Testing wheat avoidance and wheat challenge in people with mild-to-moderate psoriasis

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults with mild-to-moderate psoriasis. It tests whether a wheat-free diet and then a wheat challenge change psoriasis symptoms.

Age

Over 18 and under 65 years (the record lists 18 Years to 65 Years).

Sex

All sexes can join.

Disease stage

Mild-to-moderate psoriasis. Severe chronic plaque-type psoriasis (based on BSA) is not allowed.

Earlier treatment

No systemic therapy for psoriasis for at least 3 months before joining. No treatment with steroids or immunological therapies.

Biomarker or test result

Negative blood tests for celiac disease (anti-DGP IgA and IgG, anti-tTG IgA and IgG, EmA). No wheat allergy (negative prick-test and/or specific IgE for wheat, gluten, gliadin).

Main reasons for not taking part

• Severe chronic plaque-type psoriasis
• Already avoiding gluten/wheat and refusing to eat it again before the study
• Pregnancy
• Chronic inflammatory bowel disease or other digestive system disease
• Cancer, or chemotherapy or radiotherapy

The registry criteria, word for word

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

• Are you between 18 and 65 years old?YesNo

What the trial wants to find out

Psoriasis is a systemic chronic inflammatory immune-mediated disease whose etiopathogenetic mechanisms involve genetic predisposition, and immunological and environmental factors. Its prevalence is about 3% in adults, and it is characterized by well-demarcated, erythematous plaques, covered by silvery-white scales, in elbows, knees, trunk, and scalp. However, psoriasis is far from being considered just a dermatologic condition because the cytokine's cascade, which lays behind its inflammatory and immune-mediated pathogenesis, can determine multiple systemic manifestations. In addition, several patients with psoriasis often complains of gastrointestinal (GI) symptoms. Therefore, authors focused their attention over the gut-skin axis and its possible pathogenetic and immunoregulatory role in psoriasis (i.e., altered gut barrier, increased blood concentration of gut microbiota-derived metabolites, systemic inflammation). In this context, several dietetic approaches (e.g., Mediterranean, low calories, protein-restricted, vegetarian diets, and gluten-free diet, GFD) have shown a certain efficacy in improve psoriasis cutaneous and systemic manifestations. In recent years, the existence of a wheat-related disorder in patients who do not suffer from CD or wheat allergy (WA) has been definitively ascertained and defined as Non-Celiac Wheat Sensitivity (NCWS). Its prevalence in the general population is unknown, but self-reported NCWS is around 10%. This condition is characterized by both GI and extraintestinal symptoms, which are triggered by wheat ingestion. In these patients, wheat ingestion might lead to alteration in intestinal permeability and gut microbiota and to systemic immune activation and inflammation. Based on the evidence of gut involvement in the pathogenesis and clinical manifestation of psoriasis, as well as on the ability of gluten/wheat to increase intestinal permeability, it could be hypothesized that gluten/wheat may represents one of the pathogenetic environmental factors of psoriasis and that its intake may be able to worsen symptoms in affected patients. The investigators hypothesize that a wheat-free diet (WFD) can reduce the inflammatory state and ameliorate the clinical symptoms in psoriasis patients. The successive clinical and immunologic reaction to the re-exposure to wheat ingestion, performed by an open challenge, will be also evaluated to confirm a wheat-dependent mechanism and to understand the underlining physiopathology.

The 2 groups in the trial

• Open wheat challenge groupExisting treatment, for comparison

  Before starting the elimination diet (time 0, T0), intervention patients will be evaluated by experienced dermatologists, as well as by physicians with expertise in the field of food intolerance about GI and extraintestinal symptoms related to foods intake. Moreover, all these subjects will be subjected to blood, urine, and stools collections, and to a dietary consult, and a food and symptom's diary will be provided to all patients, which must be filled-in daily. After 2 months of elimination diet (time 1, T1), intervention patients will be evaluated again both clinically and by laboratory techniques, identically to T0. At this time-point, intervention patients will go to an open challenge, with reintroduction of wheat. After 2 weeks of open diet or whenever dermatologic, intestinal and/or extraintestinal symptoms should return or intensify (T2int), patients will be valued again both clinically and by laboratory techniques, identically to T0 and T1, and then will end the study.

  Treatment: Open wheat challenge

• Placebo groupPlacebo, for comparison

  Before starting the elimination diet (time 0, T0), control patients will be evaluated by experienced dermatologists, as well as by physicians with expertise in food intolerance. Moreover, patients will be subjected to blood, urine, and stools collections, and to a dietary consult, and a food and symptom's diary will be provided. After 2 months of elimination diet (time 1, T1), patients will be evaluated, identically to T0. Then, control patients will be asked to repeat the elimination diet, this time removing wheat and all cow's milk products for further 2 months (T2con). Then, patients will be valued again both clinically and by laboratory techniques, identically to T0 and T1. Then, patients will go to an open challenge, with reintroduction of wheat. After 2 weeks of open diet or whenever dermatologic, intestinal and/or extraintestinal symptoms should return or intensify (T3con), patients will be valued again, identically to T0, T1 and T2con, and then will end the study.

  Treatment: Placebo challenge