Folate pathway gene alterations in patients with neural tube defects

Periconceptional folate supplementation reduces the recurrence and occurrence risk of neural tube defects (NTD) by as much as 70%, yet the protective mechanism remains unknown. Inborn errors of folate and homocysteine metabolism may be involved in the aetiology of NTDs. Previous studies have demonstrated that both homozygosity for the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene, and combined heterozygosity for the C677T and for another mutation in the same gene, the A1298C polymorphism, represent genetic risk factors for NTDs. In an attempt to identify additional folate related genes that contribute to NTD pathogenesis, we performed molecular genetic analysis of folate receptors (FRs). We identified 4 unrelated patients out of 50 with de novo insertions of pseudogene (PS)-specific mutations in exon 7 and 3'UTR of the FRalpha gene, arising by microconversion events. All of the substitutions affect the carboxy-terminal amino acid membrane tail, or the GPI anchor region of the nascent protein. Furthermore, among 150 control individuals, we also identified one infant with a gene conversion event within the FRalpha coding region. This study, though preliminary, provides the first genetic association between molecular variations of the FRalpha gene and NTDs and suggests that this gene can act as a risk factor for human NTD.     

Correlation between IgA antiendomysial antibodies and subtotal villous atrophy in dermatitis herpetiformis.

Serum IgA antiendomysial antibodies (EmA) were present in 20 (64.5%) of 31 patients with dermatitis herpetiformis (DH) on a normal diet. A significant correlation was found between these antibodies and the severity of gluten-induced jejunum damage. IgA EmA were positive in 19 (86%) of the 22 DH patients with subtotal villous atrophy, in comparison with the positivity of only one (11%) of the nine DH patients with less severe intestinal involvement (partial villous atrophy or mild abnormalities). The specificity of this test for gluten-sensitive enteropathy was 100%, these antibodies being consistently negative in biopsied disease controls showing a normal jejunal mucosa. Moreover, IgA EmA proved to be useful in monitoring the response to gluten withdrawal in DH patients, as these antibodies always disappeared in all the DH cases studied after 1 year of gluten-free diet together with the regrowth of jejunal villi. The strict relationship between IgA EmA and subtotal villous atrophy is more helpful still since the enteropathy present in DH is usually symptomless and therefore difficult to suspect.     

Natural history of portal hypertension in patients with cirrhosis

All patients with cirrhosis will eventually develop portal hypertension and esophagogastric varices. Bleeding from ruptured esophagogastric varices is the most severe complication of cirrhosis and is the cause of death in about one third of patients. The rate of development and growth of esophageal varices is poorly defined but in general seem to be related to the degree of liver dysfunction. Once varices have formed, they tend to increase in size and eventually to bleed. In unselected patients, the incidence of variceal bleeding is about 20% to 30% at 2 years. Variceal size is the single most important predictor of a first variceal bleeding episode. Several prognostic indexes based on endoscopic and clinical parameters have been developed to predict the risk of bleeding; however, their degree of accuracy is unsatisfactory. Death caused by uncontrolled bleeding occurs in about 6% to 8% of patients; the 6-week mortality rate after a variceal hemorrhage is 25% to 30%. There are no good prognostic indicators of death caused by uncontrolled bleeding or death within 6 weeks. Untreated patients surviving a variceal hemorrhage have a 1- to 2-year risk of rebleeding of about 60% and a risk of death of about 40% to 50%. The risk of bleeding is greatest in the first days after a bleeding episode and slowly declines thereafter. All patients surviving a variceal hemorrhage must be treated to prevent rebleeding. Varices can also be found in the stomach of cirrhotic patients, alone or in association with esophageal varices. Gastric varices bleed less frequently but more severely than esophageal varices. Portal hypertensive gastropathy is a common feature of cirrhosis, and its prevalence parallels the severity of portal hypertension and liver dysfunction. Portal hypertensive gastropathy can progress from mild to severe and vice-versa or even disappear completely. Acute bleeding from portal hypertensive gastropathy seems to be relatively uncommon, and less severe than bleeding from varices.     

Capsule enteroscopy in small bowel transplantation

BACKGROUND: Enteroscopy plays a key role in the post-operative monitoring of patients with small bowel transplantation for the early detection of post-transplant complications and for the assessment of the graft's integrity. Routine surveillance enteroscopies (trans-stomal terminal ileoscopy or jejunoscopy) are invasive, may be unsafe in frail patients, and only allow incomplete exploration of the transplanted graft, which may be unsatisfactory. since the distribution of the lesions is often patchy or segmental. AIMS. To evaluate the potential of capsule enteroscopy, a new, minimally invasive technique which allows complete exploration of the small bowel. in small bowel transplant recipients. METHODS: Five small bowel transplanted patients underwent capsule enteroscopy with the GIVEN endoscopy system. The results of capsule enteroscopy were compared with those of trans-stomal ileoscopy. RESULTS: Capsule enteroscopy was better tolerated than ileoscopy and good quality images of the small bowel were obtained in four patients. The terminal ileum was normal both on ileoscopy and capsule enteroscopy. Mucosal changes in segments not reached by ileoscopy were detected by capsule enteroscopy in three of four patients. CONCLUSIONS: Capsule enteroscopy is better tolerated than ileoscopy, allows complete exploration of the transplanted graft and can detect mucosal changes in segments not reached by ileoscopy.     

B1a lymphocytes in the rectal mucosa of ulcerative colitis patients

AIM:To assess B1a cell expression in the rectal mucosa of ulcerative colitis (UC) patients in comparison with healthy controls.METHODS:Rectal mucosa biopsies were collected from 15 UC patients and 17 healthy controls.CD5 + B cells were analysed by three colour flow cytometry from rectal mucosal samples after mechanical disaggregation by Medimachine.Immunohistochemical analysis of B and T lymphocytes was also performed.Correlations between,on the one hand,rectal B1a cell concentrations and,on the other,erythrocyte sedimentation rate and C-reactive protein levels and clinical,endoscopic and histological disease activity indices were evaluated.RESULTS:Rectal B-lymphocyte (CD19 + /CD45 +) rate and concentration were higher in UC patients compared with those in healthy controls (47.85% ± 3.12% vs 26.10% ± 3.40%,P=0.001 and 501 ± 91 cells/mm 2 vs 117 ± 18 cells/mm 2,P 0.001);Rectal B1a cell density (CD5 + CD19 +) was higher in UC patients than in healthy controls (85 ± 15 cells/mm 2 vs 31 ± 6.7 cells/mm 2,P=0.009).Rectal B1a cell (CD5/CD19 +) rate correlated inversely with endoscopic classification (Rs=-0.637,P 0.05).CONCLUSION:B1a lymphocytes seem to be involved in the pathogenesis of UC,however,the role they play in its early phases and in disease activity,have yet to be defined.     

Prevalence of hyperhomocysteinemia in adult gluten-sensitive enteropathy at diagnosis: role of B12, folate, and genetics.

BACKGROUND & AIMS: Hyperhomocysteinemia, a risk factor for thrombosis, recurrent miscarriages, and osteoporosis, might derive from acquired folate and vitamin B 12 deficiencies and from a C677T mutation in methylene-tetrahydrofolate reductase (MTHFR) gene. Undiagnosed gluten-sensitive enteropathy (GSE) is associated with vitamin deficiencies, osteoporosis, and recurrent miscarriages. We evaluated the prevalence and the risk factors for hyperhomocysteinemia in patients with newly diagnosed GSE. METHODS: In this prospective study performed in a tertiary care setting, 40 consecutive subjects with newly diagnosed GSE were evaluated for homocysteine, folate, and vitamin B 12 levels and for C677T polymorphism. One hundred twenty sex- and age-matched healthy control subjects were studied. Nonparametric tests and multiple regression analysis were used to evaluate the risk factors in inducing hyperhomocysteinemia in the GSE population. RESULTS: Hyperhomocysteinemia was more frequent in GSE patients than in control subjects (8/40, 20.0% vs 7/120, 5.8%) (relative risk, 3.4; 95% confidence interval, 1.3-8.9), as well as folate deficiency (17/40, 42.5% vs 10/120, 8.3%) (relative risk, 5.1; 95% confidence interval, 2.5-10.2). Multiple regression analysis showed that folate and B 12 levels were independently and inversely associated with homocysteine levels, whereas homozygosity for the MTHFR thermolabile variant was not. The prevalence of MTHFR variant in GSE population was not different from that reported in racially comparable control groups. Gluten-free diet was able to normalize folate, vitamin B 12 , and homocysteine levels. CONCLUSIONS: Hyperhomocysteinemia is frequent in newly diagnosed GSE. Vitamin deficiencies caused by malabsorption are the most important determinants of this condition. Hyperhomocysteinemia might contribute to the occurrence of common complications of undiagnosed GSE.     

Prevalence of fasting hypercalciuria associated with increased citraturia in the ambulatory evaluation of nephrolithiasis

BACKGROUND: Nephrolithiasis is a common, high costing pathology of the urinary tract. The most common urinary abnormalities are fasting hypercalciuria, hypercalciuria and hypocitraturia. This study aimed to identify the principal urinary abnormalities in our patients. METHODS: Ninety-eight patients (pts) (43 females, 55 males) with recurrent calcium nephrolithiasis underwent metabolic evaluation. In two 24-hr urine collections the following parameters were evaluated: calcium, phosphate, sodium, potassium, chloride, magnesium, citrate, oxalate, uric acid, creatinine (Cr), urea, ammonium and pH; blood measurement of calcium, phosphate, sodium, potassium, chloride, magnesium, uric acid, Cr, urea, acid-base balance ionized calcium and intact parathyroid hormone (iPTH) were also performed. A first morning voided urine sample was collected for measuring the urinary cross-links and fasting calciuria. The tubular threshold of phosphate (TmP) was calculated according to Walton and Bijovet. Metabolic evaluation was repeated in 63/98 pts after 7 days on a low calcium diet. RESULTS: The most common urinary abnormalities were fasting hypercalciuria in 51/96 pts (53.1%), hypercalciuria in 33/97 pts (34%) and hypocitraturia in 29/98 pts (29%); 24/33 pts (73%) with hypercalciuria had fasting hypercalciuria. Hypercalciuria was partially corrected on the calcium-restricted diet, while fasting hypercalciuria was not. Urine citrate levels were significantly higher in patients with fasting hypercalciuria. CONCLUSIONS: Fasting hypercalciuria was the most frequent urinary abnormality and it was not corrected with a calcium-restricted diet. In fasting hypercalciuric patients, increased bone resorption activity could be responsible for higher citraturia levels.     

Onset of inflammatory bowel diseases during combined alpha-interferon and ribavirin therapy for chronic hepatitis C: report of two cases

We report two patients who developed an inflammatory bowel disease (IBD) shortly after beginning combined alpha-interferon and ribavirin treatment for HCV-related chronic hepatitis. The previous clinical history was negative for IBD in both patients, who developed diarrhoea and rectal bleeding 10 days and 6 months, respectively, after the initiation of therapy. The history, therapeutic management and the possible causal relationships of these cases are discussed.     

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.