Comparison of lymphocyte isolation methods for endoscopic biopsy specimens from the colonic mucosa.

An ideal method of immune cell isolation should provide maximum cell yield without disturbing functional properties. Intestinal endoscopic biopsies, in contrast to surgical samples, allow the study of all disease stages but have the drawback of a minimum amount of tissue available, making protocol optimization mandatory. We compared for the first time two methods of separation of colonic epithelium and five methods of lamina propria cell isolation for colonic biopsy specimens (mechanical, enzymatic and organ culture protocols). Lymphocyte number, viability and phenotype (CD45+, CD103+, CD3+, CD4+, CD8+, CD19+, CD16-56+) were analyzed by flow cytometry. Neither of the two epithelial detachment protocols achieved proper epithelial separation, though the high intensity ion chelation method was more accurate. Maximum cell yield of lamina propria lymphocytes without phenotypic modification was obtained with overnight smooth enzymatic digestion. High dose collagenase incubation caused a marked decrease in CD4+ lymphocytes of the lamina propria as compared to low enzymatic method (p=0.004). Mechanical and biopsy culture are not advisable methods because of the low cell yield, and phenotypic alterations and high contamination rate, respectively.

Are positive serum-IgA-tissue-transglutaminase antibodies enough to diagnose coeliac disease without a small bowel biopsy? Post-test probability of coeliac disease.

BACKGROUND: It has been suggested that high titres of tTG are associated with elevated positive predictive values (PPV) for celiac disease. However, the PPV of a strongly positive tTG will depend on the celiac disease prevalence in the different risk groups of the disease AIMS: To assess the PPV of a strongly positive tTG for celiac disease. In addition, to calculate the post-test probability for celiac disease of a strongly positive tTG in a setting of routine clinical practice. METHODS: 145 consecutive celiac disease patients with positive tTG, and with a small bowel biopsy were included. The PPV for different cut-off points of tTG levels for the diagnosis of celiac disease was assessed. In addition, the cut-offs associated with higher PPV were used to calculate the positive likelihood ratio. A simulation in a setting of routine clinical practice was performed to calculate the post-test probability of celiac disease. RESULTS: No cut-off level was associated with a PPV of 100%. A cut-off of 80 U/mL (11.4×upper normal limit) was associated with the higher PPV value of 98.6%. In the most frequent clinical situations, which in general have a pre-test probability <10%, the post-test probability after having a strongly positive tTG was 90% or less. CONCLUSIONS: A strongly positive tTG should not be enough to diagnose celiac disease in the most frequent clinical situations, small bowel biopsy remaining as the gold standard in these cases.

Drug consumption and the risk of microscopic colitis.

BACKGROUND: Microscopic colitis is a rare disease of unknown etiology. It has been described that some drugs could cause or worsen the disease; however, the scientific evidence is limited. AIM: To investigate the possible association of chronic drug consumption with microscopic colitis. METHODS: This was a case-control study in which groups of cases were: Group 1-39 patients with collagenous colitis; Group 2-39 patients with lymphocytic colitis; and Group 3-52 patients with chronic watery diarrhea of functional characteristics. 103 subjects formed the control group. At diagnosis, a drug consumption history of at least 2-wk duration was registered. An age- and sex-adjusted logistic regression analysis was used, and the odds ratio (OR, 95% CI) was calculated. RESULTS: Drug consumption was more frequent in lymphocytic colitis than in the control group (92.3%vs 76.3%, P < 0.05). The mean daily number of drugs by person was also higher in lymphocytic colitis (3.79 +/- 0.44 vs 2.13 +/- 0.22, P= 0.04). The following associations as compared with the control group were observed: Group 1-Consumption of NSAIDs (46.2%vs 23%, OR 2.9, 1.3-6.4), selective serotonin reuptake inhibitors (SSRIs) (18%vs 1%, OR 21, 2.5-177), specifically, sertraline (15.4%vs 0%, P < 0.0005); Group 2-SSRIs (28%vs 1%, OR 37.7, 4.7-304), beta-blockers (13 vs 3%, OR 4.79, 1.04-20), statins (13%vs 3%, OR 4.6, 1.04-20), biphosphonates (8%vs 0%, P= 0.022); Group 3-SSRIs (15%vs 1%, OR 16.2, 2-135), statins (11.5%vs 3%, OR 5.4, 1.2-24). As compared with the chronic diarrhea group, a significant association with the usage of sertraline in LC (P= 0.005) and a trend for NSAIDs in CC (P= 0.057) were found. CONCLUSIONS: Drug consumption increases the risk of microscopic colitis. Some drugs might be trigger factors of colonic inflammation in predisposed hosts, and others might only worsen self-evolving microscopic colitis.

Intestinal spirochetosis and chronic watery diarrhea: clinical and histological response to treatment and long-term follow up.

BACKGROUND: The clinical significance of intestinal spirochetosis is uncertain, therefore the aim of the present paper was to assess the prevalence of histological intestinal spirochetosis in patients with and without chronic watery diarrhea and to evaluate its clinical relevance. METHODS: A prospective diagnostic work-up of intestinal spirochetosis was made on biopsy samples taken from patients with chronic watery diarrhea submitted between 1994 and 2004 (1174 colonoscopies with multiple biopsies). Three other positive cases identified from routine endoscopic biopsies also were reviewed. In addition, samples from 100 asymptomatic control patients and a random sample of another 104 colonic specimens were reviewed for intestinal spirochetosis. The diagnosis was established by light and electron microscopy. Polymerase chain reaction (PCR) amplification of the 16S ribosomal RNA and reduced nicotinamide adenine dinucleotide (NADH) oxidase genes of the intestinal spirochetes Brachyspira aalborgi and Brachyspira pilosicoli was performed on tissue biopsies of the 11 positive patients. After diagnosis, treatment with penicillin benzatine (PB) or metronidazole was offered to all symptomatic patients and they were followed for a mean of 45.4 months (range: 37-113 months). RESULTS: Eight patients with chronic watery diarrhea were positive for intestinal spirochetosis. Intestinal spirochetosis was not diagnosed in the controls. Histological resolution of the infection paralleled clinical recovery in six patients (following metronidazole treatment in three). Most patients showed mild, non-specific colonic inflammation. Invasion by the spirochetes was not demonstrated by electron microscopy. Brachyspira aalborgi and B. pilosicoli each were identified by PCR in two cases. CONCLUSIONS: Histological intestinal spirochetosis appears to be relatively uncommon in Catalonia (Spain) compared to previous reports from other countries, but was identified in patients (0.7%) with chronic watery diarrhea. Sustained clinical recovery after spontaneous or drug-induced spirochetal disappearance in these individuals suggests that intestinal spirochetosis may play a pathogenic role in chronic watery diarrhea. Treatment with metronidazole is advisable in patients with persistent symptoms.

Predisposing HLA-DQ2 and HLA-DQ8 haplotypes of coeliac disease and associated enteropathy in microscopic colitis.

OBJECTIVE: To assess the presence of both genetic and serological markers of coeliac disease in patients with microscopic colitis, and whether there was associated enteropathy. METHODS: HLA-DQ2, HLA-DQ8, serum immunoglobulin A-antiendomysial and immunoglobulin A-anti-tissue transglutaminase antibodies were investigated in 59 patients with microscopic colitis. Seventy healthy subjects acted as the control group. Endoscopic biopsies from the distal duodenum were obtained in DQ2-positive or DQ8-positive patients. Patients with histological changes compatible with gluten-sensitive enteropathy were started on a gluten-free diet. RESULTS: Seventeen of 70 (24.3%) healthy controls were DQ2-positive. Twelve of 25 (48%) patients with lymphocytic colitis (P = 0.027 versus controls), and 11 of 34 (32.3%) with collagenous colitis (P = 0.38 versus controls) were DQ2-positive. There were no differences in the frequency of DQ8-positivity. The coeliac serology was positive in one patient. Duodenal biopsies were performed in 23 DQ2-positive and/or DQ8-positive patients. None had villous atrophy (Marsh III lesion) (0%; 95% confidence interval, 0-6.1). A Marsh type I lesion was found in four patients. Three of these patients were put on a gluten-free diet with disappearance of diarrhoea. CONCLUSIONS: The results suggest that there is an association of lymphocytic colitis with HLA-DQ2 genes, which might be relevant in the pathogenesis of this disease. The association of microscopic colitis with Marsh type III coeliac disease seems to be rare, making it unnecessary to routinely screen for coeliac disease in microscopic colitis patients.

Collagenous and lymphocytic colitis. evaluation of clinical and histological features, response to treatment, and long-term follow-up.

OBJECTIVE: Data on collagenous colitis (CC) and lymphocytic colitis (LC) have been based on retrospective studies of registries of patients from multiple hospitals. Such studies may induce a selection of patients with severe forms of the disease, and conclusions about the clinical spectrum of the disease and treatment efficacy are difficult to be drawn. The aim of this study was to compare the clinical features, response to treatment, and long-term follow-up of CC and LC in a large group of patients prospectively diagnosed in a single center. METHODS: A specific program was undertaken to prospectively diagnose all patients with microscopic colitis from those referred for a full colonoscopy because of recurrent or chronic diarrhea. Detailed clinical and histological features, response to treatment, and long-term follow-up were compared in patients with confirmed CC and LC. RESULTS: Thirty-seven patients with CC and 44 with LC were included. Patients with CC were significantly younger and had a significantly longer duration of diarrhea before diagnosis than those with LC. Otherwise, clinical presentation was similar. Drug-induced disease was suspected for ticlopidine, flutamide, gold salts, and bentazepam in LC. Complete resolution of diarrhea was achieved in all patients, spontaneously occurring in nearly 20% of them. Response to salicylates (mainly, mesalazine) was significantly better in LC than in CC (86% vs 42%, p = 0.005). Cholestyramine was highly effective in patients of both groups with concomitant bile acid malabsorption. Patients with CC required prednisone more often than those with LC (30% vs 4.5%, p = 0.005). Both prednisone and budesonide controlled ileal release were highly effective in patients with CC (82% and 89% efficacy). After cessation of diarrhea, 25% of patients with LC and 30% of those with CC relapsed after a mean follow-up of around 3 yr. CONCLUSIONS: CC and LC share a similar clinical picture and have a benign course with long-term cessation of diarrhea in more than 70% of patients. Mesalazine and budesonide seem to be good options as first-line treatment in LC and CC, respectively. Cholestyramine may be a good alternative in patients with concomitant bile acid malabsorption.

[Induction therapy with interferon alfa-2a in compensated hepatitis C virus-related cirrhosis. Randomized, multicenter study]. / Terapia de inducción con interferón alfa-2a en la cirrosis por el virus de la hepatitis C compensada. Estudio multicéntrico aleatorizado.

BACKGROUND: Although standard dose interferon (IFN) is successful in only 5% of patients with compensated hepatitis C virus (HCV)-related cirrhosis, it has been suggested that this therapy might decrease the risk of complications or the incidence of hepatocellular carcinoma. Based on HCV kinetics, daily IFN may improve response rates. PATIENTS AND METHOD: Forty cirrhotic patients were randomised to receive (Group I: 19) or not (Group II: 21) treatment with IFN (4.5 MU/daily for 24 weeks, followed by 4.5 MU/48 hours for a further 24 weeks period, only if ALT was within normal values). RESULTS: Dose reduction and discontinuation for adverse events was required in 11 (58%) and 6 (31.5%) cases, respectively. End-of-treatment response was not observed in any of the 21 controls but in 4 of the 19 (21%) treated patients (p = 0.04); a sustained response was achieved in only 2 treated patients (10.5%). The 3-year probability of developing any of the following: ascites, hepatocellular carcinoma, transplantation or death was lower in Group I than in Group II (6% vs 27%; p = 0.05). CONCLUSION: Although induction IFN therapy is associated with common side effects and poor sustained response in compensated HCV-related cirrhosis, it might improve the outcome of patients at the medium-term.