Autoimmune Diseases and Serum Autoantibodies in NCWS and IBS Patients
Autoimmune Diseases and Serum Autoantibodies in NCWS and IBS Patients
In recent years, a new gluten- or wheat-related disease has emerged, a condition labelled
 "non-celiac gluten sensitivity" (NCGS) or "non-celiac wheat sensitivity" (NCWS). Given the
 lack of a diagnostic biomarker, NCGS/NCWS mostly remains a diagnosis of exclusion, especially
 respect to CD and WA, so a confirmatory test is required. The Salerno experts suggested the
 double-blind, placebo-controlled (DBPC), cross-over, gluten/wheat challenge as the gold
 standard test to discriminate true NCGS/NCWS patients. There are conflicting data about the
 real mechanisms which induce symptoms in NCGS/NCWS patients after wheat ingestion. Some
 Authors suggested a prevalent role for Fermentable
 Oligosaccharides-Disaccharides-Monosaccharides and Polyols (FODMAPs), rather than gluten in
 determining the symptoms. Other studies underlined the activation of mechanisms of both
 innate and acquired immunity in NCWS patients, after wheat ingestion. In the present study,
 we included a group of consecutive NCWS patients, diagnosed with DBPC wheat challenge, to
 evaluate a) the frequency of autoimmune diseases, b) the frequency and pattern of serum ANA
 and other non-organ-specific and/or organ-specific autoantibodies, and c) the possible
 correlations between autoimmune diseases and serum autoantibodies presence and other
 NCWS-related disease characteristics, in comparison with age- and sex- matched healthy blood
 donors and IBS patients unrelated to NCWS.
In recent years, a new gluten- or wheat-related disease has emerged, a condition labelled
 "non-celiac gluten sensitivity" (NCGS) or "non-celiac wheat sensitivity" (NCWS). This is very
 often a self-reported condition, since patients refer to intestinal (mainly irritable bowel
 syndrome (IBS)-like) and/or extra-intestinal symptoms (i.e. fatigue, headache) caused by
 gluten or wheat ingestion, even though they do not have celiac disease (CD) or wheat allergy
 (WA). Given the lack of a diagnostic biomarker, NCGS/NCWS mostly remains a diagnosis of
 exclusion, especially respect to CD and WA, so a confirmatory test is required. The Salerno
 experts suggested the double-blind, placebo-controlled (DBPC), cross-over, gluten/wheat
 challenge as the gold standard test to discriminate true NCGS/NCWS patients.

 However, there are conflicting data about the real mechanisms which induce symptoms in
 NCGS/NCWS patients after wheat ingestion. Some Authors suggested a prevalent role for
 Fermentable Oligosaccharides-Disaccharides-Monosaccharides and Polyols (FODMAPs), rather than
 gluten in determining the symptoms. Other studies underlined the activation of mechanisms of
 both innate and acquired immunity in NCWS patients, after wheat ingestion. In line with the
 evidence of an immunologic activation in NCWS, we showed in a previous study that about one
 quarter of NCWS patients suffered from associated autoimmune diseases (mainly Hashimoto's
 thyroiditis), compared with a smaller proportion of a control group including IBS patients
 (about 3%). Furthermore, we showed that serum samples of NCWS patients tested positive for
 anti-nuclear (ANA) in more than one third of the cases. However, that study included mainly
 patients evaluated in a retrospective manner and no other autoantibodies were evaluated apart
 from ANA.

 In the present study, we included a group of consecutive NCWS patients, diagnosed with DBPC
 wheat challenge, to evaluate a) the frequency of autoimmune diseases, b) the frequency and
 pattern of serum ANA and other non-organ-specific and/or organ-specific autoantibodies, and
 c) the possible correlations between autoimmune diseases and serum autoantibodies presence
 and other NCWS-related disease characteristics, in comparison with age- and sex- matched
 healthy blood donors and IBS patients unrelated to NCWS.
NCWS

 Inclusion criteria:

 -  resolution of symptoms on a standard elimination diet, without wheat, cow's milk,
 yeast, and other food(s) causing self-reported symptoms

 -  symptom reappearance on a DBPC wheat challenge. As in previous studies, a DBPC cow's
 milk protein challenge and other open food challenges were also performed

 -  age above 18 years and <65 years

 -  follow-up duration longer than 12 months after the initial diagnosis

 -  at least two outpatient visits during the follow-up period.

 Exclusion criteria:

 -  positive serum assays for celiac disease (i.e. anti-tissue transglutaminase (anti-tTG)
 IgA and anti-deamidated gliadin peptides (anti-DGP) IgG antibodies)

 -  presence of intestinal villous atrophy, documented in all the patients carrying the
 DQ2 and/or the DQ8 HLA haplotypes

 -  positive IgE-mediated immune-allergy tests to wheat (skin prick tests and/or specific
 serum IgE detection).

 IBS IBS diagnosis had been made in accordance with the Rome IV criteria and none of these
 patients improved on an elimination diet without wheat, cow's milk, egg, tomato or
 chocolate.