Diagnostic role and clinical correlates of anti-Saccharomyces cerevisiae antibodies (ASCA) and anti-neutrophil cytoplasmic antibodies (p-ANCA) in Italian patients with inflammatory bowel diseases

BACKGROUND

Anti-Saccharomyces cerevisiae antibodies (ASCA) and perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) are serological markers associated, respectively, with Crohn's disease and ulcerative colitis, whose clinical significance and possible diagnostic role are still poorly defined.

AIMS

(a) To evaluate the sensitivity, specificity and predictive values of isolated and combined ASCA and p-ANCA assays in a large cohort of Italian patients with inflammatory bowel disease (IBD) and (b) to assess whether their presence is associated with particular clinical features of the disease.

PATIENTS AND METHODS

Hundred and forty-six IBD patients (93 with Crohn's disease and 53 with ulcerative colitis) and 54 control patients were enrolled in the study. ASCA (IgA and IgG) and p-ANCA were determined by means of enzyme-linked immunosorbent assay and indirect immunofluorescence, respectively.

RESULTS

The specificities were excellent for both tests (ASCA in Crohn's disease, 98.1% both for IgA and IgG, and p-ANCA in ulcerative colitis, 92.5%); however, the sensitivities of both tests were low (59.1% for ASCA IgA, 44.1% for ASCA IgG, 39.6% for p-ANCA). ASCA specificity and positive predictive value reached 100% when positivity for both IgA and IgG was present. No significant association was found between the presence of a specific serological marker and patients' clinical features.

CONCLUSIONS

This study confirms the low prevalence of p-ANCA observed in ulcerative colitis patients from the Mediterranean area. The low sensitivity of ASCA and p-ANCA, despite their rather high specificity, renders them of little value in the screening of the general population, where the prevalence of IBD is low. However, in our series, a double positivity for ASCA IgA and IgG identifies with certainty the presence of Crohn's disease.

Toxicity of copper-spiked sediments to Tubifex tubifex (Oligochaeta, Tubificidae): a comparison of the 28-day reproductive bioassay with a 6-month cohort experiment

Results from a 28-day adult reproductive bioassay using the aquatic oligochaete Tubifex tubifex (Müller, 1774) are compared with life table statistics obtained from a 6-month experiment on cohorts of the same species. This was done by simultaneously performing the two tests on copper spiked sediments. Five concentrations and a control were tested. The 28-day bioassay was performed 3 times in succession. Several endpoints were considered for each test and LOEC, IC10 and IC50 were calculated. IC50 estimates for the number of young produced in the 28-day bioassay range from 81 to 107 mg/kg; IC50 estimates for different endpoints of the cohort experiment ranged from 88 to 106 mg/kg. The 28-day bioassay showed essentially the same sensitivity as the cohort experiment to copper. This suggests that the 28-day reproductive bioassay does provide information that is relevant in assessing long-term toxic effects at the population level.

Activated platelets are the source of elevated levels of soluble CD40 ligand in the circulation of inflammatory bowel disease patients

BACKGROUND

The CD40/CD40L system, a key regulator and amplifier of immune reactivity, is activated in inflammatory bowel disease (IBD) mucosa.

AIMS

To determine whether plasma levels of sCD40L are elevated in Crohn's disease (CD) and ulcerative colitis (UC) patients compared with normal controls, to investigate the cellular source of sCD40L, and to explore CD40L induction mechanisms.

PATIENTS

CD, UC, and normal control subjects were studied.

METHODS

The concentration of sCD40L in plasma and supernatants of freshly isolated platelets and autologous peripheral blood T cells (PBT) was measured by ELISA. Surface CD40L expression level was measured by flow cytometry in resting and thrombin activated platelets, and unstimulated and CD3/CD28 stimulated PBT before and after coculture with human intestinal microvascular endothelial cells (HIMEC).

RESULTS

Compared with normal controls, plasma sCD40L levels were significantly higher in both CD and UC patients and proportional to the extent of mucosal inflammation. Platelets from IBD patients displayed a significantly higher surface CD40L expression than those from control subjects, and released greater amounts of sCD40L than autologous PBT. Contact with IL-1beta activated HIMEC induced significant upregulation of CD40L surface expression and release by platelets.

CONCLUSIONS

Elevated levels of sCD40L in the circulation of IBD patients reflect enhanced surface expression and release of CD40L by platelets. This phenomenon translates to an increased platelet activation state apparently induced by passage through an inflamed mucosal microvascular bed, a conclusion supported by the positive correlation of plasma sCD40L levels with the extent of anatomical involvement by IBD. These results suggest that platelet-endothelial interactions critically contribute to activation of the CD40 pathway in IBD.

Activated platelets are the source of elevated levels of soluble CD40 ligand in the circulation of inflammatory bowel disease patients

BACKGROUND

The CD40/CD40L system, a key regulator and amplifier of immune reactivity, is activated in inflammatory bowel disease (IBD) mucosa.

AIMS

To determine whether plasma levels of sCD40L are elevated in Crohn's disease (CD) and ulcerative colitis (UC) patients compared with normal controls, to investigate the cellular source of sCD40L, and to explore CD40L induction mechanisms.

PATIENTS

CD, UC, and normal control subjects were studied.

METHODS

The concentration of sCD40L in plasma and supernatants of freshly isolated platelets and autologous peripheral blood T cells (PBT) was measured by ELISA. Surface CD40L expression level was measured by flow cytometry in resting and thrombin activated platelets, and unstimulated and CD3/CD28 stimulated PBT before and after coculture with human intestinal microvascular endothelial cells (HIMEC).

RESULTS

Compared with normal controls, plasma sCD40L levels were significantly higher in both CD and UC patients and proportional to the extent of mucosal inflammation. Platelets from IBD patients displayed a significantly higher surface CD40L expression than those from control subjects, and released greater amounts of sCD40L than autologous PBT. Contact with IL-1beta activated HIMEC induced significant upregulation of CD40L surface expression and release by platelets.

CONCLUSIONS

Elevated levels of sCD40L in the circulation of IBD patients reflect enhanced surface expression and release of CD40L by platelets. This phenomenon translates to an increased platelet activation state apparently induced by passage through an inflamed mucosal microvascular bed, a conclusion supported by the positive correlation of plasma sCD40L levels with the extent of anatomical involvement by IBD. These results suggest that platelet-endothelial interactions critically contribute to activation of the CD40 pathway in IBD.

Unsuspected ileal stenosis causing obscure GI bleeding in patients with previous abdominal surgery--diagnosis by capsule endoscopy: a report of two cases

Peri-anastomotic ulcerations may occur in patients with previous abdominal surgery. They may present only with obscure GI bleeding. We report two cases in whom capsule endoscopy identified postsurgical stenoses with ulcers as the cause of obscure GI bleeding. Case 1. A 57-year-old male operated on in 1970 for a post-traumatic diaphragm hernia followed by displacement of the caecum in the upper left abdominal quadrant. Case 2. A 32-year-old female with a salpingectomy for tuberculosis (1978) followed by segmental ileal resection for intestinal obstruction. Both patients had undergone extensive work-up including bidirectional endoscopies and enteroclysis with negative results. Capsule endoscopy with the GIVEN diagnostic system was done. Ileal stenoses with mucosal ulcers in dilated prestenotic loops were observed in both cases. The capsule was retained at the stenosis site, requiring ileal resection and anastomosis. Pathology reports showed mucosal ulcers. In case 2, tuberculosis was ruled out by tissue and faecal polymerase chain reaction and culture. Ileal stenoses with prestenotic ulcerations causing GI bleeding may occur in patients with previous abdominal surgery. Capsule endoscopy may clarify the diagnosis and shorten the diagnostic work-up. However, these patients should be warned that capsule retention requiring surgery might occur.

Review article: diagnosis, monitoring and treatment of distal colitis

The diagnostic work-up of ulcerative colitis at presentation is based on the collection of clinical, microbiological, radiological, endoscopic and histologic data. Serological markers are characterized by too low a sensitivity to be commonly utilized in clinical practice. Although endoscopic and histologic features are characterized by very high sensitivity and specificity for the diagnosis of ulcerative colitis, negative stool cultures and parasites are mandatory to exclude an infectious aetiology at presentation. The treatment of choice of an acute flare-up of distal ulcerative colitis is represented by oral or topical mesalazine, or a combination of both, whereas the use of topical or systemic steroids should be restricted to patients who prove to be refractory to first-line treatments. Preliminary data suggest that the achievement of endoscopic and histologic remission after an acute flare of the disease might be associated with a prolonged remission.

Val34Leu factor XIII polymorphism in Italian patients with inflammatory bowel disease

BACKGROUND

Coagulation Factor XIII is implicated in fibrin stabilization and wound healing. Plasma levels of Factor XIII are reduced in inflammatory bowel disease patients; recently, a valine 34 to leucine polymorphism of the Factor XIII-A subunit gene with a defined protective effect against thrombosis and as yet undetermined effect on wound healing has been described.

AIM

To evaluate Val34Leu Factor XIII polymorphism distribution and to find possible correlations with clinical features in Italian inflammatory bowel disease patients.

STUDY POPULATION

A total of 152 inflammatory bowel disease patients, 90 with ulcerative colitis and 62 with Crohn's disease and 130 healthy volunteers were studied.

METHODS

Val34Leu polymorphism was detected by RFLP with BsaH I. Statistical analysis was performed by means of Fisher exact test.

RESULTS

In inflammatory bowel disease, 57.2% of patients showed the wild type status, 37.5% were heterozygous and 5.3% were homozygous for the 34Leu allele; the frequency of the mutated allele was 24.0%. In controls, 66.1% of subjects showed the wild type status, 28.5% were heterozygous and 5.4% were homozygous for the 34Leu allele; the frequency of the mutated allele was 19.7%. There was no difference in genotype distribution and prevalence of the mutated allele between inflammatory bowel disease patients and controls.

CONCLUSIONS

The present data do not show any differences in Val34Leu Factor XIII polymorphism distribution between inflammatory bowel disease patients and controls. The prothrombotic state described in inflammatory bowel disease patients does not depend on an altered distribution of Val34Leu Factor XIII polymorphism.

High rate of positive anti-tissue transglutaminase antibodies in chronic liver disease. Role of liver decompensation and of the antigen source

BACKGROUND

Since the recognition of tissue transglutaminase (tTG) as the target antigen of anti-endomysium antibodies, several ELISA assays using either guinea pig or human recombinant tTG have been developed. The aim of the study was to compare the behaviour of anti-tTG and anti-endomysium antibodies assays in coeliacs and in patients with chronic liver disease.

METHODS

34 patients (24 women, 34.9 +/- 12.5 years) with coeliac disease and 41 with chronic liver disease (14 women, 57 +/- 11.2 years), including 19 cirrhotics, were evaluated for anti-endomysium antibodies by indirect immunofluorescence and for anti-tTG IgA antibodies by ELISA, using guinea pig liver or human recombinant transglutaminase.

RESULTS

The prevalences of anti-tTG and anti-endomysium antibodies were 100% in patients with coeliac disease at diagnosis, 75% and 64.3% in patients on a gluten-free diet. All liver disease patients were negative for anti-endomysium antibodies, while 11 (26.8%) were positive for anti-tTG. All these patients had liver cirrhosis and represented 57.9% of all cirrhotics. The presence of anti-tTG was associated with higher Child-Pugh scores. The use of human transglutaminase determined a reduction in the rate of positive results; however, the rate of positive anti-tTG was still 17.1% in all liver disease patients and 31.6% in cirrhotics.

CONCLUSIONS

Our data confirm that anti-tTG have a similar sensitivity compared with anti-endomysium antibodies assay in coeliacs. However, a high prevalence of positive anti-tTG results is observed in cirrhotic patients, even when human recombinant tTG is used. The high prevalence of positive results among cirrhotic patients is associated with more advanced liver disease.

Inappropriate pemoline therapy leading to acute liver failure and liver transplantation

A 36-year-old female, presenting with jaundice, developed acute liver failure requiring orthotopic liver transplantation. On admission, none of the known causative factors for acute hepatitis, including use of drugs, were found to be present. Several days after hospitalization, the patient admitted taking therapy prescribed by a "non-traditional" physician, that she had been using for several years due to overweight and which had recently been modified with the introduction of pemoline. A considerable body of evidence exists in the medical literature showing that pemoline, which is a central nervous system stimulant, has variable hepatotoxic effects, ranging from a mild transient increase of serum transaminases to liver failure, including some lethal cases.

Acute encephalopathy as a primary manifestation of haemophagocytic lymphohistiocytosis

Haemophagocytic lymphohistiocytosis (HLH) is characterized anatomically by an infiltration of multiple tissues with lymphocytes and haemophagocytic histiocytes. First symptoms are usually hepatosplenomegaly, pancytopenia, and intractable fever. Up to 73% of those with HLH develop CNS involvement during the disease course. The peculiarity of the two patients presented here, a 20-month-old Italian female and a 4-year-old Moroccan female, is that the initial presenting neurological symptoms mimicked an encephalitis, anticipating the typical systemic symptoms by 1 and 4 months. They developed progressive encephalopathy accompanied by status epilepticus, one child developed a secondary hydrocephalus. In both children it was not possible to detect an underlying infection or malignant disease and there were no other cases in the family that suggested a familial form of HLH. Diagnosis and initiation of treatment was delayed because of the initial encephalopathic clinical picture and the late onset of the typical systemic features. As early diagnosis allows better therapeutical approaches, haemophagocytic lymphohistiocytosis should be considered in children with persistent or progressive findings of encephalopathy, especially in the absence of identification of a plausible pathogen.

Reduced free protein S levels in patients with inflammatory bowel disease: prevalence, clinical relevance, and role of anti-protein S antibodies

We evaluated free plasma levels of protein S, a natural anticoagulant factor, the prevalence of anti-protein S antibodies, a possible cause of protein S deficiency, and their correlation with anti-phospholipid antibodies in 53 patients with inflammatory bowel disease (IBD) and 53 age- and sex-matched controls. Mean free plasma protein S levels (+/- SD) were significantly lower in IBD patients (0.98+/-0.32 IU/ml) than in controls (1.06+/-0.28 IU/ml) (P < 0.05); only one patient showed protein S deficiency. Specific antibodies to protein S were found in four IBD patients (7.5%) and in one control (1.9%) (P = NS). Five IBD patients (9.4%) and none of the controls showed anti-phospholipid antibodies (P < 0.06). No correlation was found between free protein S levels and anti-protein S antibodies or between anti-protein S and anti-phospholipid antibodies. In conclusion, free plasma protein S levels are slightly but significantly decreased in IBD patients. The prevalence of anti-protein S and antiphospholipid antibodies is increased in IBD patients. Anti-protein S antibodies do not appear to determine low protein S levels or to overlap with or belong to anti-phospholipid antibodies.

Oral versus combination mesalazine therapy in active ulcerative colitis: a double-blind, double-dummy, randomized multicentre study

BACKGROUND

Oral and topical mesalazine formulations are effective in active ulcerative colitis, but little is known on the efficacy of combined treatment.

AIM

To compare the efficacy of oral mesalazine vs. combined oral and topical mesalazine in mildly to moderately active ulcerative colitis.

METHODS

Patients with mildly to moderately active ulcerative colitis (Clinical Activity Index, CAI 4-12) were identified at 15 participating centres. They were randomized to receive either mesalazine 4 g orally plus placebo enema, or mesalazine 2 g orally plus mesalazine 2 g rectally as a liquid enema for 6 weeks. The rate of clinical remission (CAI < 4) or clinical remission/improvement (reduction of CAI of 50% from baseline) at 6 weeks and time to clinical remission/improvement were primary end-points; the rate of endoscopic remission was a secondary end-point.

RESULTS

67 patients were assigned to oral treatment and 63 to combined treatment. One patient in the oral group and 2 in the combined group discontinued the treatment due to adverse events. Following an intention-to-treat analysis, the rate of clinical remission was 82% for oral treatment and 87% for combined treatment (P=0.56); the mean time to remission 22.2 and 20.2 days, respectively (P=0.29); the rate of clinical remission/improvement and the rate of endoscopic remission were 85% and 91% (P=0.503) and 58% and 71% (P=0.21), respectively.

CONCLUSIONS

In patients with mild active ulcerative colitis, mesalazine 4 g orally and 2 g orally plus 2 g enema are equally effective in inducing disease remission.

Contribution of immunofluorescence to the identification and characterization of anti-neutrophil cytoplasmic autoantibodies. The role of different fixatives

OBJECTIVE

To study the sera from selected groups of antineutrophil cytoplasmic antibody (ANCA) positive patients by means of the indirect immunofluorescence test (ANCA-IIF) with different fixatives, in order to better discriminate among the various ANCAs (Ag-specificity and disease associations), especially those for which the antigen targets have not yet been identified.

METHODS

Eighty pathological serum samples and 15 normal sera were evaluated. Pathological samples included sera from 30 ulcerative colitis (UC) ANCA positive patients, 30 P-ANCA/myeloperoxidase (MPO-ANCA) positive microscopic polyangiitis (MPA) patients, 10 C-ANCA/proteinase 3 (PR3-ANCA) positive Wegener's granulomatosis (WG) patients, and 10 antinuclear antibody (ANA) positive (ANCA negative) systemic lupus erythematosus (SLE) patients. ANCA were detected by IIF on ethanol, methanol and formalin-fixed granulocytes and by ELISAs specific for MPO, PR3, lactoferrin (LF) and bactericidal/permeability-increasing protein (BPI). Additionally, sera were tested for the presence of antinuclear antibodies on IIF.

RESULTS

96% of serum samples from UC patients, positive by IIF on ethanol-fixed granulocytes, became negative when tested on formalin-fixed neutrophil slides. On the contrary, 95% of sera from vasculitic patients showed a clear diffuse granular cytoplasmic pattern on the same substrate; sera from all 10 SLE patients did not show any reactivity when formalin was used as fixative. On methanol-fixed neutrophils, 100% of UC P-ANCA positive sera were positive with the same pattern versus only 20% of vasculitic P-ANCA positive (MPO positive). Methanol fixation had no effect on PR3-ANCA and ANA positive sera.

CONCLUSION

The comparison of IIF patterns of sera tested on different fixed cells may be useful to distinguish vasculitis-related P-ANCA versus ANA and vasculitis-related P-ANCA versus UC-related P-ANCA.

Sympathetic activity and blood pressure pattern in autosomal dominant polycystic kidney disease hypertensives

To study the potential role of sympathetic activity in the pathogenesis of arterial hypertension associated with autosomal dominant polycystic kidney disease (ADPKD) and to analyze its relationship with 24-hour blood pressure pattern, plasma catecholamines and 24-hour ambulatory blood pressure monitoring were evaluated in 30 ADPKD hypertensive patients (of which 17 without and 13 with renal failure) and in 50 essential hypertensives. The groups were matched for sex, body mass index, known duration of hypertension, and clinic blood pressure. Plasma catecholamines, determined in resting position, were higher in ADPKD patients without renal failure than in essential hypertensives. Nighttime diastolic blood pressure was higher and the percentage day-night difference in mean blood pressure was lower in hypertensives with ADPKD compared to patients with essential hypertension. Blood pressure was significantly correlated with plasma noradrenaline in ADPKD patients, independently of renal function. No significant differences were observed between ADPKD patients with and without renal failure, with respect to plasma catecholamines, 24-hour daytime and nighttime ambulatory blood pressures and the percentage day-night difference in mean blood pressure.

Inflammatory bowel diseases are not associated with major hereditary conditions predisposing to thrombosis

Patients with inflammatory bowel diseases (IBD) are at increased risk for thromboembolic complications. Our aim was to evaluate whether the increased risk for thrombosis in IBD could be due to a genetic association of IBD with hereditary prothrombotic conditions. In all, 102 IBD patients (51 with ulcerative colitis and 51 with Crohn's disease) with no history of thrombosis and 204 matched normal subjects were enrolled. DNA specimens were evaluated by PCR and restriction fragment length polymorphism for factor V Leiden, methylene tetrahydrofolate reductase (MTHFR) and prothrombin gene mutations. In IBD patients and matched controls the observed allele frequencies were similar, being 1.5% and 1.2% for factor V Leiden gene mutation, 1.1% and 0.7% for prothrombin gene mutation, and 45.1% and 47.4% for MTHFR gene mutation, respectively. These rates also were not significantly different when patients were analyzed according to age and sex distribution, diagnosis, and extension and clinical type of disease. In conclusion, our study shows no association between IBD and the most frequent hereditary prothrombotic conditions. Other factors should be evaluated in order to understand the mechanisms underlying the thrombotic risk of IBD.

Age-related clinical severity at diagnosis in 1705 patients with ulcerative colitis: a study by GISC (Italian Colon-Rectum Study Group)

Clinical-endoscopic parameters of UC presentation were studied in 1705 out-patients, observed consecutively in 17 Italian gastroenterology centers (males 60.2%; average age at diagnosis 38.5 +/- 16.4 years), and were subdivided arbitrarily into quartile age groups at diagnosis (0-25, 26-35, 36-50, >50). A significantly greater prevalence in males, increasing with age, was shown at diagnosis (P = 0.0002), which seems to correlate with the condition of being an ex-smoker, most frequently found in males. The greater frequency of exsmokers could also, in part, justify the second peak of incidence in old age. Greater colitis extent, greater clinical activity, and greater use of steroids as the first therapeutic step are shown to prevail among younger patients and among women (P = 0.02 and P = 0.019, respectively). The same is observed for symptoms mainly representing clinical severity such as diarrhea, fever, and weight loss (P = 0.004; P = 0.006; P = 0.009, respectively). This study confirms the UC risk factor represented by the condition of being an ex-smoker and shows a greater severity of illness on diagnosis in younger patients.

The natural history of ulcerative proctitis: a multicenter, retrospective study. Gruppo di Studio per le Malattie Infiammatorie Intestinali (GSMII)

OBJECTIVE

The aim of this study was to evaluate the clinical features and the long term evolution of patients with a well defined initial diagnosis of ulcerative proctitis.

METHODS

Patients with an original diagnosis of ulcerative proctitis who had been seen at any of 13 institutions from 1989 to 1994 were identified. Data on disease onset and subsequent evolution were recorded. In addition, 575 patients with more extensive disease, treated in the same centers, were used as controls.

RESULTS

A total of 341 patients satisfied the inclusion criteria. The percentage of smokers in these patients was slightly lower than in controls; no differences were found in the other clinical/demographic variables evaluated. A total of 273 patients entered long term follow-up (mean, 52 months). Proximal extension of the disease occurred in 74 of them (27.1%). The cumulative rate of proximal extension and of extension beyond the splenic flexure was 20% and 4% at 5 yr and 54% and 10% at 10 yr, respectively. The risk of proximal extension was higher in nonsmokers, in patients with >3 relapses/yr, and in patients needing systemic steroid or immunosuppressive treatment. Refractory disease was confirmed as an independent prognostic factor at multivariate analysis.

CONCLUSIONS

Proximal extension of ulcerative proctitis is frequent and may occur even late after the original diagnosis. However, the risk of extension beyond the splenic flexure appears to be quite low. Smoking seems to be a protective factor against proximal extension, whereas refractoriness is a risk factor for proximal extension of the disease.

No evidence of a major locus for benign familial infantile convulsions on chromosome 19q12-q13.1

PURPOSE

A locus for benign familial convulsions (BFICs) has been recently mapped on chromosome 19q12-13.1 by studying five families of Italian descent. The main goal of this study was to investigate the role of this locus in a set of seven newly identified families with at least three affected cases.

METHODS

Five polymorphic microsatellite markers covering the BFIC locus on chromosome 19q have been typed, and parametric linkage analysis has been performed to analyze the segregation of the BFIC locus within our families.

RESULTS

Cumulative 2-point lod scores and multipoint analysis showed no evidence of linkage between chromosome 19 markers and the BFIC phenotype. The analysis of family-specific 2-point lod scores and haplotypes, however, indicated the presence of linkage to chromosome 19q in a single family, suggesting genetic heterogeneity within our family sample.

CONCLUSIONS

Our study demonstrates that the previously reported BFIC locus on chromosome 19q12-13.1 is not a major locus for BFICs. We suggest that genetic heterogeneity may have generated our discordant linkage findings, as it was reported in benign familial neonatal convulsions, a related idiopathic mendelian syndrome.

Functional and ethnic association of allele 2 of the interleukin-1 receptor antagonist gene in ulcerative colitis

BACKGROUND & AIMS

The role of the interleukin (IL)-1 receptor antagonist (IL-1ra) in predisposing an individual to inflammatory bowel disease (IBD) is controversial. This study aimed to determine the association between intron 2 IL-1ra polymorphism and IBD by performing a multiethnic case-control study and to assess its functional significance.

METHODS

A total of 236 patients with ulcerative colitis (UC), 196 patients with Crohn's disease (CD), and 338 ethnically matched control patients treated at LAC-USC and Cedars-Sinai Medical Centers and the University of Milan Medical Center were genotyped for a variable length polymorphism in intron 2 of the IL-1ra gene (IL-1RN). Total IL-1ra protein production rates in peripheral blood mononuclear cells (PBMCs) were correlated with carriage of allele 2 of the IL-1RN gene (IL-1RN*2).

RESULTS

In the LAC-USC group, UC patients (n = 60) had an increased frequency of at least 1 copy of IL-1RN*2 compared with controls (n = 129) (70% vs. 33%; P < 0.01; odds ratio [OR], 4.7). The frequency of IL-1RN*2 carriage in the Cedars-Sinai group was 59% in UC, 45% in CD, and 42% in controls (P < 0.01; OR, 2.0). A significant difference was observed only in the Jewish subgroup (P = 0.003; OR, 5.0). The association was not detected in UC or CD patients treated at the University of Milan. The ORs of 4.7 and 5.0 appear to be the highest reported in any UC population for any genetic markers. Further, carriage of IL-1RN*2 was associated with decreased production of total IL-1ra protein in cultured PBMCs from both UC patients and controls.

CONCLUSIONS

These results provide further evidence that IL-1ra is important in the predisposition to UC, there may be genetic or pathogenetic heterogeneity between different ethnic groups, and UC and CD are genetically distinct diseases.

The role of individual SH2 domains in mediating association of phospholipase C-gamma1 with the activated EGF receptor

The two SH2 (Src homology domain 2) domains present in phospholipase C-gamma1 (PLC-gamma1) were assayed for their capacities to recognize the five autophosphorylation sites in the epidermal growth factor receptor. Plasmon resonance and immunological techniques were employed to measure interactions between SH2 fusion proteins and phosphotyrosine-containing peptides. The N-SH2 domain recognized peptides in the order of pY1173 > pY992 > pY1068 > pY1148 >> pY1086, while the C-SH2 domain recognized peptides in the order of pY992 > pY1068 > pY1148 >> pY1086 and pY1173. The major autophosphorylation site, pY1173, was recognized only by the N-SH2 domain. Contributions of the N-SH2 and C-SH2 domains to the association of the intact PLC-gamma1 molecule with the activated epidermal growth factor (EGF) receptor were assessed in vivo. Loss of function mutants of each SH2 domain were produced in a full-length epitope-tagged PLC-gamma1. After expression of the mutants, cells were treated with EGF and association of exogenous PLC-gamma1 with EGF receptors was measured. In this context the N-SH2 is the primary contributor to PLC-gamma1 association with the EGF receptor. The combined results suggest an association mechanism involving the N-SH2 domain and the pY1173 autophosphorylation site as a primary event and the C-SH2 domain and the pY992 autophosphorylation site as a secondary event.

[The topical therapy of ulcerative colitis. A multicenter study with beclomethasone dipropionate foam]

BACKGROUND AND AIMS

The use of steroids was recently extended to the various forms of ulcerative rectocolitis by the introduction of topical formulations, above all steroids with an hepatic "first pass" devoid of systemic interference. The aim of this study was to evaluate the efficacy and tolerability of Beclomethasone dipropionate (BDP) in a rectal foam formulation, in the treatment of patients suffering from ulcerative colitis.

METHODS

The experimental protocol took the form of a 28-day open prospective trial using BDP rectal foam in patients suffering from ulcerative colitis. Endoscopic, histological, clinical and tolerability parameters were evaluated. The centres taking part in the trial collected data for 60 cases out of a total of 80 patients enrolled in the study, of both sexes and aged between 20 and 81 years old, suffering from proctosigmoiditis (46.7%) and ulcerative rectocolitis (53.3%).

RESULTS

Endoscopic parameters showed an improvement after 28 days of treatment in 74.5% of patients; a clinical improvement was achieved in 65.2% of cases. In percentage terms of the mean value of all the improved parameters, histological parameters were altered in 56.9% of patients. With regard to tolerability 82% of patients judged the treatment to be good/excellent.

CONCLUSIONS

In conclusion, in line with recent reports regarding other pharmaceutical forms of BDP, including the use of rectal foam, these data confirm the efficacy and tolerability of this molecule and emphasise the validity of its use in the treatment of ulcerative colitis and proctosigmoiditis.

Physiological requirement for both SH2 domains for phospholipase C-gamma1 function and interaction with platelet-derived growth factor receptors

Two approaches have been utilized to investigate the role of individual SH2 domains in growth factor activation of phospholipase C-gamma1 (PLC-gamma1). Surface plasmon resonance analysis indicates that the individual N-SH2 and C-SH2 domains are able to specifically recognize a phosphotyrosine-containing peptide corresponding to Tyr 1021 of the platelet-derived growth factor (PDGF) beta receptor. To assess SH2 function in the context of the full-length PLC-gamma1 molecule as well as within the intact cell, PLC-gamma1 SH2 domain mutants, disabled by site-directed mutagenesis of the N-SH2 and/or C-SH2 domain(s), were expressed in Plcg1(-/-) fibroblasts. Under equilibrium incubation conditions (4 degrees C, 40 min), the N-SH2 domain, but not the C-SH2 domain, was sufficient to mediate significant PLC-gamma1 association with the activated PDGF receptor and PLC-gamma1 tyrosine phosphorylation. When both SH2 domains in PLC-gamma1 were disabled, the double mutant did not associate with activated PDGF receptors and was not tyrosine phosphorylated. However, no single SH2 mutant was able to mediate growth factor activation of Ca2+ mobilization or inositol 1,4,5-trisphosphate (IP3) formation. Subsequent kinetic experiments demonstrated that each single SH2 domain mutant was significantly impaired in its capacity to mediate rapid association with activated PDGF receptors and become tyrosine phosphorylated. Hence, when assayed under physiological conditions necessary to achieve a rapid biological response (Ca2+ mobilization and IP3 formation), both SH2 domains of PLC-gamma1 are essential to growth factor responsiveness.

Chronic unexplained hypertransaminasemia may be caused by occult celiac disease

In a subset of patients attending liver units, a chronic increase in serum transaminases may remain of undetermined cause despite thorough investigations. On the other hand, elevated levels of serum transaminases have been reported in about 40% of adult celiac patients. To evaluate the prevalence of subclinical celiac disease in patients with chronic unexplained hypertransaminasemia in comparison with that in the general population (0.5%), 140 consecutive patients with chronic increases of serum transaminases levels of unknown cause were tested for antigliadin and antiendomysium IgA antibodies. All patients with positive antibody tests were offered upper gastrointestinal endoscopy with distal duodenal biopsy. Thirteen patients (9.3%, 95% confidence interval 5. 0-15.4) had positive antigliadin and antiendomysium antibodies. The prevalence of antibodies was 17% in women and 5.4% in men (8/47 vs. 5/93 respectively; relative risk 3.2, 95% confidence interval 1.1-9. 1). Distal duodenal biopsy performed in all but one of the patients showed mild villous atrophy with increased intraepithelial lymphocytes in three cases, subtotal villous atrophy in six, and total villous atrophy in three. The prevalence of celiac disease in the patient group was significantly higher than that in the general population (P <.001) with a relative risk of 18.6 (95% confidence interval 11.1-31.2). On the basis of the present findings, screening for celiac disease is an important tool in the initial diagnostic work-up of patients with chronic unexplained hypertransaminasemia.

Serum von Willebrand factor levels in patients with inflammatory bowel disease are related to systemic inflammation

BACKGROUND

Increased levels of circulating von Willebrand factor (vWF) have been found in patients with inflammatory bowel disease (IBD); this increase may reflect either endothelial damage or systemic inflammation. Our aim was to evaluate serum vWF levels in patients with IBD and their correlation with clinical and biochemical disease activity.

METHODS

We evaluated serum vWF levels in 32 patients with ulcerative colitis (UC) (10 active with increased acute-phase reactants (APR), 6 active with normal APR, 16 in remission), 27 with Crohn disease (CD) (10 active, 12 quiescent, and 5 quiescent with increased APR), and 31 healthy controls.

RESULTS

Mean levels of vWF were 100.1 (standard deviation (s), 51.4) in IBD and 89.9 (s, 36.9) in controls (P = 0.33). Only five (8.47%) patients (three with active UC, one with active CD, and one with inactive CD but increased APR) showed circulating vWF levels higher than the upper limit of normal (150), compared with 1 (3.2%) of controls (P = 0.32). Among CD patients vWF levels were 80.0+/-25.4 in patients with quiescent disease and normal APR, 123.3+/-63.4 in patients with active disease (P = 0.04 versus inactive with normal APR), and 135.8+/-90.0 in patients with quiescent disease and increased APR (P = 0.059 versus inactive with normal APR). Among UC patients vWF levels were 82.7+/-35.6 in patients with quiescent disease and normal APR and 125.1+/-54.2 in those with active disease and increased APR (P = 0.002). Overall, mean vWF levels were significantly higher in patients with increased APR than in patients with normal APR (P = 0.0005) and controls (P = 0.009).

CONCLUSIONS

Our data show slight but significant increases in serum vWF levels in patients with IBD, which are correlated with signs of systemic inflammation.