Lidia Di Prima

A Cytologic Assay for Diagnosis of Food Hypersensitivity in Patients With Irritable Bowel Syndrome

BACKGROUND & AIMS A percentage of patients with symptoms of irritable bowel syndrome (IBS) suffer from food hypersensitivity (FH) and improve on a food-elimination diet. No assays have satisfactory levels of sensitivity for identifying patients with FH. We evaluated the efficacy of an in vitro basophil activation assay in the diagnosis of FH in IBS-like patients. METHODS Blood samples were collected from 120 consecutive patients diagnosed with IBS according to Rome II criteria. We analyzed in vitro activation of basophils by food allergens (based on levels of CD63 expression), as well as total and food-specific immunoglobulin (Ig)E levels in serum. Effects of elimination diets and double-blind food challenges were used as standards for FH diagnosis. RESULTS Twenty-four of the patients (20%) had FH (cows milk and/or wheat hypersensitivity); their symptom scores improved significantly when they were placed on an elimination diet. Patients with FH differed from other IBS patients in that they had a longer duration of clinical history, a history of FH as children, and an increased frequency of self-reported FH; they also had hypersensitivities to other antigens (eg, egg or soy). The basophil activation assay diagnosed FH with 86% sensitivity, 88% specificity, and 87% accuracy; this level of sensitivity was significantly higher than that of serum total IgE or food-specific IgE assays. CONCLUSIONS A cytometric assay that quantifies basophils after stimulation with food antigens based on cell-surface expression of CD63 had high levels of sensitivity, specificity, and accuracy in diagnosing FH. This assay might be used to diagnose FH in patients with IBS-like symptoms.

Chronic constipation and food intolerance: A model of proctitis causing constipation

Objective Chronic constipation in children can be linked to cows milk intolerance (CMI) but the existence of a food intolerance-dependent proctitis is still debated. The aim of this study was to evaluate the histologic data in patients with food intolerance-related constipation. Material and methods Fifty-two consecutive patients (22 M, median age 4 years) with chronic constipation unresponsive to common treatment were enrolled. All patients were put on a cows milk-free diet for 4 weeks and those uncured on this diet underwent a subsequent 4-week period of oligoantigenic diet. In the patients cured on elimination diet, a subsequent double-blind food challenge was performed to confirm the diagnosis of food intolerance. At entry to the study, routine hemato-chemical and immunologic assays, rectoscopy, and histologic study of the rectal mucosa were performed. In the patients cured on elimination diet, rectal histology was repeated when they were cured. Results Twenty-four patients were found to be suffering from CMI and 6 from multiple food intolerance. These patients had a normal stool frequency on elimination diet, while constipation reappeared on food challenge. The condition of the remaining 22 patients did not improve on elimination diet. The patients with food intolerance showed a significantly higher frequency of erosions of the mucosa, number of intraepithelial lymphocytes and eosinophils, and number of eosinophils in the lamina propria. Study of the rectal mucus gel layer showed that the food-intolerant patients had a significantly lower thickness than the other subjects studied. In the food intolerant patients, histologic abnormalities disappeared on elimination diet, when the patients were well. Conclusions Food intolerance-related constipation is characterized by proctitis with eosinophil infiltrate of the rectal mucosa. A reduced mucus gel layer can be considered a contributory factor in the pathogenesis of the constipation.

Autoimmune enteropathy and colitis in an adult patient.

The presence of circulating autoantibodies to gut enterocytes has been very rarely described in adults and is considered a possible cause of refractory sprue. Our aims was to describe the case of an adult patient with serum anti-enterocyte autoantibodies associated with a clinical picture characterized by involvement of both the small intestine and colon. A female, age 50, had suffered from diarrhea with mucus and blood, abdominal pain, thinness, anemia, and leukopenia since the age of 20. She also suffered from HCV infection and had mild chronic hepatitis. Family history was positive for autoimmunity. Symptoms were reported to worsen after eating gluten-containing foods, but anti-transglutaminase and anti-endomysial antibodies were negative. Intestinal histology showed mild, patch villous atrophy with a high intraepithelial lymphocyte count, but a normal number of intraepithelial lymphocytes carrying the gamma/delta+ receptor. HLA was: A11, A31 (19), B52 (5), DR 15 (2), DR 14 (6), DR 51, DR 52, DQ1. Colonoscopy did not show ulcerations or erosions and colon histology showed a moderate inflammatory infiltrate without minor crypt distortion or granuloma. RAST tests were positive for lactalbumin, lactoglobulin, casein, egg, and gliadin. After commencement of an oligoantigenic diet, stool frequency initially decreased, but the presence of mucus in the stools persisted, with episodes of bloody diarrhea. After one year of diet, nutritional parameters were low and anemia associated with a low leukocyte count persisted. Upper and lower gastrointestinal endoscopy and histology of the small intestine and colon were virtually unchanged. Consequently, natural autoantibodies and enterocyte autoantibodies were assayed. The patient was positive for IgG class enterocyte autoantibodies at a titer of 1:34. No other organ-specific or non-organ-specific autoantibodies were positive. Prednisolone treatment was started and the symptoms improved. After one year of this treatment plus elimination diet she was reevaluated. Bowel movement frequency was normal, body weight increased, and the asthenia had completely regressed. IgG anti-enterocyte autoantibodies were absent. Histology of the distal duodenum showed a normal villus/crypt ratio and IEL infiltration was reduced. Colon histology showed a reduction in inflammatory infiltrate in the lamina propria. In conclusion, we report a case of generalized gut disorder in an adult patient, affecting both the small intestine and the colon and characterized by the presence of circulating anti-enterocyte autoantibodies. Systematic testing for enterocyte autoantibodies should be performed not only in patients with refractory sprue, but also in subjects with upper and lower intestinal symptoms who have not been definitively diagnosed.

Usefulness of the organ culture system in the in vitro diagnosis of coeliac disease: A multicentre study

Objective. Diagnosis of coeliac disease is based on the presence of villous atrophy which recovers following a gluten-free diet. The presence of circulating antiendomysial antibodies as well as their disappearance after a gluten-free diet supports the diagnosis. It has also been demonstrated that antiendomysial antibodies are detectable in supernatants of cultured intestinal biopsies from patients with coeliac disease. The objective of this study was to compare the histology and antiendomysial antibodies in culture supernatants of intestinal biopsies to validate the in vitro organ culture system as a future diagnostic tool for coeliac disease. Material and methods. Seventy-five antiendomysial serum-positive patients on a gluten-containing diet were evaluated. Patients underwent endoscopy with 5 biopsy fragments: 3 for histology, 1 cultured with and the other without gliadin-peptide activator. Antiendomysial antibodies were evaluated in all culture supernatants. Results. Sixty-eight patients had evidence of villous atrophy, while 73 out of 75 were positive to the organ culture system. The agreement rate between organ culture and histology results was 94%. Conclusions. As all the centres participating in the study obtained good agreement between organ culture and histology results, the new system could be considered a reliable tool for the diagnosis of coeliac disease. Nevertheless, it is possible to highlight cases with an organ culture-positive and -negative histology. This feature could be of considerable interest because, as the sensitivity of organ culture seems to be greater than the initial histology, the new system might be useful in uncertain cases where the risk of missing the diagnosis of coeliac disease is high.

Searching for wheat plants with low toxicity in celiac disease: Between direct toxicity and immunologic activation.

BACKGROUND Natural or induced variations in the noxiousness of gluten proteins for celiac disease (CD) patients are currently being investigated for their potential in breeding wheat crops with reduced toxicity. AIMS We evaluated the bread wheat line C173 for its effects on the in vitro-grown duodenal mucosa of CD patients. METHODS In vitro-grown duodenal mucosa biopsies of 19 CD patients on a gluten-free diet were exposed to peptic/tryptic-digested prolamins from bread wheat line C173 lacking gliadin-glutenin subunits, analyzed for morphology, cytokine and anti-tTG antibody production, and compared with mucosa biopsies exposed to prolamins from wild-type cv. San Pastore. RESULTS Duodenal mucosa biopsies exposed to prolamins from C173 and San Pastore released higher amounts of IFN-γ, IL-2, IL-10 and anti-tTG antibodies in the culture medium than untreated controls. The line C173 differed from cv. San Pastore as it did not produce negative effects on enterocyte height, suggesting that manipulating prolamin composition can affect innate immune responses of CD mucosa to wheat gluten. CONCLUSIONS Our data demonstrated that this gliadin-deficient wheat has a lower direct toxicity but activates an immunologic reaction of the duodenal mucosa like that of the common wheat species.

Antiendomysium antibodies assay in the culture medium of intestinal mucosa: an accurate method for celiac disease diagnosis.

Background Celiac disease (CD) diagnosis is becoming more difficult as patients with no intestinal histology lesions may also be suffering from CD. Aim To evaluate the diagnostic accuracy of antiendomysium (EmA) assay in the culture medium of intestinal biopsies for CD diagnosis. Patients and methods The clinical charts of 418 patients with CD and 705 non-CD controls who had all undergone EmA assay in the culture medium were reviewed. Results EmA assay in the culture medium had a higher sensitivity (98 vs. 80%) and specificity (99 vs. 95%) than serum EmA/antibodies to tissue transglutaminase (anti-tTG) assay. All patients with CD who were tested as false-negatives for serum EmA and/or anti-tTG (32 adults and 39 children) carried the human leukocyte antigen alleles associated to CD. Furthermore, during the follow-up, four patients with negative-serum EmA/anti-tTG, normal villi architecture, and positive-EmAs in the culture medium, developed villous atrophy and underwent gluten-free diet with consequent resolution of the symptoms and complete intestinal histology recovery. Conclusion EmA assay in the culture medium should be included in the diagnostic criteria for CD diagnosis in ‘seronegative’ patients.

Multiple food hypersensitivity as a cause of refractory chronic constipation in adults

Chronic constipation that is unresponsive to laxative treatment is a severe illness, but children unresponsive to laxatives have been successfully treated with an elimination diet. We report the first cases of refractory chronic constipation caused by food hypersensitivity in adults. Four patients with refractory constipation who were unresponsive to high doses of laxatives were put on an oligo-antigenic diet and underwent successive double-blind, placebo-controlled, food challenges (DBPFC). Routine laboratory tests, immunological assays, colonoscopy, esophago-gastroduodenoscopy and rectal and duodenal histology were performed. While on an elimination diet, bowel habits normalized in all patients and a DBPFC challenge triggered the reappearance of constipation. In comparison with another 13 patients with refractory constipation unresponsive to the elimination diet, observed over the same period, the patients with food-hypersensitivity-related constipation had the following characteristics: longer duration of illness (p<0.03), lower body mass index (p<0.03), higher frequency of self-reported food intolerance (p<0.01), higher frequency of nocturnal abdominal pain and anal itching (p<0.01). In patients with food hypersensitivity, hemoglobin concentrations and peripheral leukocytes were lower than those in controls (p<0.03). The duodenal and rectal mucosa histology showed lymphocyte and eosinophil infiltration, and the duodenal villi were flattened in two cases. In adult patients, refractory chronic constipation may be caused by food hypersensitivity and an elimination diet is effective in these subjects.

Plasma calprotectin levels in patients suffering from acute pancreatitis.

Calprotectin (Cal) concentration is elevated in acute inflammatory reactions and its increase in the plasma suggests a diagnostic potential for Cal assay. This study aimed (a) to evaluate the Cal plasma levels in patients suffering from acute pancreatitis (AP) and (b) to assess whether early assay of Cal plasma levels can be helpful in assessment of the severity of AP. Forty-six consecutive patients, median age 45 years, suffering from a first attack of AP were recruited at two medical centers. Data collected on admission included age, sex, delay between pain onset and admission, and Glasgow score. A severe outcome was defined according to the Atlanta criteria. AP was defined as edematous or necrotic according to the CT findings. Plasma Cal and serum C reactive protein (CRP) were assayed in all patients within the first 24 hr after hospitalization. Sixty subjects suffering from blood hypertension were recruited as controls. Plasma Cal was measured by a commercial ELISA system. In all AP patients and in none of the controls, plasma Cal concentration was higher than the normal limit. Cal values in AP patients were significantly higher than in controls (P < 0.0001). There was not a statistically significant difference in Cal values between patients with severe and patients with mild AP. Plasma Cal values did not differ in necrotizing and edematous AP. During the follow-up plasma Cal was reassayed in six of the patients with abdominal fluid collection and the values were higher in the two patients with infected necrosis. We conclude that plasma Cal is elevated in patients with AP but it is not a useful marker for early prediction of pancreatitis severity. Further studies could evaluate its usefulness in pancreatic infected necrosis.

Screening for Celiac Disease in Non-Hodgkin's Lymphoma Patients: A Serum Anti-Transglutaminase–Based Approach

Several studies have shown the existence of an association between celiac disease (CD) and non-Hodgkins lymphoma (NHL). Our aim was to evaluate the usefulness of the serum anti-tissue transglutaminase (anti-tTG) antibody assay in screening for CD in consecutive NHL patients. In all, 80 consecutive patients (median age 61 years) with a new diagnosis of NHL were included. To compare the frequency of CD and of positive results for the anti-tTG assay, we enrolled 500 blood donors. In all patients serum anti-tTG was determined with two different ELISA: one based on tTG from guinea pig (gp-tTG) and the other based on human recombinant t-TG (h-tTG) as the antigens. Serum anti-endomysial antibodies (EmA) were also assayed. Subjects with positive serum EmA and/or anti-tTG underwent intestinal biopsy for histology study, HLA-DQ phenotype determination, and serum anti-gliadin (AGA) assay. Eight of 80 (10%) NHL patients were positive for anti-tTG ELISA—two of these exclusively for anti-gp-tTG and six for anti-h-tTG (7.5%). None of the 80 NHL patients were positive for serum EmA. The frequency of anti-tTG positivity in the blood donor controls was 2/500 (0.4%), significantly lower than that observed in the NHL patients (P < 0.0001). Both these blood donors were found to have CD. Only in one anti-h-tTG-positive NHL patient was there intestinal mucosa atrophy, and follow-up confirmed a CD diagnosis (CD frequency in NHL patients is 1.2%; versus blood donors: P = 0.4). In all the other seven anti-tTG-positive NHL patients a normal intestinal architecture was found, although, inflammatory infiltration of the lamina propria was observed in four patients. No anti-tTG-positive NHL patients, including the subject diagnosed as having CD, had a family history of CD, and all had normal weight and no signs of malabsorption. Anti-tTG false positive results were associated with a higher frequency of serum autoantibody positivity and T-cell type NHL. In conclusion, NHL patients the anti-tTG assay often gives discordant data with the EmA assay, with a high frequency of anti-tTG false positive results for CD diagnosis.

Clinical symptoms in celiac patients on a gluten-free diet

Objective. Persistent villous atrophy in patients with celiac disease (CD) on a gluten-free diet (GFD) is reported with increasing frequency. The aim of this study was to evaluate a possible association between persistent damage of the villi and “atypical” gastrointestinal symptoms in CD patients on a GFD. Material and methods. Sixty-nine CD patients on a GFD were divided into two groups: Group A included 42 patients (6 M, 36 F, age range 17–62 years) undergoing esophagogastroduodenoscopies (EGDs) due to the presence of symptoms; Group B included 27 control patients (6 M, 21 F, age range 24–71 years) who were asymptomatic at the time of the study. Both groups underwent EGDs and a duodenal histologic study. Results. Persistent endoscopic lesions were more frequent in Group A (30/42) than in Group B (12/27; p=0.01). Villous atrophy was significantly more frequent in Group A than in Group B: 85% versus 33% (p<0.0001; odds ratio (OR)=12; 95% CI 3.7–38.9). Gastrointestinal symptoms in the Group A patients were different from those present at CD diagnosis: anemia/diarrhea/weight loss in 6 cases; gastroesophageal reflux disease (GERD)-like symptoms in 12 cases; abdominal pain/constipation in 24 cases. In Group A there was no difference in gender distribution, age and duration of GFD between subjects with normal villi and those with persistent partial villous atrophy. Patients with persistent symptoms showed a higher intraepithelial eosinophil count (p=0.005) than the asymptomatic patients (p=0.01). Conclusions. Persistent intestinal villous atrophy in CD patients on a GFD is associated with gastrointestinal symptoms considered “atypical” for CD and not present at CD diagnosis.