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C Cellier

Publications and source records attributed to C Cellier.

At least 19 recordsLinked to original sources
PubMed2000

Refractory sprue, coeliac disease, and enteropathy-associated T-cell lymphoma. French Coeliac Disease Study Group.

BACKGROUND: Adult refractory sprue is a poorly defined disorder. We did a multicentre national study of patients with refractory sprue to characterise their clinical and pathological profile and outcome, and to assess the frequency and prognostic significance of phenotypic and molecular abnormalities in the intraepithelial T-cell population. METHODS: Patients with severe symptomatic villous atrophy mimicking coeliac disease but refractory to a strict gluten-free diet, and with no initial evidence of overt lymphoma, were diagnosed at gastrointestinal referral centres between 1974 and 1998. Fixed and/or frozen duodenojejunal biopsy samples were reanalysed and immunostained with CD3 and CD8 monoclonal antibodies to find out the phenotype of intraepithelial lymphocytes (IEL). TCRgamma gene rearrangements were assessed on frozen biopsy samples by multiplex fluorescent PCR. FINDINGS: There were 21 patients with refractory sprue and 20 controls with coeliacs disease. 16 (84%) of 19 assessed patients had an aberrant intraepithelial lymphoid intestinal population expressing intracytoplasmic CD3 but not surface CD8. Clonal intestinal TCRgamma gene rearrangements were found in 13 (76%) of 17 patients assessed; four (out of 12 assessed) had clonal dissemination to the blood. The 16 patients with an aberrant phenotype all had uncontrolled malabsorption; three subsequently developed overt T-cell lymphoma, and eight died. The three (16%) patients without aberrant clonal IEL made a complete clinical and histological recovery with steroid therapy plus a gluten-free diet. INTERPRETATION: An immunophenotypically aberrant clonal intraepithelial T-cell population (similar to that of most cases of enteropathy-associated T-cell lymphoma) can be found in up to 75% of patients with refractory coeliac sprue; its identification by simple diagnostic techniques represents a marker of poor outcome (including occurrence of overt T-cell lymphoma). We suggest that refractory sprue associated with an aberrant clonal IEL may be the missing link between coeliac disease and T-cell lymphoma and may be classified as cryptic enteropathy-associated T-cell lymphoma.

Adult↗
PubMed2000

Severe osteopenia in symptom-free adults with a childhood diagnosis of coeliac disease.

The frequency of osteopenia in symptom-free adults diagnosed with coeliac disease during childhood and who resumed a normal diet during adolescence is unknown. Severe osteopenia (a bone mineral density below two standard deviations of the mean) was found in up to a third of symptom-free young adults on a normal diet. These patients should not be thought to be disease-free but should receive long-term follow-up and most of them should be advised to resume a gluten-free diet.

Adolescent↗
PubMed2000

Selective expansion of intraepithelial lymphocytes expressing the HLA-E-specific natural killer receptor CD94 in celiac disease.

BACKGROUND & AIMS: Celiac disease is a gluten-induced enteropathy characterized by the presence of gliadin-specific CD4(+) T cells in the lamina propria and by a prominent intraepithelial T-cell infiltration of unknown mechanism. The aim of this study was to characterize the subset(s) of intraepithelial lymphocytes (IELs) expanding during active celiac disease to provide insights into the mechanisms involved in their expansion. METHODS: Flow-cytometric analysis of isolated IELs and/or immunohistochemical staining of frozen sections were performed in 51 celiac patients and 50 controls with a panel of monoclonal antibodies against T-cell and natural killer (NK) receptors. In addition, in vitro studies were performed to identify candidate stimuli for NK receptor expression. RESULTS: In normal intestine, different proportions of IELs, which were mainly T cells, expressed the NK receptors CD94/NKG2, NKR-P1A, KIR2D/3D, NKp46, Pen5, or CD56. During the active phase of celiac disease, the frequency of CD94(+) IELs, which were mostly alphabeta T cells, was conspicuously increased over controls. In contrast, the expression of other NK markers was not modified. Furthermore, expression of CD94 could be selectively induced in vitro by T-cell receptor activation and/or interleukin 15, a cytokine produced by intestinal epithelial cells. CONCLUSIONS: The gut epithelium favors the development of T cells that express NK receptors. In active celiac disease, there is a specific and selective increase of IELs expressing CD94, the HLA-E-specific NK receptor that may be related to T-cell receptor activation and/or interleukin 15 secretion.

Adult↗
PubMed2000

Association of a duodenal follicular lymphoma and hereditary nonpolyposis colorectal cancer.

Hereditary nonpolyposis colorectal cancer (HNPCC) is an inherited predisposition to colorectal and endometrial cancers caused by germline mutation of mismatch repair genes, with hMLH1 and hMSH2 underlying the majority of the cases. Although lymphoid tumors are the most common tumors in mouse models for HNPCC, lymphomas are almost never encountered in patients who have HNPCC, except in rare families with germline homozygous deletion of hMLH1. We report the case of a 53-year-old man who had a history of colon cancers related to constitutional hMLH1 mutation and who was diagnosed as having a duodenal follicular lymphoma This diagnosis was supported by IgH-BCL2 rearrangement and BCL2 immunoreactivity in tumor cells. The association of both of these possibly related rare diseases has never been reported. To clarify this relationship, we searched for hMLH1 expression and mismatch repair deficiency in the duodenal lymphoma. hMLH1 immunostaining was positive in lymphoid tumor cells, and no microsatellite instability was detected. In agreement with mouse models for HNPCC, these results suggest the involvement of alternative mechanisms to complete mismatch repair deficiency for lymphomagenesis in HNPCC syndrome.

Adaptor Proteins, Signal Transducing↗
PubMed2000

Distinction between coeliac disease and refractory sprue: a simple immunohistochemical method.

AIMS: We recently showed that refractory sprue is distinct from coeliac disease, the former being characterized by abnormal intraepithelial T-lymphocytes expressing a cytoplasmic CD3 chain (CD3c), lacking CD3 and CD8 surface expression, and showing TCRgamma gene rearrangements. To take advantage of the abnormal phenotype of CD3c + CD8 - intraepithelial lymphocytes (IEL) in refractory sprue we developed a simple method to distinguish coeliac disease from refractory sprue. METHODS AND RESULTS: Comparative immunohistochemical studies using anti-CD3 and anti-CD8 antibodies were applied on paraffin-embedded and frozen biopsy specimens in refractory sprue (n = 6), coeliac disease (n = 10), healthy controls (n = 5) and suspected refractory sprue (n = 6). Comparable results were obtained on fixed and frozen biopsy specimens. In four of the six patients with suspected refractory sprue, abnormal CD3c + CD8 - IEL and TCRgamma gene rearrangements were found, as in refractory sprue; the remaining two patients had normal (CD3 + CD8 +) IEL and no TCRgamma gene rearrangements. Both patients had coeliac disease, as one failed to comply with a gluten-free diet, while the other was a slow responder. CONCLUSION: This simplified immunostaining method using anti-CD3 and anti-CD8 antibodies on paraffin sections can distinguish active coeliac disease from refractory sprue and should prove useful in clinical practice.

Adult↗
PubMed2000

Biliary varices on endoscopic ultrasonography: clinical presentation and outcome.

BACKGROUND AND STUDY AIMS: Bile duct varices are not a well-recognized feature of portal venous obstruction. The aim of the present study was to describe the clinical and endosonographic features of biliary involvement in patients with extrahepatic portal venous obstruction (EPVO). PATIENTS AND METHODS: A retrospective study was conducted of the clinical features, outcome, and endosonographic findings (using Olympus EUM-3 or EUM-20 probes) in 21 patients with EPVO and endosonographic features of biliary varices. Biliary varices were defined as multiple, large, serpiginous, anechoic vascular channels in and/or surrounding the extrahepatic biliary tracts. RESULTS: Biliary varices have not previously been visible using conventional imaging methods (computed tomography and ultrasonography). They were identified using EUS in the wall of the common bile duct in 16 patients (76%), surrounding the common bile duct (CBD) in 11 patients (52%), and in the gallbladder in nine (43%). The varices were the cause of obstructive jaundice in three of the 21 patients (14%), but only when they were in the wall of the CBD. Two of these patients were treated using portosystemic shunting, and the other received a biliary endoprosthesis. The EUS examination also provided evidence of unrecognized pancreatic or biliary tumors in three other patients with EPVO of undetermined origin. CONCLUSIONS: EUS can serve to diagnose biliary varices in patients with EPVO and jaundice. Although biliary varices are mainly asymptomatic, they may cause obstructive jaundice when they are located in the wall of the CBD. EUS can also detect unrecognized malignant tumors in patients with EPVO of undetermined origin.

Adult↗
PubMed2000

Prospective multicenter study comparing a standard reusable sphincterotome with a disposable triple-lumen sphincterotome.

BACKGROUND: Few data are available on the comparative performance of different types of sphincterotome. The aim of this study was to compare the efficacy of endoscopic sphincterotomy performed with either a reusable, single-lumen sphincterotome or a disposable triple-lumen instrument. METHODS: Seventy-seven consecutive adults requiring endoscopic sphincterotomy were prospectively and randomly assigned treatment with either a standard reusable single-lumen sphincterotome (group A, n = 38) or a disposable triple-lumen sphincterotome with a guidewire (group B, n = 39). The success rate, complications, and cost of the procedure per patient were compared. RESULTS: Deep cannulation was successful in 87% of cases in each group and sphincterotomy was achieved in 76% and 84% of cases in group A and B, respectively (NS). In the endoscopists' opinion the two instruments performed almost equally well. Twelve procedure-related complications occurred: 5 (all hemorrhages) in group A and 7 (1 hemorrhage, 4 cases of pancreatitis and 2 of cholangitis) in group B (NS). Eight reusable sphincterotomes were used with a cost of $61 per patient, compared with 39 disposable sphincterotomes with a cost of $241 per patient (p = 0.02). CONCLUSIONS: A standard reusable sphincterotome is satisfactory for most endoscopic sphincterotomies, and yields a substantial cost savings without compromising the success or safety of the procedure.

Aged↗
PubMed2000

Right colonic involvement is associated with severe forms of ischemic colitis and occurs frequently in patients with chronic renal failure requiring hemodialysis.

OBJECTIVE: The aim of this study was to identify factors associated with severe outcome in patients with ischemic colitis. METHODS: The files of 60 consecutive inpatients (34 women, 26 men, mean age 67 yr) with ischemic colitis were reviewed. The following data were analyzed: age, sex, smoking, medications, history of cardiovascular disease, metabolic disease, chronic renal failure and hemodialysis, the time elapsed between the first symptoms and the diagnosis, and the site and extension of their colonic involvement. Patients were divided into two groups according to outcome: those with severe disease, including those who died from ischemic colitis (n = 3) or who required surgical resection (n = 21); and those with mild forms of colitis who were treated successfully without surgery (n = 36). The two groups were compared by means of univariate and multivariate analysis to identify factors associated with unfavorable outcomes. Only patients who had a complete examination of the colon (n = 51) were entered into the statistical analysis. RESULTS: By univariate analysis, chronic renal failure (p = 0.03), hemodialysis (p = 0.01), short delay between symptoms and diagnosis (p = 0.01), and right colonic involvement (p = 0.002) were significantly more common in the patients with severe colitis. By logistic regression, right colonic involvement was the only factor independently associated with severity (p = 0.01). Right-sided lesions were present in 82% of patients on dialysis but in only 26% of patients not on dialysis (p = 0.0005). CONCLUSIONS: Right colonic involvement is associated with severe forms of ischemic colitis and occurs frequently in patients with chronic renal failure requiring hemodialysis.

Adult↗
PubMed2000

Metastatic jejunal VIPoma: beneficial effect of combination therapy with interferon-alpha and 5-fluorouracil.

The VIPoma syndrome is rare. It is usually caused by a neuroendocrine tumor located in the pancreas. Somatostatin analogs and interferon-a can be helpful in the symptomatic control of the disease, but the efficacy of chemotherapy in metastatic disease is limited. We report the case of a 32-yr-old patient who had a primary intestinal VIPoma with peritoneal carcinomatosis and hepatic metastases. Somatostatin analogs and conventional chemotherapy regimens were not effective on VIPoma syndrome and tumor progression. The combination of 5- fluorouracil and interferon-alpha was associated with a major clinical improvement and tumor regression. Further investigations should evaluate the place of such a combination as a first line treatment for patients with metastatic neuroendocrine tumors.

Adult↗
PubMed2000

Outcome after surgical resection of intraductal papillary and mucinous tumors of the pancreas.

OBJECTIVE: Treatment of intraductal papillary and mucinous tumors of pancreas (IPMT) usually requires surgery. The objective of this study was to evaluate the risk of recurrence in patients after surgery according to the histological nature of the neoplasm and the type of surgery. METHODS: The outcome of 45 patients who underwent partial pancreatectomy (n = 35) or total pancreatectomy (n = 10) for IPMT was studied according to the nature of the neoplasm (invasive carcinoma or noninvasive neoplasm), type of surgery (partial or total pancreatectomy), and lymph nodes status. RESULTS: The overall 3-yr actuarial survival rate was 83%. Death occurred in seven of 20 (35%) patients with invasive carcinoma and in one of 26 (4%) patients with noninvasive tumors (p<0.05). There were two recurrences in the seven patients with noninvasive neoplasm who underwent partial pancreatectomy with involved resection margins, and none in the 13 patients with disease-free margins. In patients with invasive carcinoma, there was one recurrence after total pancreatectomy, six after partial pancreatectomy with disease-free margins and six after partial pancreatectomy with involved margins. In patients with invasive carcinoma, total pancreatectomy and the absence of lymph nodes involvement were independently associated with a low risk of recurrence. CONCLUSIONS: IPMT may be managed as follows: 1) in patients with noninvasive neoplasms, partial pancreatic resection should be guided by frozen section examination until disease-free margins are obtained; and 2) in patients with invasive carcinoma, total pancreatectomy seems most likely to cure the patient, but should be discussed according to the general status and the age.

Actuarial Analysis↗
PubMed2000

Endosonographic features predictive of benign and malignant gastrointestinal stromal cell tumours.

BACKGROUND/AIM: Some endoscopic ultrasonographic (EUS) features have been reported to be suggestive of malignancy in gastrointestinal stromal cell tumours (SCTs). The aim of this study was to assess the predictive value of these features for malignancy. METHODS: A total of 56 histologically proven cases of SCT studied by EUS between 1989 and 1996 were reviewed. There were 42 gastric tumours, 12 oesophageal tumours, and two rectal tumours. The tumours were divided into two groups: (a) benign SCT, comprising benign leiomyoma (n = 34); (b) malignant or borderline SCT (n = 22), comprising leiomyosarcoma (n = 9), leiomyoblastoma (n = 9), and leiomyoma of uncertain malignant potential (n = 4). The main EUS features recorded were tumour size, ulceration, echo pattern, cystic spaces, extraluminal margins, and lymph nodes with a malignant pattern. The two groups were compared by univariate and multivariate analysis. RESULTS: Irregular extraluminal margins, cystic spaces, and lymph nodes with a malignant pattern were most predictive of malignant or borderline SCT. Pairwise combinations of the three features had a specificity and positive predictive value of 100% for malignant or borderline SCT, but a sensitivity of only 23%. The presence of at least one of these three criteria had 91% sensitivity, 88% specificity, and 83% predictive positive value. In multivariate analysis, cystic spaces and irregular margins were the only two features independently predictive of malignant potential. The features most predictive of benign SCTs were regular margins, tumour size < or = 30 mm, and a homogeneous echo pattern. When the three features were combined, histology confirmed a benign SCT in all cases. CONCLUSIONS: The combined presence of two out of three EUS features (irregular extraluminal margins, cystic spaces, and lymph nodes with a malignant pattern) had a positive predictive value of 100% for malignant or borderline gastrointestinal SCT. Tumours less than 30 mm in diameter with regular margins and a homogeneous echo pattern are usually benign.

Adult↗
PubMed2000

Molecular scanning of the human PPARa gene: association of the L162v mutation with hyperapobetalipoproteinemia.

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a member of the steroid hormone receptor super family involved in the control of cellular lipid utilization. This makes PPARalpha a candidate gene for type 2 diabetes and dyslipidemia. The aim of this study was to investigate whether genetic variation in the human PPARalpha gene can influence the risk of type 2 diabetes and dyslipidemia among French Canadians. We therefore first determined the genomic structure of human PPARalpha, and then designed intronic primers to sequence the coding region and the exon-intron boundaries of the gene in 12 patients with type 2 diabetes and in 2 nondiabetic subjects. Sequence analysis revealed the presence of a L162V missense mutation in exon 5 of one diabetic patient. Leucine 162 is contained within the DNA binding domain of the human PPARalpha gene, and is conserved among humans, mice, rats, and guinea pigs. We subsequently screened a sample of 121 patients newly diagnosed with type 2 diabetes and their age and sex-matched nondiabetic controls, recruited from the Saguenay-Lac-St-Jean region of Northeastern Quebec, for the presence of the L162V mutation by a PCR-RFLP based method. There was no difference in L162 homozygote or V162 carrier frequencies between diabetics and nondiabetics. However, whether diabetic or not, carriers of the V162 allele had higher plasma apolipoprotein B levels compared to noncarriers (P 5 0.05). To further this association, we screened another sample of 193 nondiabetic subjects recruited in the greater Quebec City area. Carriers of the V162 allele compared with homozygotes of the L162 allele had significantly higher concentrations of plasma total and LDL-apolipoprotein B as well as LDL cholesterol (P </= 0.02). These results suggest an association between the PPARalpha V162 allele and the atherogenic/hyperapolipoprotein B dyslipidemia.

Animals↗