Metronidazole reduces intestinal inflammation and blood loss in non-steroidal anti-inflammatory drug induced enteropathy.

This study assessed the effect of metronidazole on the gastroduodenal mucosa, intestinal permeability, blood loss, and inflammation in patients on non-steroidal anti-inflammatory drugs (NSAIDs). Thirteen patients were studied before and after 2-12 weeks' treatment with metronidazole 800 mg/day, while maintaining an unchanged NSAID intake. Intestinal inflammation, as assessed by the faecal excretion of indium-111 labelled neutrophils, and blood loss, assessed with chromium-51 labelled red cells, were significantly reduced after treatment (mean (SD) 111In excretion 4.7 (4.7)% v 1.5 (1.3)% (N < 1.0%), p < 0.001, 51Cr red cells loss 2.6 (1.6) ml/day v 0.9 (0.5) ml/day (N < 1.0 ml/day), p < 0.01). Intestinal permeability assessed as the 5 hour urinary excretion ratio of 51CrEDTA/L-rhamnose did not change significantly (0.133 (0.046) v 0.154 (0.064), p > 0.1) and there were no significant changes in the endoscopic or microscopic appearances of the gastroduodenal mucosa. These results suggest that the neutrophil is the main damaging effector cell in NSAID induced enteropathy. The main neutrophil chemo-attractant in this enteropathy may be a metronidazole sensitive microbe.     

Assessment of Disease Activity in Ulcerative Colitis Using Indium-111-Labelled Leukocyte Faecal Excretion

A new method of assessing disease activity in ulcerative colitis has been developed utilizing indium-111-labelled granulocytes. Faecal ¹¹¹In excretion after intravenous administration of labelled granulocytes ranged from 1.1% to 45% of the injected dose in patients with ulcerative colitis, showing significant differences between mild, moderate, and severely active groups. There was a significant correlation between faecal ¹¹¹In excretion and a clinical index based on the Crohn's disease activity index (r = 0.79, p < 0.001) and the erythrocyte sedimentation rate (r = 0.73, p < 0.001). Quantitative faecal ¹¹¹In-labelled granulocyte excretion is an objective and specific method of assessing disease activity in ulcerative colitis.     

Outcome of restorative proctocolectomy when the diagnosis is suggestive of Crohn's disease.

Twenty of 81 patients treated by restorative proctocolectomy for presumed ulcerative colitis had some features of Crohn''s disease: 10 were classified as definite Crohn''s disease and 10 as indeterminate colitis. These pathological features were first apparent during synchronous colectomy and pouch construction in 10 of 11 cases. In the remainder, histological features of possible Crohn''s disease were first identified during rectal excision (n = 6), preliminary subtotal colectomy (n = 2), and after pouch excision (= 2). Complications were marginally more common in patients with features of possible Crohn''s disease: pelvic sepsis 30% (Crohn''s disease 30%, indeterminate colitis 30%) v 20%, fistulas 45% (Crohn''s disease 30%, indeterminate colitis 60%) v 16%; ileal stenosis 40% (Crohn''s disease 40%, indeterminate colitis 40%) v 21%, pouchitis 50% (Crohn''s disease 50%, indeterminate colitis 50%) v 26%, and small bowel obstruction 25% (Crohn''s disease 30%, indeterminate colitis 30%) v 13%. Pouch excision or a persistent proximal stoma has been necessary in six patients with possible Crohn''s disease (30%) (Crohn''s disease 3 cases 30%, indeterminate colitis 3 cases 30%) compared with nine (15%) of the remainder. Median hospital stay, however, was the same and stool frequency in those with a functioning pouch were comparable. These results show that there is a higher complication rate if there are features of Crohn''s disease but that the medium term functional results are acceptable if the pouch can be retained.     

The function in vitro of macrophages from the intestinal mucosa of patients with Crohn's disease: An association between chemotactic migration and granulomata

The chemotactic migration in vitro of intestinal macrophages and peripheral blood monocytes has been assessed in patients with Crohn's disease, ulcerative colitis, and miscellaneous intestinal diseases. In all groups, the chemotaxis of peripheral blood monocytes was similar to that of healthy subjects. Intestinal macrophages migrated similarly to autologous monocytes in patients with ulcerative colitis and in the miscellaneous group. In contrast, intestinal macrophages from patients with Crohn's disease exhibited a wide range of chemotaxis from markedly suppressed to normal. This variation was independent of drug treatment and the degree of inflammation present. However, patients in whom granulomata were not present exhibited a significant depression of chemotaxis compared with those with granulomata, with disease controls (ulcerative colitis patients), and with the miscellaneous group. Such a difference was not reflected in monocytes from autologous peripheral blood. These findings indicate the presence of local mucosal suppressive factors in some patients with Crohn's disease and could suggest that the diminished ability of macrophages to accumulate in a focus of inflammation may be an underlying mechanism for the failure to form granulomata in these patients.     

Studies on the enteropathy associated with primary hypogammaglobulinaemia.

Twelve patients with primary hypogammaglobulinaemia with diarrhoea not associated with known microbial pathogens were investigated. Histological evidence of inflammation was common in the stomach and jejunum. Moreover, eight of 10 patients undergoing colonoscopy had low grade ''microscopic colitis'' with raised intraepithelial lymphocytes and an intact crypt architecture. Five of 12 patients had small intestinal inflammation on 111indium leucocyte scintigrams and all had increased faecal excretion (normal < 1%) of 111indium (over four days), which varied in intensity from mild (faecal excretion of 111indium = 1-3%) to that comparable with moderately active (7-14.5%) Crohn''s disease. Three patients had small intestinal strictures superficially resembling Crohn''s disease. Histologically, however, these lacked characteristic diagnostic features of Crohn''s disease in two and the third patient had non-steroidal anti-inflammatory drug induced diaphragm like strictures. Six of seven who were most severely symptomatic were successfully treated with an elemental diet with rapid improvement of symptoms. The faecal excretion of 111indium was repeated in five and all improved but histologically the colitis remained unchanged. These studies show that some patients with primary hypogammaglobulinaemia have intestinal inflammation unlike that found in classic inflammatory bowel disease. Elemental diet is a useful temporary measure in the treatment of these patients.     

Incidence of inflammatory bowel disease in northern France (1988-1990).

There were no data concerning the incidence of inflammatory bowel disease (IBD) in France. The aim of this study was to investigate the incidence of Crohn''s disease and ulcerative colitis in northern France. This prospective population based study was realised through the gastroenterologists of the region Nord-Pas de Calais and the Somme Department. Each gastroenterologist referred patients consulting for the first time with clinical symptoms compatible with IBD. Data were collected by an interviewer practitioner present at the gastroenterologist''s consulting room. Two independent expert gastroenterologists assessed each case in a blind manner and made a final diagnosis of Crohn''s disease, ulcerative colitis, ulcerative proctitis, or unclassifiable chronic colitis. From 1988 to 1990, 1291 cases of IBD were recorded: 674 (52%) Crohn''s disease, 466 (36%) ulcerative colitis including 162 proctitis (35%), and 151 (12%) unclassifiable chronic colitis. The mean annual incidence was 4.9 per 100,000 for Crohn''s disease and 3.2 for ulcerative colitis. The sex ratio F/M was 1.3 for Crohn''s disease and 0.8 for ulcerative colitis. The highest age specific incidence rate for Crohn''s disease was between 20 and 29 years: 13.1 for women and 9.8 for men. The highest age specific incidence rate for ulcerative colitis was between 20 and 39 years: 5.5 for women and 6.5 for men. This first French prospective study has shown an incidence rate for Crohn''s disease comparable with that seen in north European studies but lower than that seen for ulcerative colitis. These results could be related to the different environmental factors or the genetic background of the population studied, or both.     

Serum lysozyme,serum proteins,and immunoglobulin determinations in nonspecific inflammatory bowel disease

The serum levels of lysozyme, serum electrophoresis, and serum immunoglobulins were determined prospectively in 101 patients with ulcerative colitis, ulcerative proctitis, Crohn's disease, or nonclassifiable nonspecific inflammatory bowel disease. Although the mean serum lysozyme concentration of patients with Crohn's disease (10.5±6.8 μg/ml) and ulcerative colitis (9.6±4.1 μg/ml) performed by a standardized lysoplate method was significantly greater than normal controls (6.0±1.5 μg/ml), the results did not correlate with the diagnosis nor with the degree of disease activity. Individually separated protein fractions and serum immunoglobulins also did not correlate with the serum lysozyme levels. This study indicates that measurement of the level of serum lysozyme in individual patients is not helpful in determining the cause or degree of activity of non-specific inflammatory bowel disease.     

Refractory pouchitis: does it reflect underlying Crohn's disease?

Typical ''pouchitis'' is a well recognised complication of ileal pouches in ulcerative colitis. Infrequently, a refractory pouchitis (RP) presents with certain clinical, endoscopic, and pathological features resembling Crohn''s disease and is often ascribed to misdiagnosis of the initial colitis. To test that hypothesis and to identify risk factors for RP, this study reviewed cases of presumed ulcerative colitis with ileal pouches constructed at The Mount Sinai Hospital between 1973 and 1986. Twenty four cases with RP (16 Kock pouches and eight pelvic pouches) and 21 controls were compared for eight clinical variables. The original colectomy slides from 15 RP and 18 control cases were reviewed blindly, classified into five histological categories (corresponding to definite ulcerative colitis, definite Crohn''s disease, and three indeterminate groups), and scored for 23 histological features. There were no significant clinical differences between RP and control cases except for more frequent extraintestinal manifestations (38% v 5%) and male preponderance (79% v 43%) in RP. There were also no significant differences between the distributions of RP cases and controls among the five histological categories or in the 23 histological features studied. Refractory pouchitis therefore does not seem to reflect underlying Crohn''s disease, but may be linked to immunological mechanisms that are manifested clinically as extraintestinal complications.     

Surface epithelium related activation of complement differs in Crohn's disease and ulcerative colitis.

IgG1 and activated complement are colocalised on the colonic epithelial brush border in active ulcerative colitis. To investigate whether such deposition is specific for ulcerative colitis, we examined ethanol fixed mucosal specimens from 18 patients with Crohn''s colitis and 14 with terminal ileitis by indirect two colour immunofluorescence staining. Monoclonal antibodies to the IgG subclasses and to neoepitopes of activated complement C3b and the terminal complement complex were used in combination with rabbit antiserum to C1q, C4c or cytokeratin. Granular deposition of C3b and terminal complement complex were observed at the luminal face of the surface epithelium in 10 of 18 patients with Crohn''s colitis. Specimens from eight of 14 patients with ileal involvement were intensely stained for activated complement (primarily C3b) within the surface mucus layer. No epithelial IgG, C1q or C4c deposition was observed. The results suggest that early and late phase complement activation takes place at the luminal face of the epithelium in Crohn''s disease. The absence of colocalised IgG and complement components involved in the classical activation pathway (C1q and C4c), however, suggest that other immunopathological mechanisms (the alternative pathway?) are primarily involved in Crohn''s disease in contrast with ulcerative colitis.     

Smoking in inflammatory bowel disease: Impact on disease course and insights into the aetiology of its effect

The chronic intestinal inflammation that characterises Crohn's disease and ulcerative colitis arises from a complex interplay between host genotype, the immune system, and the intestinal microbiota. In addition, environmental factors such as smoking impact on disease onset and progression. Individuals who smoke are more likely to develop Crohn's disease, and smoking is associated with recurrence after surgery and a poor response to medical therapy. Conversely, smoking appears protective against ulcerative colitis and smokers are less likely to require colectomy. The mechanism by which smoking exerts its impact on disease and the rational for the dichotomous effect in patients with Crohn's disease and ulcerative colitis is not clear. Recent evidence suggests that smoking induces alterations to both the innate and acquired immune system. In addition, smoking is associated with a distinct alteration in the intestinal microbiota both in patients with active Crohn's disease and healthy subjects.     

Increased Serum Levels of Vascular Endothelial Growth Factor in Patients with Inflammatory Bowel Disease

Background: Vascular endothelial growth factor (VEGF) is a potent angiogenic, vascular permeability-enhancing, and calcium-dependent enzyme-modulating cytokine with overexpression in various pathologic disorders, including granulomatous inflammation, tissue repair, delayed hypersensitivity reactions, rheumatoid arthritis, and tissue ischemia. The present study investigates the role of VEGF in chronic inflammatory bowel disease. Methods: Thirty-one patients with Crohn's disease, 15 patients with ulcerative colitis, and 9 healthy volunteers were studied. VEGF serum levels were measured with a solid-phase enzyme-linked immunosorbent assay. Results: Significantly increased VEGF serum levels were observed in both active Crohn's disease and active ulcerative colitis when compared with healthy controls. Patients with active Crohn's disease and active ulcerative colitis showed significantly higher VEGF serum levels than patients with quiescent disease. No difference was observed between inactive disease and healthy controls. In addition, strongly increased VEGF serum levels were found in patients with Crohn's disease with fistulas in the absence of clinical, endoscopic, histologic, and laboratory findings of disease activity. Conclusions: Significantly increased VEGF serum levels were observed in patients with active Crohn's disease and ulcerative colitis, which suggests that VEGF has an important role in chronic inflammatory bowel disease. Its possible association with fistulas has yet to be determined.     

Familial occurrence and inheritance studies in inflammatory bowel disease

A number of studies have demonstrated aggregation of cases of ulcerative colitis or Crohn's disease in families, and of cases of both diseases within the same families, suggesting that patients share a genetic background. Perhaps because of differences in the selection of patients, study design and diagnostic criteria, different patterns of occurrence of inflammatory bowel disease (IBD) have been found among relatives of patients with these disorders. In recent years, however, several studies have been carried out, aiming by epidemiological methods to reveal (1) the frequency of familial occurrence of IBD among patients with ulcerative colitis and Crohn's disease, and (2) the prevalence of IBD among 1⁰ relatives to patients with these diseases. Results from these studies show a relatively uniform pattern of family occurrence in about 10% of patients with ulcerative colitis and Crohn's disease, and a prevalence among 1⁰ relatives of about 10 times that of the background population. A twin study reported a significantly higher concordance rate for Crohn's disease than for ulcerative colitis in monozygotic twins. By use of complex segregation analyses in 3 different studies, a very similar model of inheritance was found to fit for ulcerative colitis, namely a major dominant or additive gene with a low penetrance. For Crohn's disease the best-fitting model was a major recessive gene, with a high penetrance. This difference strongly supports the concept of ulcerative colitis and Crohn's disease as two separate disease entities. The occurrence of both diseases within the same families in certain members of the affected families is difficult to explain. The search for distinct associations of HLA genes with inflammatory bowel disease has shown a positive correlation between DR2 and ulcerative colitis and a negative association with DR4 and DRw6, compared with ethnically matched controls. In contrast, in Crohn's disease a positive association with the combination of DR1 and DQw5 alleles was revealed, thus indicating genetically different disease susceptibility for the two disorders. In general, however, no consistent pattern has been revealed from studies of association of HLA-A or -B antigens or blood group and serum protein markers. In two French families with several members affected with Crohn's disease no evidence for an HLA haplotype association could be revealed. Possible inherited markers of ulcerative colitis or Crohn's disease have been sought but without convincing success. Increased intestinal permeability, presence of anticolon antibodies and presence of antineutrophil leukocyte antibodies have been proposed, but not proved. Thorough studies are now needed of multimember families with disease for linkage studies to identify loci which contribute to increased liability. Such studies are in progress in different centres.     

Microalbuminuria correlates with intestinal histopathological grading in patients with inflammatory bowel disease.

It has previously been shown that microalbuminuria is a useful disease activity marker for inflammatory bowel disease (IBD). Microalbuminuria correlates strongly with the markers of clinical and laboratory disease activity such as erythrocyte sedimentation rate (ESR), and C reactive protein (CRP). The aim of this study was to discover if microalbuminuria accurately reflects the intestinal inflammation by correlating it with intestinal inflammation using a standard histopathological grading system in patients with ulcerative colitis and Crohn's colitis. Forty two patients with IBD who had undergone endoscopic examination of the entire colon for the assessment of severity and extent of the disease (Crohn's colitis (n = 21), ulcerative colitis (n = 21)) were recruited to the study. Patients with small bowel Crohn's disease were not studied. Twenty four patients had left sided colonic disease and 18 patients had extensive colonic disease. Each patient's colonic biopsy specimens were scored blindly by a histopathologist and a composite score was compiled on the basis of the severity of changes in the enterocytes and crypts and the cellularity of the lamina propria. A clinical disease activity was obtained using the simple index of Harvey and Bradshaw. Microalbuminuria was measured in all patients by an immunoturbiditimetric method. ESR and CRP were also measured, as indicators of acute phase response in the same patients. It was found that patients with active IBD had higher concentrations of microalbuminuria compared with those patients in remission (median 222 micrograms/min (range 40-686 micrograms/min) v median 96 micrograms/min (range 30-376 micrograms/min); p < 0.001)). Significantly higher concentrations of microalbuminuria were also detected in patients with extensive colonic IBD compared with those patients with left sided disease (median 297 micrograms/min (range 132-686 micrograms/min) v median 101 micrograms/min (range 30-433 micrograms/min); p < 0.001)). A strong positive correlation was seen between microalbuminuria and intestinal histopathological score in IBD patient groups with left sided colitis (r = 0.77; p < 0.001) and extensive disease (r = 0.71; p < 0.01). The standard histopathological grading system correlated with the clinical disease activity (r = 0.64; p < 0.005) and CRP (r = 0.62; p < 0.02), however, it did not correlate with ESR. In conclusion, the strong correlation of microalbuminuria with a standard intestinal histopathological grading system suggests that microalbuminuria accurately reflects the severity of colonic inflammation in patients with Crohn's colitis and ulcerative colitis.     

Adhesion molecules in inflammatory bowel disease.

The ability of leucocytes to adhere to endothelium is essential for leucocyte migration into inflammatory sites. Some of these adhesion molecules are released from the cell surface and can be detected in serum. The soluble adhesion molecules intercellular adhesion molecule 1 (ICAM-1), E selectin, and vascular cell adhesion molecule 1 (VCAM-1) were studied in the serum of patients with Crohn's disease, ulcerative colitis, and healthy controls. A second blood sample was taken from patients with active disease after one month of treatment and a third two months after remission was achieved. Tissue expression of the same adhesion molecules was studied by immunohistology. Circulating VCAM-1 concentrations were significantly higher in patients with active ulcerative colitis (n = 11, median = 165 U/ml) compared with patients with inactive ulcerative colitis (n = 10, median = 117 U/ml, p < 0.005), active Crohn's disease (n = 12, median = 124 U/ml, p < 0.02), and controls (n = 90, median = 50 U/ml, p < 0.0001). Within each disease group there were no significant differences in E selectin or ICAM-1 concentrations between the active and inactive states, however, patients with active Crohn's disease had significantly higher ICAM-1 concentrations (n = 12, median = 273 ng/ml) than controls (n = 28, median = 168, p < 0.003). VCAM-1 concentrations fell significantly from pretreatment values to remission in active ulcerative colitis (p < 0.01). In Crohn's disease there was a significant fall in ICAM-1 both during treatment (p < 0.01) and two months after remission (p < 0.02). Vascular expression of ICAM-1 occurred more often and was more intense in inflamed tissue sections from patients with ulcerative colitis and Crohn's disease than from controls. Vascular labelling with antibody to E selectin also occurred more often in patients with active inflammatory bowel disease. In conclusion, increased circulating concentrations of selected adhesion molecules are associated with inflammatory bowel disease. There is also evidence of local upregulation, particularly of ICAM-1. Differential expression of adhesion molecules in tissue may play a part in the initiation of leucocyte migration and local inflammation; the function of circulating adhesion molecules is unknown, but may play a physiological part in blocking adhesion.     

Reversibility of Increased Intestinal Permeability to 51Cr-EDTA in Patients with Gastrointestinal Inflammatory Diseases

Intestinal permeability in adults with inflammatory gastrointestinal diseases was investigated by measuring the 24-h urinary excretion of orally administered 51Cr-EDTA. Eighty controls along with 100 patients with Crohn's disease, 46 patients with ulcerative colitis, 20 patients with gluten-sensitive enteropathy, and 18 patients with other diseases were studied. In controls, the median 24-h excretion was 1.34%/24 h of the oral dose. Patients with Crohn's disease (median 2.96%/24 h), ulcerative colitis (median 2.12%/24 h), and untreated gluten-sensitive enteropathy (median 3.56%/24 h) had significantly elevated urinary excretion of the probe compared to controls (p less than 0.0001). Increased 24-h urinary excretion of 51Cr-EDTA had a high association with intestinal inflammation (p less than 0.0001). Test specificity and sensitivity were 96% and 57%, respectively. A positive test has a 96% probability of correctly diagnosing the presence of intestinal inflammation, whereas a negative test has a 50% probability of predicting the absence of disease.     

Anti-lactoferrin antibodies and other types of ANCA in ulcerative colitis,primary sclerosing cholangitis,and Crohn's disease.

Fifty two serum samples from patients with Crohn''s disease, 24 from patients with ulcerative colitis, and 12 from patients with primary sclerosing cholangitis were analysed for the presence of anti-neutrophil cytoplasm antibodies (ANCA) of IgG and IgA class by means of enzyme linked immunosorbent assays using lactoferrin, myeloperoxidase, and antigen extracted from azurophil granules, ''alpha antigen'' (that is, an antigen preparation containing proteinase 3) as substrates. A high frequency of positive tests for IgG anti-lactoferrin antibodies was found in sera from patients with ulcerative colitis (50%) and primary sclerosing cholangitis (50%). In Crohn''s disease only 4 of 52 (8%) sera had anti-lactoferrin antibodies--in all four instances the sera belonged to patients with disease involving the colon. All patients with sclerosing cholangitis and positive tests for anti-lactoferrin had ulcerative colitis. Low levels of IgG antibodies against myeloperoxidase or alpha antigen were also found occasionally in sera from patients with ulcerative colitis and primary sclerosing cholangitis. IgA antibodies directed against lactoferrin and alpha antigen (but not myeloperoxidase) were seen in all three conditions.     

Increased interleukin 8 expression in the colon mucosa of patients with inflammatory bowel disease.

To test whether there is a difference in the expression of interleukin 8 (IL8) between Crohn's disease and ulcerative colitis and to determine the main site of its synthesis this study analysed IL8 in mucosal biopsy specimens of patients with Crohn's disease and ulcerative colitis by enzyme linked immunosorbent assay (ELISA) and by in situ hybridisation. IL8 was measured by ELISA in 38 normal control patients, eight inflammatory control patients, 55 Crohn's disease biopsy specimens (26 patients), and 67 ulcerative colitis biopsy specimens (35 patients). IL8 mRNA was determined in samples by in situ hybridisation using a specific IL8 RNA probe. IL8 protein was significantly increased in macroscopically inflamed specimens of Crohn's disease (median 118 pg/specimen, p < 0.0001), ulcerative colitis (median 140 pg/specimen, p < 0.001), and inflammatory controls (median 30 pg/specimen, p = 0.010) compared with normal controls (median 4 pg/specimen). IL8 was also increased in uninflamed specimens of Crohn's disease (median 46 pg/specimen, p < 0.001) but not of ulcerative colitis patients (median 9 pg/specimen, p = 0.3). IL8 protein in the mucosa correlated significantly with macroscopic inflammation in Crohn's disease (r = 0.47, p < 0.001) and in ulcerative colitis (r = 0.60, p < 0.001). IL8 mRNA was detected by in situ hybridisation in 31 of 55 biopsy specimens (56%) of Crohn's disease patients, in 38 of 67 specimens of ulcerative colitis patients (57%), in five of eight inflammatory controls (63%) and in five of 38 normal controls (13%). Mucosal IL8 mRNA expression correlated with mucosal IL8 protein (r = 0.46, p < 0.001). IL8 mRNA was only detected in inflammatory cells of the interstitium but not in mucosal epithelial cells. IL8 is produced mainly in the lamina propria of the colon in inflammatory bowel disease and correlates with mucosal inflammation.     

Prevalence of inflammatory bowel disease in family members of Jewish Crohn's disease patients in Israel

A familial study of 189 Jewish Crohn's disease patients was conducted in order to evaluate the risk for inflammatory bowel disease (IBD) in relatives of the patients and to try to understand better the genetic component in the etiology of the disease among Jews. One hundred fifty-seven patients filled out questionnaires that were verified by personal interviews. In 10 families (6.6%), a first-degree relative of the propositus was found to have IBD, seven Crohn's disease and three ulcerative colitis. Among first-degree relatives, siblings were more frequently affected: of 400, five had Crohn's disease and one ulcerative colitis. Among 304 parents, two had Crohn's disease and two ulcerative colitis, while none of the propositi's children had IBD. The prevalence of first-degree relatives with Crohn's disease was similar in the 98 and 45 families of Ashkenazi and non-Ashkenazi origin: 5.1% and 4.4%, respectively. The risk for siblings of the probands to be affected were also similar in the two groups: 1.5% and 1.8%; while parents of the probands were affected only in the group of Ashkenazi Jews.