Computational Tools for the Reliability Assessment and the Engineering Design of Procedures and Devices in Bariatric Surgery.

Obesity is one of the main health concerns worldwide. Bariatric Surgery (BS) is the gold standard treatment for severe obesity. Nevertheless, unsatisfactory weight loss and complications can occur. The efficacy of BS is mainly defined on experiential bases; therefore, a more rational approach is required. The here reported activities aim to show the strength of experimental and computational biomechanics in evaluating stomach functionality depending on bariatric procedure. The experimental activities consisted in insufflation tests on samples of swine stomach to assess the pressure-volume behaviour both in pre- and post-surgical configurations. The investigation pertained to two main bariatric procedures: adjustable gastric banding (AGB) and laparoscopic sleeve gastrectomy (LSG). Subsequently, a computational model of the stomach was exploited to validate and to integrate results from experimental activities, as well as to broad the investigation to a wider scenario of surgical procedures and techniques. Furthermore, the computational approach allowed analysing stress and strain fields within stomach tissues because of food ingestion. Such fields elicit mechanical stimulation of gastric receptors, contributing to release satiety signals. Pressure-volume curves assessed stomach capacity and stiffness according to the surgical procedure. Both AGB and LSG proved to reduce stomach capacity and to increase stiffness, with markedly greater effect for LSG. At an internal pressure of 5 kPa, outcomes showed that in pre-surgical configuration the inflated volume was about 1000 mL, after AGB the inflated volume was slightly lower, while after LSG it fell significantly, reaching 100 mL. Computational modelling techniques showed the influence of bariatric intervention on mechanical stimulation of gastric receptors due to food ingestion. AGB markedly enhanced the mechanical stimulation within the fundus region, while LSG significantly reduced stress and strain intensities. Further computational investigations revealed the potentialities of hybrid endoscopic procedures to induce both reduction of stomach capacity and enhancement of gastric receptors mechanical stimulation. In conclusion, biomechanics proved to be useful for the investigation of BS effects. Future exploitations of the biomechanical methods may largely improve BS reliability, efficacy and penetration rate.

Occurrence of overt celiac disease in the elderly following total thyroidectomy.

We report the case of a female patient in whom gluten-induced entheropathy was revealed at the age of 71 yr by resistance to treatment with levothyroxine (L-T4), calcium carbonate and alfacalcidol. Hypothyroidism and hypoparathyroidism were the consequence of a total thyroidectomy performed at the age of 65 yr for a large multinodular goiter. Six months after thyroid ablation the patient started to complain of abdominal pain, diarrhea and weight loss. Following, anemia and osteopenia were documented. A progressive increase of replacement therapy for hypothyroidism and hypoparathyroidism was necessary. The clinical presentation suggested a malabsorption syndrome: celiac disease (CD) was diagnosed by serological markers and duodenal biopsy. Following gluten-free diet a normalization of clinical and serological findings was observed, bone mass density improved and a reduction of L-T4, calcium and vitamin D requirements was observed.

Possible pathogenetic relevance of interleukin-1 beta in "destructive" organ-specific autoimmune disease (Hashimoto's thyroiditis).

Thyroid follicular cells (TFC) abundantly express a variety of immunologically relevant surface molecules in Hashimoto's thyroiditis (HT), for example, MHC antigens and adhesion molecules such as ICAM-1. Cytokines produced by infiltrating type 1 helper and cytotoxic T cells are importantly involved in de novo expression or up-regulation of such molecules. We recently demonstrated that TFC from HT patients almost invariably bear on their surface two additive functional molecules: Fas/Apo1/CD95, an important participant in apoptosis, and B7.1, a member of a family of "co-stimulatory" molecules that are crucial for efficient antigen presentation. To date, 12 out of 14 surgical HT thyroid specimens that we studied by immunohistochemistry showed B7.1-positive TFC, and all showed Fas-positive TFC, different from Graves' disease (GD) or nonautoimmune specimens. We have investigated the role of a number of cytokines (IL-1 beta, TNF-alpha, IL-4, IL-6, IL-10, IL-12, TGF-beta 1, IFN-gamma) in regulating B7.1 and Fas expression. The experiments were performed by immunofluorescence flow cytometry on TFC purified from nontoxic goiter specimens which were Fas- and B7.1-negative at baseline, and one B7.1/Fas-positive HT specimen. IFN-gamma (500 U/mL) and TNF-alpha (200 ng/mL) were unable to induce de novo expression of B7.1 or Fas on cultured TFC. At higher doses (2000 U/mL and 800 ng/mL, respectively), they were unable to induce B7.1, but potentiated the spontaneous expression of Fas. Type 2 cytokines (IL-4 and IL-10) were unable to induce Fas or B7.1 on TFC at all, or to down-regulate Fas or B7.1 when expressed. On the other hand, IL-1 beta was the only cytokine able to induce Fas expression on Fas-negative TFC at doses ranging from 100 to 1000 pg/mL. Moreover, at a dose of 400 pg/mL, it was also able to induce B7.1. We demonstrated by immunohistochemistry that IL-1 beta is abundantly present on HT thyroids, including follicular structures. It is conceivable that IFN-gamma, or other cytokines secreted by infiltrating T-lymphocytes, are able to promote IL-1 beta secretion by TFC. In conclusion, a crucial role of IL-1 beta in "destructive" organ-specific autoimmunity may be suggested both for the perpetuation of the autoimmune reaction (induction of efficient autoantigen presentation by TFC, via co-stimulatory molecules) and in induction of tissue damage via "suicide" Fas/FasL-mediated TFC interaction.

Regulation of apoptosis in endocrine autoimmunity: insights from Hashimoto's thyroiditis and Graves' disease.

Dysregulation of apoptosis is associated with the pathogenesis of organ-specific autoimmune diseases, through altered target organ susceptibility. Apoptosis signaling pathways can be initiated through activation of death receptors such as Fas. A comparative analysis of the expression of Fas and FasL, the antiapoptotic molecule Bcl-2, and apoptosis in both thyrocytes and thyroid-infiltrating lymphocytes (TILs) from patients with either Graves' disease (GD) or Hashimoto's thyroiditis (HT) was performed. GD thyrocytes expressed less Fas than HT thyrocytes, whereas GD TILs had higher levels of Fas and FasL than HT TILs. GD thyrocytes expressed higher levels of Bcl-2 compared with HT thyrocytes. The opposite pattern was observed in GD (low Bcl-2) and HT (high Bcl-2) TILs. Consistently, thyrocyte apoptosis was marked in HT and poor in GD thyroids, and TIL apoptosis was marked in GD and poor in HT. Our findings suggest that in GD thyroid the regulation of Fas/FasL/Bcl-2 favors apoptosis of infiltrating lymphocytes. Moreover, the reduced levels of Fas/FasL and increased levels of Bcl-2 should favor thyrocyte survival and hypertrophy associated with stimulatory thyroid-stimulating hormone receptor antibodies. In contrast, the regulation of Fas/FasL/Bcl-2 expression in HT can promote thyrocyte apoptosis via homophylic Fas-FasL interactions, and a gradual reduction in thyrocyte numbers leading to hypothyroidism. Fas-mediated apoptosis may be a general mechanism of cell damage in destructive organ-specific autoimmunity.

Fibrillary glomerulonephritis in Castleman's disease.

Castleman's disease is an uncommon lymph node disorder which can be associated with renal disease. In this report we describe a patient with fever, weight loss, anorexia, increase in inflammatory proteins, anemia and nephrotic syndrome. Castleman's disease, plasma cell type, was diagnosed by histologic analysis after surgical excision of a pelvic lymph node. The disease was considered localized, since further investigations did not show any other pathologic mass. After resection of the pelvic lymphoid mass, clinical remission of systemic symptoms and laboratory abnormalities was observed, with the exception of the nephrotic syndrome. Renal biopsy was performed and showed a pattern compatible with fibrillary glomerulonephritis. Progressive decline in renal function was observed, despite immunosuppressive therapy.

Sensitization to food or inhalant allergens in pediatric patients. Clinical usefulness of first-level panel tests for specific IgE.

First-level in vitro diagnostic tests for specific IgE against common inhalant or food allergens have been used to identify allergic patients. We evaluated the performance of Phadiatop and Fx5 (mixed food allergens) serological tests (Pharmacia Diagnostics AB, Uppsala, Sweden) in different groups of pediatric patients. We studied two groups of pediatric patients: 61 children recruited from an Allergy and Clinical Immunology Unit (Group 1); 136 children from a Pediatric Unit not specifically devoted to allergic diseases (Group 2); the two groups comprised patients with (A) or without (B) clinical suspicion of allergic disease. Sera were collected from routine blood analysis. Frequencies of positivities for Phadiatop and/or Fx5 were very high (68.8%) in Group 1, however, as many as 35.5% of Group 2 children were positive, as well. All the patients of Group 1 with clinical suspicion of allergic disease (1A), confirmed by allergologic diagnostic tests, had a positive first-level test; 42.8% only of the patients in Group 2 with suspicion of allergic disease (2A) had a positive first-level test. None of the Phadiatop/Fx5-negative children of Group 2A had specific-IgE with conventional tests. In 30% of children not suspected for allergic diseases (1B and 2B), positive first-level tests were observed. Such unexpected positivities were confirmed by single specific-IgE assays in 94.7% (for inhalants) or 71% (for foods) of cases. In conclusion, altogether the sensitivity and overall performance of first-level tests in pediatric populations (especially for inhalant allergens) may suggest their use, under appropriate circumstances, both as a first diagnostic approach (to rule out negative patients) and for screening purposes.

Reduced priming effect of interleukin 3 on IgE mediated basophil histamine release in patients with systemic sclerosis.

OBJECTIVE: To determine the capacity of interleukin 3 (IL-3) to induce and enhance basophil histamine release in patients with systemic sclerosis (SSc). METHODS: Leukocyte suspensions prepared by dextran sedimentation of peripheral venous blood were stimulated with anti-IgE (10 microg/ml), N-formyl-methionyl-leucyl-phenylalanine (fMLP, 1 microM), and IL-3 (0.1 to 10 ng/ml). The priming effect of IL-3 on anti-IgE and fMLP induced histamine release was evaluated. Histamine release was measured by an automated fluorometric method. RESULTS: No significant difference was found between patients with SSc (n = 12) and control subjects (n = 16) regarding spontaneous IL-3 and fMLP induced histamine release. IL-3 was a weak basophil agonist in both populations, since net histamine release did not exceed 10% of total histamine content in any case. Anti-IgE induced histamine release was lower in patients with SSc than in controls (13.09 +/- 4.8 vs 30.2 +/- 6.2%; p = 0.048). IL-3 enhanced anti-IgE and fMLP induced histamine release in a dose dependent fashion. However, the enhancement of anti-IgE induced histamine release by IL-3 was significantly lower in patients with SSc than in controls (p < 0.01 at 0.1 ng/ml IL-3; p < 0.05 at 1 and 10 ng/ml IL-3). In contrast, no difference was found between the 2 populations regarding the enhancement of fMLP induced histamine release by IL-3. CONCLUSION: Basophil response to anti-IgE and the priming effect of IL-3 on IgE mediated basophil histamine release are lower in patients with SSc than in controls. These alterations could be related to chronic activation of the IgE/basophil system in patients with SSc.

Enhancement of basophil histamine release by interleukin-3: reduced effect in atopic subjects.

The inducing and enhancing effects of interleukin-3 (IL-3) on basophil histamine release in patients with respiratory allergy (n = 28) and in normal subjects (n = 22) were compared. Leukocyte suspensions, prepared by dextran sedimentation, were stimulated with anti-IgE (1/5000), N-formyl-methionyl-leucyl-phenylalanine (FMLP, 1 microM), and IL-3 (0.1-10 ng/ml), and histamine concentration was measured by an automated fluorometric method. A trend toward higher histamine release after challenge with anti-IgE, FMLP, and IL-3 was found in atopic subjects. Preincubation of basophils with IL-3 resulted in a dose-dependent increase of anti-IgE- and FMLP-induced histamine release, with a more marked effect in nonatopic than in atopic subjects. Mean net enhancement of anti-IgE-induced histamine release by 10 ng/ml IL-3 was 2.5 +/- 5% in atopic subjects and 29.6 +/- 4.2% in nonatopic subjects (P < 0.001). The enhancement of FMLP-induced histamine release by IL-3 was 10.3 +/- 3.9% in atopic patients and 29 +/- 2.4% in nonatopic subjects (P < 0.01). In atopic subjects, a negative correlation was found between anti-IgE- or FMLP-induced histamine release and net enhancement by IL-3 (r = -0.45, P < 0.02; r = -0.48, P < 0.01, respectively). The results of this study indicate that in atopic subjects IgE-mediated histamine release can scarcely be enhanced by a basophil response modifier such as IL-3. It is conceivable that the frequent basophil stimulation in atopic patients leads to a reduced sensitivity to the enhancing effect of IL-3.

Defective inhibition of sodium on basophil histamine release in patients with allergic rhinitis and bronchial asthma.

The aim of this study was to evaluate whether Na+ exerts its inhibitory effect on basophil histamine release induced by immunoglobulin E (IgE)-dependent (anti-IgE) and IgE-independent (N-formyl-methionyl-leucyl-phenylalanine (FMLP), interleukin-3 (IL-3)) stimuli in patients with allergic rhinitis (n = 24) and allergic bronchial asthma (n = 10). Peripheral blood leucocytes were stimulated with anti-IgE, FMLP and IL-3 in the presence of high and low Na+ concentrations, and histamine release was measured using a fluorometric method. In standard Na(+)-containing medium, spontaneous and stimulated histamine release was higher in allergic patients (n = 34) (both rhinitic and asthmatic) than in healthy subjects (n = 41). Na+ removal from extracellular medium and its isosmotic substitution with choline chloride or with N-methyl-D-glucamine led to a significant increase of anti-IgE-, FMLP- and IL-3-induced histamine release in normal subjects, but not in allergic patients. The increase in Na+ concentration in the extra-cellular medium was accompanied by a dose-dependent decrease of anti-IgE- and FMLP-induced histamine release in normal subjects, but not in allergic patients. The behaviour of atopics and healthy subjects was different and not related to the basophil responsiveness to activating signals. The incubation of basophils from healthy subjects with sera from allergic patients did not have a significant influence on the inhibitory effect of Na+. Basophils from healthy subjects and atopic patients respond differently when stimulated in a low Na+ medium. The reduced sensitivity to the inhibitory effect of Na+ may contribute to basophil dysfunction in patients with respiratory allergy.

N-acetyl-aspartyl-glutamic acid inhibits cellular recruitment and mediator release during the late allergen-induced nasal reaction.

OBJECTIVE: N-acetyl-aspartyl-glutamic acid (NAAGA) was effective in the treatment of allergic rhinitis, with an action on early allergen-induced nasal symptoms and mediator release. The aim of this study was to evaluate the clinical activity of NAAGA and its effects on the late antigen-induced reaction in the nose. METHODS: Ten patients with allergic seasonal rhinitis were included in this randomized double-blind crossover trial of a 6% wt/vol solution of NAAGA (daily dosage 84 mg) versus placebo (lactose). The drug and placebo were administered intranasally five times daily for 1 week, with a 2-week interval between treatments. RESULTS: Treatment with NAAGA, but not with placebo, significantly reduced the late antigen-induced nasal symptoms, mainly nasal obstruction. Eosinophil numbers in the nasal lavages collected 6 h and 24 h after challenge were significantly lower after NAAGA than after placebo. Active treatment also significantly reduced the neutrophil count 6 h after antigen challenge, and significantly lowered eosinophil cationic protein and myeloperoxidase levels in nasal lavages 6 h and 24 h after antigen challenge. CONCLUSION: These results indicate that treatment for 1 week with NAAGA can reduce the late antigen-induced reaction in the nose. This is accompanied by a reduction in eosinophil and neutrophil recruitment and release of eosinophil cationic protein and myeloperoxidase.

Granulocyte-macrophage colony-stimulating factor and interleukin-3 cause basophil histamine release by a common pathway: downregulation by sodium.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) are recognized as enhancers, but not as inducers, of histamine release from normal human basophils. However, when extracellular Na+ is removed IL-3 acquires the capacity to induce histamine release. The aim of this study was to evaluate whether GM-CSF can induce basophil histamine release using the same pathway of IL-3. Leucocyte suspensions from normal human subjects were stimulated with GM-CSF, IL-3 and anti-IgE, and histamine release was evaluated by an automated fluorometric method. In a physiological medium, GM-CSF (10 ng/ml) and IL-3 (10 ng/ml) did not provoke histamine release, in spite of an efficient response to anti-IgE (10 micrograms/ml). However, when extracellular Na+ was substituted iso-osmotically with N-methyl-d-glucamine+ or with choline+, GM-CSF and IL-3 were able to trigger histamine release from either mixed leucocyte suspensions or purified human basophils. The effect of GM-CSF on basophil histamine release was dose dependent, with optimal release at a dose of 1 ng/ml after incubation at 37 degrees for 60-120 min. The kinetics of IL-3-induced histamine release were similar, whereas anti-IgE-induced histamine release was more rapid, being almost maximal after incubation for 30 min. A good correlation was found between GM-CSF-induced and IL-3-induced histamine release; furthermore, the combined effects of the two cytokines were less than additive, suggesting that they share the same pathways leading to histamine release. When extracellular Na+ concentration was increased from 0 to 140 mm, histamine release induced by GM-CSF, IL-3 and anti-IgE was reduced progressively. In contrast, histamine release induced by these stimuli was upregulated when the concentration of extracellular Ca2+ was increased. These results provide indirect evidence that GM-CSF and IL-3 can induce basophil histamine release by a common pathway that is downregulated by Na+.

Nasal response to a single antigen challenge in patients with allergic rhinitis - inflammatory cell recruitment persists up to 48 hours.

BACKGROUND: Allergen challenge in some patients with respiratory allergy is followed by an early and a late reaction. OBJECTIVE: To evaluate the duration of mediator release and inflammatory cell recruitment during the late antigen-induced nasal response. METHODS: Eight patients with seasonal allergic rhinitis due to grass pollen underwent local challenge with the relevant allergen, a non-relevant allergen (Parietaria judaica), and nebulized saline solution. Nasal lavages were performed at baseline and 6, 24, 48, 72 h after challenge. Eosinophil cationic protein (ECP), leukotriene C4 (LTC4), leukotriene B4 (LTB4) myeloperoxidase (MPO) and prostaglandin D2 (PGD2) levels were radioimmunoassayed and histamine concentration was measured by an automated fluorometric method. RESULTS: Nasal challenge with the relevant antigen induced a response 6 h after stimulation, which subsided within 24 h. Eosinophilia, observed in the nasal lavages collected from 6 to 24 h after this challenge, was accompanied by ECP release. Neutrophilia were found in the nasal lavages collected from 6 to 24 h after challenge. The increase in neutrophil number correlated with MPO levels and LTB4 concentrations, but not with the intensity of nasal obstruction. Antigen challenge also induced significant recruitment of mononuclear cells 48 h after provocation. The challenge significantly raised histamine, but not PGD2, levels in the nasal lavages collected 6 h after provocation. A trend towards an increase in LTC4 levels in the nasal lavages collected 6 h after specific antigen challenge was also found. Nasal challenge with a non-relevant allergen or with saline solution did not cause either inflammatory cell recruitment or mediator release. CONCLUSION: Nasal challenge with the relevant antigen can induce a late response characterized by local accumulation of eosinophils, neutrophils and mononuclear cells persisting for 48 h and accompanied by release of ECP, MPO, LTB4 and histamine. These results indicate that a single antigen challenge in patients with allergic rhinitis causes prolonged inflammatory alterations which may contribute to the development of airway hyperreactivity.

Different intrathyroid expression of intercellular adhesion molecule-1 (ICAM-1) in Hashimoto's thyroiditis and Graves' disease: analysis at mRNA level and association with B7.1 costimulatory molecule.

Cultured thyroid epithelial cells can be induced to express intercellular adhesion molecule-1 (ICAM-1, or CD54). However, constitutive follicular expression of ICAM-1 has been reported only in thyroid autoimmunity. We evaluated the expression of ICAM-1 mRNA and protein on thyroid tissue from different autoimmune thyroid diseases, and its relationship with other immunologically relevant surface markers, namely costimulatory molecules of B7 family. Thyroid tissue sections were obtained by surgically removed thyroid glands from 6 patients with Hashimoto's thyroiditis (HT), 6 with Graves' disease (GD) and 3 with multinodular nontoxic goiter. We used in situ hybridization to localize ICAM-1 mRNA, and immunohistochemical analysis by alkaline phosphatase anti-alkaline phosphatase (APAAP) method. We showed a clear hybridization pattern, localized in follicular cells, in sections of glands with HT. The hybridization pattern was far less pronounced in GD: no staining was apparent on follicular cells. These results were strictly consistent with those obtained by means of immunohistochemistry. Moreover, double-staining experiments demonstrated colocalization of ICAM-1 and B7.1 molecules in HT, whereas no B7.1 expression was observed in Graves' or in non-autoimmune thyroid diseases. These data agree with the hypothesis of distinct immunoregulatory phenomena and effector mechanisms in the 2 main autoimmune thyroid diseases.

Priming and inducing effects of interleukin-3 on histamine release from cord-blood basophils.

The effect of interleukin-3 (IL-3) on histamine release from cord and adult blood basophils were evaluated. Leukocyte suspensions, obtained from adult patients with respiratory allergy (n = 15), normal adult subjects (n = 15), and neonates with (n = 15) and without (n = 19) atopic disposition, were stimulated with anti-IgE, fMLP, and IL-3. IgE-mediated histamine release was significantly higher in adult patients, either allergic or normal, than in neonates with or without atopic disposition. A trend toward higher fMLP-induced histamine release was found in allergic adult subjects. IL-3 had a weak direct histamine-releasing activity in allergic adult subjects and in neonates, but not in normal adult donors. A significant enhancing effect of IL-3 on histamine release induced by anti-IgE was observed in neonates with and without atopic disposition and in normal adult subjects, but not in atopic adult patients. IL-3 exerted a priming effect also when basophils were stimulated with fMLP, without any significant difference between neonates and adult subjects. Passive sensitization with IgE-rich serum resulted in a significant increase in anti-IgE-induced, but not in IL-3-induced, histamine release from cord-blood basophils. In conclusion, IL-3 primes cord-blood as well as adult blood basophils for a consecutive anti-IgE- or fMLP-induced histamine release and its activity is not limited by the low density of membrane IgE in cord-blood basophils.

Preliminary evidence for 'aberrant' expression of the leukocyte integrin LFA-1 (CD11a/CD18) on conjunctival epithelial cells of patients with mite allergy.

BACKGROUND: We have previously shown aberrant expression of the 'leukocyte' integrin LFA-1 on epithelial cells in chronic autoimmune thyroiditis. In the present study we investigated whether conjunctival epithelial cells, which bear the adhesion molecule ICAM-1 on their surface during allergic inflammation, may also aberrantly express its natural ligand, the 'leukocyte' integrin LFA-1. METHODS: We studied 13 patients with rhinoconjunctivitis allergic to mites, chronically exposed to the allergen, 11 patients allergic to pollen tested out of the pollen season and 8 normal volunteers. Single and double immunocytochemical staining of conjunctival smears was employed. RESULTS: LFA-1 staining on epithelial cells was demonstrated in 12/13 patients allergic to mites and not in normal controls or in patients allergic to pollen tested out of the pollen season. The epithelial localization of LFA-1 was confirmed by double staining with anti-LFA-1 and anti-cytokeratin antibodies (both immunocytochemical and immunofluorescence). CONCLUSIONS: Coexpression of LFA-1 and ICAM-1 during persistent allergen stimulation may be relevant for interaction between epithelial cells and activated effector cells, such as eosinophils, which bear on their surface both ICAM-1 and its beta2 integrin ligands.

Comparison of ELISA for tissue transglutaminase autoantibodies with antiendomysium antibodies in pediatric and adult patients with celiac disease.

BACKGROUND: Tissue transglutaminase (t-TG) is the main autoantigen recognized by the endomysium antibodies (EMA) observed in patients with celiac disease (CD). The aim of the study was to assess an ELISA method for t-TG antibodies (t-TGA) with respect to EMA IF assay in pediatric and adult patients. METHODS: t-TGA were analyzed by ELISA in 220 sera samples: 82 patients with biopsy-proven untreated CD (23 adults and 59 children), 14 CD children on gluten-free diet, 18 asymptomatic relatives of CD patients, and 106 age-matched control patients with gluten-unrelated gastrointestinal diseases (58 adults and 48 children). Serum IgA EMA were tested on umbilical cord sections in all patients. RESULTS: The great majority (92.7%) of untreated CD patients (both adults and children) were t-TGA positive (values ranging from 20.1 to > 300 AU). None of the child control patients and only two out of 58 (3.4%) of the adults with unrelated gastrointestinal diseases had serum t-TGA positivity; two out of 18 first-degree relatives with biopsy-proved silent CD were t-TGA (as well as EMA) positive. Finally, two out of 14 CD children, assuming a gluten-free diet, had serum t-TGA (as well as EMA). A highly significant correlation (P < 0.001) was observed between t-TGA concentrations and EMA. t-TGA showed a sensitivity of 87% and 95%, a specificity of 97% and 100% for adults and children, respectively. CONCLUSION: The method is highly sensitive and specific in the diagnosis of CD and is promising as a tool for routine diagnostic use and population screening, especially in children.

Use of an artificial neural network to predict Graves' disease outcome within 2 years of drug withdrawal.

BACKGROUND: Graves' disease (GD) is an autoimmune disorder characterized by hyperthyroidism, which can relapse in many patients after antithyroid drug treatment withdrawal. Several studies have been performed to predict the clinical course of GD in patients treated with antithyroid drugs, without conclusive results. The aim of this study was to define a set of easily achievable variables able to predict, as early as possible, the clinical outcome of GD after antithyroid therapy. METHODS: We studied 71 patients with GD treated with methimazole for 18 months: 27 of them achieved stable remission for at least 2 years after methimazole therapy withdrawal, whereas 44 patients relapsed. We used for the first time a perceptron-like artificial neural network (ANN) approach to predict remission or relapse after methimazole withdrawal. Twenty-seven variables obtained at diagnosis or during treatment were considered. RESULTS: Among different combinations, we identified an optimal set of seven variables available at the time of diagnosis, whose combination was useful to efficiently predict the outcome of the disease following therapy withdrawal in approximately 80% of cases. This set consists of the following variables: heart rate, presence of thyroid bruits, psycological symptoms requiring psychotropic drugs, serum TGAb and fT4 levels at presentation, thyroid-ultrasonography findings and cigarette smoking. CONCLUSIONS: This study reveals that perceptron-like ANN is potentially a useful approach for GD-management in choosing the most appropriate therapy schedule at the time of diagnosis.