mass index [BMI], waist circumference, diameter of thighs, legs, arms, and fingers), and we will perform bioelectrical impedance analysis and collect blood sampling, for identification of possible markers (bioelectrical, immunologic, hormonal, etc) that may help to demonstrate and explain mechanisms of examined symptom.