A70 Viromes of two migratory birds as support for identifying the influence of molecular biology and bioinformatics settings

Thanks to high-throughput sequencing (HTS) and dedicated bioinformatics tools, it is possible to study all viruses present in a sample with an unprecedented detection of viral diversity. Applied to wildlife and humans, HTS becomes a powerful means to understand viral emerging infectious diseases. BLAST searches to find remote homolog sequences after an assembly of shotgun-generated sequences are often used to analyze virome datasets. However, this process might be biased by molecular biology approaches (use of whole genome/transcriptome amplification) and bioinformatics assembly that can induce chimeric sequences formation. Our objective was to identify confounding factors (molecular biology and bioinformatics) that can bias virome composition. Hence, we studied the viromes from cloacal swab samples of two migratory birds. Viral DNA and RNA were extracted using three different methods (easymag^®, phenol, and trizol), followed by whole genome amplification (WGA)/WTA amplifications, before Illumina MiSeq sequencing. After trimming and assembly, sequences underwent BLAST (BLASTn and BLASTx). At the end of the first BLAST (n/x), some portions of sequences were uncovered and unassigned. We, then, implemented a novel recursive split-resubmit python program that searched for homologs of > 50 base pairs (bp), uncovering parts for a better exploitation of the datasets. Thirty-eight known viral families were detected in our samples. Circoviridae, Parvoviridae, and Microviridae were found in the majority of the results from easymag^® and Phenol extracted samples, while trizol samples resulted in a majority of Picornaviridae and Coronaviridae. These results show that the viromes are of different composition depending on extraction methods. Most of the viral sequences were predominantly identified at the blastx step reflecting a high level of divergence with known viral sequences. Compared to a unique BLAST search, our resubmission pipeline allowed the assignment of up to 23 per cent of the viral sequences. Most of these sequences belonged to taxa already observed at the first blast step and few viral sequences of different families were detected. Knowing the complementarities between extraction methods and a better identification of viral sequences using our pipeline, the next step will be to get a precise position of each viral genomic segment in phylogenetic distance-based tree that will give a more accurate representation of viral diversity.

[Dengue virus infection in neotropical forest mammals: incidental hosts or potential reservoirs?]

The arboviral disease with the highest human incidence in South America is dengue fever. In French Guiana, where all four dengue serotypes, i.e., DENV-1, DENV-2, DENV-3 and DENV-4, are present, the disease is endemic with epidemic outbreaks. Though previous serological studies have suggested a sylvatic cycle, involvement of wild mammals in the dengue cycle in the neotropics has never been confirmed. The purpose of this study was to search for the presence of DENV in wild animals captured at two different sites between 2001 and 2007. About 10,000 trap/nights were performed leading to the capture of 464 non-flying mammals (rodents and marsupials). In addition, mistnests placed in the same zone yielded 152 bats. Reverse transcription-polymerase chain reaction amplification to detect infection by any of the four dengue serotypes demonstrated viral RNA in the livers and/or sera of 92 captured animals. Sequence analysis of amplification products revealed that the DENV-1, DENV-3 and DENV-4 serotypes were distinct from those circulating in humans at the same periods. Analysis for DENV-2 showed that some strains were divergent from concurrent human strains but that others were identical. The latter finding suggests that wild neotropical mammals living in periurban area can be infected by dengue virus strains circulating in humans. However, further investigation will be needed to determine if neotropical mammals are incidental hosts or potential reservoirs of dengue virus.

Surgical resection plus chemotherapy versus chemotherapy alone: comparison of two strategies to treat diffuse large B-cell gastric lymphoma

BACKGROUND

The usefulness of chemotherapy to treat gastric diffuse large B-cell lymphomas (DLBCL) is well known. Whether or not chemotherapy should be performed as the only treatment or after surgical resection is debated. The aim of this study was to compare two strategies: surgical resection plus chemotherapy versus chemotherapy alone.

PATIENTS AND METHODS

Between January 1988 and December 1996, 58 patients included in the trials promoted by the Groupe d'Etude des Lymphomes de l'Adulte (GELA) (LNH-87 and LNH-93) received chemotherapy and 48 included in the protocol of the Groupe d'Etude des Lymphomes Digestifs (GELD) underwent surgical resection followed by chemotherapy. They all presented with localized DLBCL (stage IE and IIE according to the Ann Arbor classification). From the GELA group, seven patients received additional radiotherapy. Gastrectomy was total in 27 of the 48 patients in the GELD group. In both groups chemotherapy included anthracyclin and alkylating agents. Chemotherapy was more intensive in the GELA group than in the GELD group.

RESULTS

In the GELA and the GELD groups, distribution according to sex ratio, age (>60 or < or = 60 years), ECOG performance status (> or = 2 or <2) and staging (IE or IIE) was similar. Univariate analysis comparing prognostic factors in both groups showed significant differences: serum lactate dehydrogenase level above normal (28.6% versus 2.4%, P = 0.001), tumor size >10 cm (28.6% versus 12.5%, P = 0.04), patients with International Prognostic Index (IPI) >1 (21.4% versus 11.1%, P = 0.168) and 5-year survival (79% versus 90%, P = 0.03). Multivariate analysis of prognostic factors with a Cox model showed that IPI was the only independent prognostic factor (odds ratio 3, P = 0.03). Consequently, patients with IPI 0-1 were selected for comparison between the GELA group (44 patients) and the GELD group (40 patients). There was no significant difference between the two groups. Median follow-up was 59 months (range 3-128). Estimates of 5-year survival rates and event-free survival rates were 90.5% versus 91.1% (P = 0.303) and 85.9% versus 91.6% (P = 0.187), respectively. In the GELA group, seven of 44 patients died: five from a lymphoma-unrelated cause and two from tumor progression. In the GELD group, four of 40 patients died: two of unrelated causes and two from tumor progression.

CONCLUSIONS

This study shows that in localized gastric DLBCL with IPI 0-1, a similar 5-year survival rate (>90%) is to be expected with either surgery plus chemotherapy or chemotherapy alone.

Genetic diversity and phylogenetic analysis of human immunodeficiency virus type 1 subtypes circulating in French Guiana

We investigated the characterization of different HIV-1 subtypes present in French Guiana by use of three different methods. Serological methods were used for the initial screening, which were then confirmed by the heteroduplex mobility assay (HMA). The V3 env region was subsequently sequenced for phylogenetic analysis, to confirm the subtype of the samples, and to assign a subtype to samples that gave results that were difficult to interpret or discordant by serology or HMA. A total of 221 HIV-1 seropositive samples were typed; 110 of them were confirmed by HMA and 16 were sequenced. Of the 221 samples tested 210 patients (95%) were found to be infected with subtype B, 10 (4.5%) were infected with subtype A, and one patient was infected with subtype F. Phylogenetic analysis demonstrated that the strains from French Guiana were closely related to the subtype A and B subtypes, and that one strain was closely related to an F subtype (100% bootstrap value). Four strains from French Guiana clustered in the subtype A (99% bootstrap value) and the other strains were associated with subtype B (100% bootstrap value). The geographic position of French Guiana suggested that HIV-1 was probably introduced into the country via several routes, and thus the pattern of the HIV-1 epidemic might evolve in the near future.

Predictive factors for regression of gastric MALT lymphoma after anti-Helicobacter pylori treatment

BACKGROUND AND AIMS

Discrepant remission rates (41-100%) have been reported for patients with localised low grade gastric mucosa associated lymphoid tissue (MALT) lymphoma after eradication of Helicobacter pylori. The aim of this study was to explain these discrepancies and to determine the predictive factors of gastric lymphoma regression after anti- H pylori treatment.

PATIENTS AND METHODS

Forty six consecutive patients with localised gastric MALT lymphoma (Ann Arbor stages I(E) and II(E)) were prospectively enrolled. All had gastric endoscopic ultrasonography and H pylori status assessment (histology, culture, polymerase chain reaction, and serology). After anti-H pylori treatment, patients were re-examined every four months.

RESULTS

Histological regression of the lymphoma was complete in 19/44 patients (43%) (two lost to follow up). Median follow up time for these 19 responders was 35 months (range 10-47). No regression was noted in the 10 H pylori negative patients. Among the 34 H pylori positive patients, the H pylori eradication rate was 100%; complete regression rate of the lymphoma increased from 56% (19/34) to 79% (19/24) when there was no nodal involvement at endoscopic ultrasonography. There was a significant difference between the response of the lymphoma restricted to the mucosa and other more deep seated lesions (p<0.006). However, using multivariate analysis, the only predictive factor of regression was the absence of nodal involvement (p<0.0001).

CONCLUSION

In H pylori positive patients with localised gastric MALT lymphoma, carefully evaluated and treated without any lymph node involvement assessed by endoscopic ultrasonography, complete remission of lymphoma was reached in 79% of cases.

Histological, immunohistochemical, ultrastructural and biochemical study of human gastric composite tumor: expression of the serotonin-2B receptor by the neuroendocrine component

We report a case of a human gastric composite tumor occurring seven years after a partial gastrectomy for a low grade B cell MALT lymphoma. Histological examination of the tumor revealed two intimately intermingled components: 1. A moderately to poorly differentiated tubulo-acinar adenocarcinoma with signet-ring cells; and 2. Isolated or clustered small neuroendocrine cells without atypia expressing chromogranin A, somatostatin and/or glucagon, serotonin (5-HT) and, the 5-HT2B receptors. In addition to immunohistochemical detection, the presence of 5-HT2B receptors was shown pharmacologically through [125I]-DOI binding. Since 5-HT2B receptors have been demonstrated to have autocrine functions and, mitogenic and transforming properties, these results suggest a role of 5-HT in neuroendocrine malignant transformation. On the other hand, the expression of somatostatin and the detection by reverse transcriptase polymerase chain reaction (RT-PCR) of somatostatin receptor subtypes 2, 3, and 5, which have been shown to be involved in tumor regression, might account for the long evolution of this case (> 5 yr). This case illustrates the importance of local humoral modulation in tumor growth. Moreover, ultrastructural results favor a unique origin of the tumor cells from one amphicrine cell type.

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.

The clinicopathological features of extensive small intestinal CD4 T cell infiltration

METHODS

Four patients with clinicopathological features suggesting a new distinct entity defining extensive small intestinal CD4 T cell infiltration were observed.

RESULTS

All four patients presented with chronic diarrhoea, malabsorption, and weight loss. Biopsy specimens of the small intestine disclosed extensive and diffuse infiltration of the lamina propria by pleomorphic small T lymphocytes, which were positive for CD3, CD4, CD5, and the beta chain of T cell receptor in all three cases studied and negative for CD103 in all three cases studied. It is notable that, in all invaded areas, the infiltrating cells showed no histological change throughout the whole evolution. In three patients, lymphocyte proliferation was monoclonal and there was extraintestinal involvement. In one patient, lymphoproliferation was oligoclonal and confined to the small intestine. In all four patients, there was no evidence of coeliac disease. Although none of the four patients responded to single or multiple drug chemotherapy, median survival was five years.

CONCLUSION

Extensive small intestinal CD4 T cell infiltration is a rare entity, distinct from coeliac disease and associated with prolonged survival.

Granulocytic sarcoma of the jejunum: a rare cause of small bowel obstruction

We report the case of a 40-yr-old man presenting with symptoms of small bowel obstruction. Small bowel x-rays revealed a stricture of the mid-jejunum. Push enteroscopy found a polypoid mass at 1 meter of the ligament of Treitz. Histopathological examination of the biopsy and surgical specimens showed a diffuse infiltrate of the mucosa made of medium to large cells, which were stained on immunohistochemistry by the leucocyte marker CD45 and the histiocyte/monocyte marker CD68 but were negative for the B and T cell markers. Cytological examination of the ascitic fluid revealed many myelobasts with cytoplasmic Auer rods and positive myeloperoxidase staining. There was no evidence of blood or bone marrow involvement suggestive of acute leukemia or myeloproliferative disorders. These findings were consistent with the diagnosis of preleukemic granulocytic sarcoma (or chloroma). Chemotherapy led to complete remission, but 21 months later the patient developed an acute myeloid leukemia. He died from aspergillus pneumonitis, 10 months after bone marrow allograft. Preleukemic granulocytic sarcoma of the small bowel is a rare condition and its diagnosis is usually not easy, requiring histochemical or immunohistochemical studies. Most cases have progressed to acute myeloid leukemia.

Primary intestinal gamma-delta T-cell lymphoma with evidence of Epstein-Barr virus

AIMS

Primary intestinal T-cell lymphomas account for about 5% of all primary gastrointestinal lymphomas and are mostly associated with coeliac disease. They usually express the CD3-associated T-cell receptor alpha/beta heterodimer and HML1, and some are related with Epstein-Barr virus (EBV). As far as we know, the present report describes the first case of primary gamma-delta (gamma delta) EBV-associated intestinal T-cell lymphoma without enteropathy. Only hepatosplenic, nasal and cutaneous gamma delta T-cell lymphomas have previously been described.

METHODS AND RESULTS

Our case concerned a 43-year-old man with no history of coeliac disease, who presented with multifocal small bowel involvement showing high grade T-cell lymphoma with medium sized and large pleomorphic cells and a small pleomorphic T-cell component. Angioinvasion and angiocentricity were occasionally present. Immunohistochemical studies of lymphoma cells showed a T-cell gamma delta phenotype (CD3+, CD2+, TCR delta 1+, V delta 2+ and beta F1-) without expression of CD4, CD8, CD5, or HML1. Most tumour cells were positive for the cytotoxic granular proteins TiA1 and granzyme B. Rearrangement of the TCR gamma chain gene was demonstrated by polymerase chain reaction and in-situ hybridization with EBER probes revealed strong nuclear positivity in virtually all neoplastic cells.

CONCLUSION

We described the first case of primary intestinal gamma delta T-cell lymphoma without enteropathy in which EBV might fulfil a pathogenic role.

[Association of a low-grade MALT lymphoma and a slightly differentiated adenocarcinoma of the stomach]

The development of synchronous gastric adenocarcinoma and primary gastric lymphoma is rare. We report a case of low grade B-cell lymphoma of mucosa associated lymphoid tissue intermingled with a gastric adenocarcinoma and without Helicobacter pylori infection. This observation leads to discuss the pathogenesis of these tumors and the role of Helicobacter pylori infection in the development of gastric lymphoma and carcinoma.

[Severe colitis in mucoviscidosis]

We report the association of severe indeterminate colitis with cystic fibrosis in a 21 year old woman, with mild pulmonary involvement, and without digestive or pancreatic symptoms or pancreatic enzyme preparation. Ten cases of inflammatory bowel disease associated with a cystic fibrosis have been reported. Most fit with the diagnostic criteria of Crohn's disease. Although this case was compatible with this diagnosis, we have retained the diagnosis of "severe indeterminate colitis" because of the lack of specific histological features of Crohn's disease. The association between inflammatory bowel disease and cystic fibrosis is probably not fortuitous, although the pathophysiological link between the two diseases is unknown.

Multiple lymphomatous polyposis of the gastrointestinal tract: prospective clinicopathologic study of 31 cases. Groupe D'étude des Lymphomes Digestifs

BACKGROUND & AIMS

Multiple lymphomatous polyposis (MLP) is an uncommon type of gastrointestinal lymphoma. The aim of this study was to analyze the clinicopathologic features and outcome of a large series of patients.

METHODS

From 1984 to 1995, 31 patients were enrolled prospectively. Exhaustive staging and immunohistochemical analysis were performed. The first 10 patients were treated with cyclophosphamide-vincristine-prednisolone (COP) and the subsequent 21 with doxorubicin-teniposide-cyclophosphamide-prednisolone (AVmCP). Eleven patients were treated with high-dose radiochemotherapy and stem cell autotransplantation because of partial response or relapse.

RESULTS

Advanced age and multiple polyps involving several gastrointestinal segments characterized initial clinical presentation. The typical tumor cell phenotype (pan-B+, CD5+, and CD10-) along with Bcl-1 rearrangement indicated that MLP is the gastrointestinal counterpart of mantle cell lymphoma. After COP treatment, only 3 patients achieved partial remissions, whereas 80% of patients after AVmCP treatment achieved complete or good partial remission. High-dose radiochemotherapy changed partial into complete remission in 80% of cases. None of the initial 10 patients survived for 3 years, but the expected 5-year survival rate was 59% in patients receiving the anthracycline-containing regimen (P < 0.0001).

CONCLUSIONS

MLP is a distinct entity among gastrointestinal lymphomas. An anthracycline-containing multidrug regimen and high-dose radiochemotherapy supported by autotransplantation seem to improve its poor prognosis.

Interordinal mammalian relationships: evidence for paenungulate monophyly is provided by complete mitochondrial 12S rRNA sequences

The complete mitochondrial 12S rRNA sequences of 5 placental mammals belonging to the 3 orders Sirenia, Proboscidea, and Hyracoidea are reported together with phylogenetic analyses (distance and parsimony) of a total of 51 mammalian orthologues. This 12S rRNA database now includes the 2 extant proboscideans (the African and Asiatic elephants Loxodonta africana and Elephas maximus), 2 of the 3 extant sirenian genera (the sea cow Dugong dugon and the West Indian manatee Trichechus manatus), and 2 of the 3 extant hyracoid genera (the rock and tree hyraxes Procavia capensis and Dendrohyrax dorsalis). The monophyly of the 3 orders Sirenia, Proboscidea, and Hyracoidea is supported by all kinds of analysis. There are 23 and 3 diagnostic subsitutions shared by the 2 proboscideans and the 2 hyracoids, respectively, but none by the 2 sirenians. The 2 proboscideans exhibit the fastest rates of 12S rRNA evolution among the 11 placental orders studied. Based on various taxonomic sampling methods among eutherian orders and marsupial outgroups, the most strongly supported clade in our comparisons clusters together the 3 orders Sirenia, Proboscidea, and Hyracoidea in the superorder Paenungulata. Within paenungulates, the grouping of sirenians and proboscideans within the mirorder Tethytheria is observed. This branching pattern is supported by all analyses by high bootstrap percentages (BPs) and decay indices. When only one species is selected per order or suborder, the taxonomic sampling leads to a relative variation in bootstrap support of 53% for Tethytheria (BPs ranging from 44 to 93%) and 7% for Paernungulata (92-99%). When each order or suborder is represented by two species, this relative variation decreased to 10% for Tethytheria (78-87%) and 3% for Paenungulata (96-99%). Two nearly exclusive synapomorphies for paenungulates are identified in the form of one transitional compensatory change, but none were detected for tethytherians. Such a robust and reliable resolution of the paenungulate node implies a long history of the common ancestors, allowing time for synapomorphies to accumulate. This observation suggests a Late Cretaceous/Early Paleocene origin for the Paenungulata.

Ileal pouch/anal anastomosis for Crohn's disease

BACKGROUND

Patients with Crohn's disease (CD) are not commonly considered as candidates for ileal pouch/anal anastomosis (IPAA). This approach has been avoided because of the poor results observed, retrospectively, in patients with an initial diagnosis of ulcerative colitis who were found to have CD on examination of the resected specimen. However, in 1985, we decided to investigate an alternative to coloproctectomy with definitive end-ileostomy by a prospective study of IPAA for selected patients with CD.

METHODS

Between 1985 and 1992, 31 patients with CD, but with no evidence of anoperineal or small-bowel disease, were recruited to our study. They comprised 15 men and 16 women whose mean age was 36 years (SD 14; range 16-72). All CD patients underwent IPAA. The short-term and long-term functional results of this procedure were compared with those of 71 ulcerative colitis patients who also underwent IPAA during the same period in our unit. Mean follow-up was 59 (SD 25) months.

FINDINGS

No significant differences were observed between patients with CD and ulcerative colitis in the postoperative complication rate. Of the 31 CD patients, six (19%) experienced specific complications 9 months to 6 years after surgery: three had pouch-perineal fistulas, which required pouch excision in two cases; one had a pouch-vaginal fistula that was treated by gracilis muscle interposition; and one had an extrasphincteric abscess, which was treated surgically. Two patients (6%), one of whom was treated for an extrasphincteric abscess, experienced CD recurrence on the reservoir, and were treated successfully with azathioprine. At 5-year follow-up, there were no significant differences between patients with CD and ulcerative colitis in stool frequency (5.0 [2.0] vs 4.7 [1.4] per day; p=0.68), continence, gas/stool discrimination, leak or need for protective pads, and sexual activity.

INTERPRETATION

Our results show that in selected cases of CD without anoperineal or small-bowel manifestations, IPPA can be recommended as an alternative to coloprotectomy with definitive end-ileostomy, when rectal resection is essential.

Multiple lymphomatous polyposis of the gastrointestinal tract. An extensive histopathologic and immunohistochemical study of 12 cases

BACKGROUND

Multiple lymphomatous polyposis (LP) is a rare entity, characterized by multiple polypoid tumors involving several segments of the gastrointestinal tract.

METHODS

In this large retrospective series of 12 patients with LP, histologic and immunohistochemical features were investigated from patients with multiple biopsy samples from each site (500 gastrointestinal biopsies). Immunohistochemistry was performed on paraffin embedded biopsies from 12 patients and on frozen tissue biopsies from 8 patients, for each of whom at least two different anatomic sites were studied.

RESULTS

Histologic features always were characterized by nodules located in mucosa and submucosa composed of lymphomatous, small cleaved cells. B-cell phenotype of the neoplastic cells was the same phenotype as adult mantle-zone cells or fetal follicle cells (frequent coexpression of surface IgM and surface IgD, and weak expression of CD5, CD35+, CDw32+, and CD23-). Tested cases expressed bcl-2. Five to 20% of LP cells were positive for the monoclonal antibody Ki-67. Five patients died within 5-32 months after diagnosis. Frequent extradigestive sites were also identified. There were two unique findings: five cases with digestive tract lymphoepithelial lesions (LEL), and one secondary transformation to large B-cell malignant lymphoma.

CONCLUSIONS

To the authors' knowledge, this is the largest series so far of LP studied with immunohistochemistry on frozen sections. Mantle-cell B cell phenotype of the nodular monotonous, small cleaved cells is confirmed. This entity may be classified as mantle-cell lymphoma with a similar aggressive clinical course, and treated as a high grade B-cell lymphoma. The authors know of no such LEL that has been reported previously, and secondary transformation has been described only briefly in one case.

TH mRNA over-expression in rats with chronic excitotoxic striatal lesions

Twenty weeks after ibotenic acid lesions of the striatum, the amount of tyrosine hydroxylase (TH) in this structure was markedly increased. This was accompanied by a 3-fold increase in TH mRNA levels in the ipsilateral subtantia nigra (SN). Striatal levels of dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) were markedly reduced. In the nucleus accumbens, spared by the lesion, DA neurotransmission was also altered, as evidenced by a reduction of DA and DOPAC, but no increase in TH could be detected. TH mRNA levels were moderately enhanced in the ventral tegmental area (VTA). Thus, lesioning in the striatum induces TH gene activation in both SN and VTA neurones, not strictly related to DA function at the terminal level.

Regulation of tyrosine hydroxylase gene expression in mesencephalic dopamine neurons: effect of imipramine treatment

The effects of a chronic imipramine treatment on the mesoamygdaloid pathway of rats were examined. Using semiquantitative immunocytochemical techniques, it was observed that the level of TH mRNA was decreased in the ventral tegmental area (VTA). In contrast, the TH protein was increased in both the VTA and amygdala. The TH activity was decreased in the amygdala when assessed under normal conditions but increased after a preincubation to phosphorylate the enzyme, suggesting a lowering of the protein-specific activity in the terminals. These results show that TH protein turnover in the mesoamygdaloid neurons can be reduced by chronic imipramine treatments, thereby producing an accumulation of inactive TH protein in the neurons while also decreasing TH gene activity in the cell bodies.

Multiple lymphomatous polyposis of the gastrointestinal tract. An extensive histopathologic and immunohistochemical study of 12 cases

BACKGROUND

Multiple lymphomatous polyposis (LP) is a rare entity, characterized by multiple polypoid tumors involving several segments of the gastrointestinal tract.

METHODS

In this large retrospective series of 12 patients with LP, histologic and immunohistochemical features were investigated from patients with multiple biopsy samples from each site (500 gastrointestinal biopsies). Immunohistochemistry was performed on paraffin embedded biopsies from 12 patients and on frozen tissue biopsies from 8 patients, for each of whom at least two different anatomic sites were studied.

RESULTS

Histologic features always were characterized by nodules located in mucosa and submucosa composed of lymphomatous, small cleaved cells. B-cell phenotype of the neoplastic cells was the same phenotype as adult mantle-zone cells or fetal follicle cells (frequent coexpression of surface IgM and surface IgD, and weak expression of CD5, CD35+, CDw32+, and CD23-). Tested cases expressed bcl-2. Five to 20% of LP cells were positive for the monoclonal antibody Ki-67. Five patients died within 5-32 months after diagnosis. Frequent extradigestive sites were also identified. There were two unique findings: five cases with digestive tract lymphoepithelial lesions (LEL), and one secondary transformation to large B-cell malignant lymphoma.

CONCLUSIONS

To the authors' knowledge, this is the largest series so far of LP studied with immunohistochemistry on frozen sections. Mantle-cell B cell phenotype of the nodular monotonous, small cleaved cells is confirmed. This entity may be classified as mantle-cell lymphoma with a similar aggressive clinical course, and treated as a high grade B-cell lymphoma. The authors know of no such LEL that has been reported previously, and secondary transformation has been described only briefly in one case.

Colonoscopy of acute colitis. A safe and reliable tool for assessment of severity

Complications that might lead to surgery in severe attacks of ulcerative colitis have been found to be correlated with the depth of colonic ulcerations as measured by pathological examination of colectomy specimens. In order to evaluate the value of colonoscopy for the assessment of colonic ulcerations, we have reviewed the clinical, biological, colonoscopic, and anatomical findings in 85 consecutive patients with attacks of ulcerative colitis involving at least the rectosigmoid and part of the descending colon, seen in our center between 1981 and 1989. All had colonoscopy performed by a senior endoscopist at entry. Extensive deep colonic ulcerations were diagnosed in 46 of them, and moderate endoscopic colitis in 39. No complication related to colonoscopy occurred except for one colonic dilatation. Forty-three of the 46 patients with severe endoscopic colitis were operated upon; 38 of them failed to improve with high-dose corticosteroids and five had a toxic megacolon. Extensive ulcerations reaching at least the circular muscle layer were found at pathological examination of colectomy specimen in 42 of the 43 patients. Conversely, 30 of 39 patients with moderate endoscopic colitis went into clinical remission with medical treatment, and only nine patients needed further surgery because of medical treatment failure. Six of these nine patients underwent another colonoscopy prior to colectomy, and all six showed features of severe endoscopic colitis. Deep ulcerations reaching the circular muscle layer were found at pathological examination in five of these six patients and in one additional patient whose colonoscopy had been performed 21 days before colectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Extensive small intestinal T-cell lymphoma of low-grade malignancy associated with a new chromosomal translocation

BACKGROUND

Primary T-cell lymphoma of the small intestine is rare, and most cases have proved rapidly fatal.

METHODS

We describe a case of lymphoma involving the small intestine uniformly and extensively in a 28-year-old man on initial examination seen with long-standing diarrhea, malabsorption, and recurrent episodes of intestinal obstruction. Clinical remission was obtained with pentostatin (2'-deoxycoformycin, supplied by Professor Catovsky, London UK) after the patient had failed to improve under conventional chemotherapy. Tumor specimens as well as mesenteric lymph node, liver, and bone marrow specimens were studied with conventional pathology and immunochemistry. Additionally, mesenteric lymph nodes and peripheral blood cells were studied for T-cell receptor (TCR) gene rearrangement and karyotype.

RESULTS

Lymphoma cells were small T-lymphocytes with irregular pleomorphic nuclei, bearing the CD3, CD4 and TCR alpha-beta phenotype. Peripheral-blood cytology and bone marrow biopsy were normal. Southern blot analysis of the TCR beta-chain gene revealed the same monoclonal rearrangement in the mesenteric lymph nodes and peripheral blood lymphocytes. An as yet undescribed t(4;16)(q26;p13) translocation, involving the region where the interleukin-2 (IL-2) gene has been mapped, was present in the mesenteric lymph nodes and peripheral blood lymphocytes.

CONCLUSION

We believe this is the first description of an extensive, small intestinal lymphoma of low-grade malignancy made up of monoclonal T-cells with a TCR alpha-beta and helper/inducer phenotype, associated with a novel chromosomal translocation.

Extensive small intestinal T-cell lymphoma of low-grade malignancy associated with a new chromosomal translocation

BACKGROUND

Primary T-cell lymphoma of the small intestine is rare, and most cases have proved rapidly fatal.

METHODS

We describe a case of lymphoma involving the small intestine uniformly and extensively in a 28-year-old man on initial examination seen with long-standing diarrhea, malabsorption, and recurrent episodes of intestinal obstruction. Clinical remission was obtained with pentostatin (2'-deoxycoformycin, supplied by Professor Catovsky, London UK) after the patient had failed to improve under conventional chemotherapy. Tumor specimens as well as mesenteric lymph node, liver, and bone marrow specimens were studied with conventional pathology and immunochemistry. Additionally, mesenteric lymph nodes and peripheral blood cells were studied for T-cell receptor (TCR) gene rearrangement and karyotype.

RESULTS

Lymphoma cells were small T-lymphocytes with irregular pleomorphic nuclei, bearing the CD3, CD4 and TCR alpha-beta phenotype. Peripheral-blood cytology and bone marrow biopsy were normal. Southern blot analysis of the TCR beta-chain gene revealed the same monoclonal rearrangement in the mesenteric lymph nodes and peripheral blood lymphocytes. An as yet undescribed t(4;16)(q26;p13) translocation, involving the region where the interleukin-2 (IL-2) gene has been mapped, was present in the mesenteric lymph nodes and peripheral blood lymphocytes.

CONCLUSION

We believe this is the first description of an extensive, small intestinal lymphoma of low-grade malignancy made up of monoclonal T-cells with a TCR alpha-beta and helper/inducer phenotype, associated with a novel chromosomal translocation.

Nucleolar organizer regions (NORs) staining and proliferating cell nuclear antigen (PCNA) immunostaining in mucosa-associated lymphoid tissue (MALT) gastric lymphomas

Nucleolar organizer region-associated proteins (AgNOR) and proliferating cell nuclear antigen (PCNA) have been studied by means of a silver staining technique and immunohistochemistry, in paraffin-embedded, gastrectomy specimens of 12 low-grade and 13 high-grade gastric MALT lymphomas respectively. A significant difference was found between the AgNOR count and PCNA index of low-grade lymphomas (mean AgNOR count 2.5 and mean PCNA index 8.33%) and high-grade lymphomas (mean AgNOR count 8.67 and mean PCNA index 49.7%). It is suggested that both methods are useful adjuncts to histopathology for the distinction between low and high grade gastric MALT lymphomas. We also found heterogeneity in AgNOR counts and PCNA index among individual cases of either low or high grade MALT gastric lymphomas. This suggests that the AgNOR count and PCNA index is helpful in the individual approach of the proliferation rate of each tumour, a parameter of potential importance for predicting the biological behaviour of the tumour and the prognosis of the disease.

Peritoneal sarcoidosis. An unrecognized cause of sclerosing peritonitis

In a Caucasian woman with a history of ocular and pulmonary sarcoidosis, the occurrence of sclerosing peritonitis with exudative ascites but without any of the well-known causes of this syndrome prompts us to consider that sclerosing peritonitis is a manifestation of sarcoidosis. The dramatic improvement that occurred on corticosteroid therapy adds credibility to this previously unreported association.

Primary B-cell gastric lymphomas of mucosa-associated lymphoid tissue. Histological and immunohistochemical study of ten cases on surgical specimens

Ten cases of gastric mucosa-associated lymphoid-tissue B-cell lymphoma were studied on surgical specimens by histology and immunohistochemistry, with monoclonal and polyclonal antibodies for B- and T-cells. For the first time, percentage of centroblast-like cells was appreciated, using their LN1 positivity, by opposition to the negativity of centrocyte-like cells (LN2 immunoreactivity alone). Lymphomas were divided into four main groups: A) centrocyte-like cells; B) centrocyte-like cells and immunocytoma; C) centrocyte-like cells admixed to centroblast-like cells; and D) centrocyte-like cells, immunocytoma and at least 30% of centroblast-like cells. Group C was divided into 3 subgroups: C1 (rare centroblast-like cells); C2 (30-50% of centroblast-like cells); and C3 (predominant centroblast-like cells). Therefore low grade (A, B, C1) and high grade malignancy groups (C2, C3, D) were identified: this preliminary subdivision could be extended in larger series and applied to mucosa-associated lymphoid-tissue lymphoma from other sites. Furthermore, the possible prognostic significance of this subdivision could be evaluated by correlation with long term follow-up.

[Celiac disease and collagenous colitis. A fortuitous association]

We report the cases of two patients with coeliac disease in whom chronic diarrhoea persisted in spite of strict adherence to a gluten free-diet and regression of intestinal villous atrophy. Collagenous colitis was evidenced in both patients. Six cases of such association have already been described. Because of subepithelial deposition of collagen in the colon of collagenous colitis and in the small intestine of coeliac disease, it has been suggested that the colonic collagen band might reflect a toxic effect of gluten on colonic epithelium. However, thickening of the colonic collagen band during strict gluten free-diet, as observed in one of our cases, is not in favour of this hypothesis.

Effect of peroperative hypertension on 125I-albumin uptake by vein graft media

Aortocoronary bypass, in use for over 20 years, is followed by lesions in 80% of vein grafts after 10 years. In 8 patients (mean age 60, SD = 7.8) before cardiopulmonary bypass, segments of saphenous vein were harvested, and following hydraulic distension (760 mmHg x 10 min), stripped of adventitia, de-endothelialized, cannulated, immersed in oxygenated Krebs solution pH 7.4 37 deg C, and pressurized (100 mmHg) with 4% 125I-albumin-Evans blue for two hours. The samples were then frozen, and serially sectioned in the plane of the lumenal surface. The radioactivity of the 20 microns-thick sections was then determined, and expressed as a tissue: labelled solution concentration ratio (cpm unit volume wet tissue/cpm unit volume labelled solution). Distended portions had a higher mean transmural concentration ratio, as compared with the undistended portion; the ratio distended/undistended was 1.23, SD = 0.17, n = 8, p less than 0.01 (paired t test). This suggests alteration in the transport properties of vein interstitium by hypertension. Random histologic examination of native veins revealed no structural damage apart from age-related dystrophy of elastic fibres and intimal and medial fibrosis in grossly normal veins. These results suggest that the quality of the vein used, combined with hypertension during its preparation, may be factors in the genesis of postoperative graft failure.

Peripheral T-cell lymphoma or Hodgkin's disease in a HIV seropositive patient: a histopathological study

Malignant lymphomas occurring in patients with AIDS are usually derived from the B-cell lineage while T-cell malignant lymphomas are very rare in these patients. We report a HIV seropositive 29-year-old homosexual man in whom cervical lymph node biopsy showed an atypical lymphoproliferative process. On morphological and paraffin section immunohistochemical grounds the possibility of Hodgkin's disease (HD) mixed cellularity was initially suggested, but frozen section immunohistochemical studies revealed that the cellular infiltrate exhibited an aberrant pan T immunophenotype and consequently the diagnosis of peripheral T-malignant lymphomas (T-ML) was made. However, genotypic studies would be required to definitely confirm this diagnosis, in such cases. In our case, varying numbers of small and medium-sized cells were positive for both Leu 3/CD4 and Leu 2/CD8 whereas some large cells reacted only with Leu 3/CD4 antibody. Some medium-sized, large and giant cells showed cytoplasmic positivity for Leu M1/CD15. Furthermore, the positivity of many large and giant cells with the activation markers BerH2/CD30, Ki-1/CD30, Tac/CD25 and HLA-DR suggested an activation state for these cells. Our findings emphasize the usefulness of frozen section immunohistochemical methods in order to investigate the spectrum of lymphoid malignancies occurring in HIV seropositive patients, and confirm results of previous studies which stressed the diagnostic difficulties that may appear in distinguishing HD from peripheral T-ML.

Peculiar acute toxic colitis after ingestion of colocynth: a clinicopathological study of three cases

We report three examples of toxic acute colitis which occurred after ingestion of colocynth (Citrullus colocynthis) for ritual purposes. The prominent clinical feature was dysenteric diarrhoea; colonoscopic changes included congestion and hyperaemia of the mucosa with abundant exudates but no ulceration or pseudopolyp formation. A causal relationship between colonic injury and the intake of colocynth was supported by the following features: (1) the pharmacology of the colocynth extract ingested; (2) the temporal relationship between colocynth intake and clinical onset (eight to 12 h); (3) the rapid recovery within three to six days, with normal endoscopy at day 14; (4) the absence of other possible causes for the observed patterns, except in one case, in which a concomitant intestinal infection with Clostridium perfringens Type A was discovered; (5) the specific pathological features. Colonic biopsies taken 27, 44, and 72 h after colocynth intake showed: erosions with fibrino-purulent exudate, early fibrosis of the lamina propria, hyaline thickening of the superficial epithelial basal membrane. These pathological features completely disappeared within 14 days in all three cases.

[Oxyurid granuloma of the mesentery]

A 44-year-old woman presented with an acute abdominal syndrome associated with fever. Laparotomy revealed a mesenteric mass; pathology demonstrated a granuloma containing an adult threadworm (Enterobius vermicularis) and its eggs. Ectopic oxyuriasis is rare, and only three cases of peritoneal granuloma distant from the pelvis or the appendix have been reported previously. Our observation is the first case to which a clinical symptomatology could be ascribed. The pathogenesis and the treatment of this particular localization of oxyuriasis are discussed.

Aortic 125I-albumin transport in patients with Marfan's syndrome and annuloaortic ectasia

The morphologic, biochemical, and mechanical abnormalities of connective tissue fibrous proteins in Marfan's syndrome have been well studied, and their role in cardiovascular complications is well accepted. Less is known, however, about the state of the amorphous components of the aortic connective tissue. In the course of a study of transmural transport in blood vessels, we have had the opportunity to study dystrophic aorta from two young men who survived elective surgery; both with aortic insufficiency (AI) histologically compatible with Marfan's syndrome. One had recurrent chronic dissecting aneurysm (RCDA) as well. The aorta of the first (but not the second) was histologically compatible with Marfan's syndrome. Fresh specimens of intact ascending aorta were incubated in Krebs solution, pH 7.4, containing 125I-labelled bovine serum albumin for 2 h at 37 degrees C. The samples were then frozen, and serially sectioned in the plane of the lumenal surface. The radioactivity of the 20-micron thick sections was then determined, and expressed as a tissue/labelled solution concentration ratio. Transmural profiles of these ratios revealed no difference between the aorta of the RCDA patient with non-specific aortic dystrophy, and that of a 70-year-old man undergoing aortocoronary bypass. However, in the patient with aortic histology compatible with Marfan's syndrome, the average media concentration ratio was 5-fold less (4% vs. 20%).

A primary immunoblastic T malignant lymphoma of the small bowel, with azurophilic intracytoplasmic granules. A histologic, immunologic, and electron microscopy study

We report an aggressive primary T-immunoblastic lymphoma of the small intestine without blood involvement or associated celiac disease. Grossly, the tumor was composed of multiple disseminated ulcerated, infiltrating, or protuberant nodular lesions. Immunologic investigation showed that lymphoma cells were of peripheral (post-thymic) T-cell origin and expressed the phenotype associated with cytotoxic-suppressor subset (Leu4/CD3+, Leu9/CD7+, Leu2/CD8+, Leu11/CD16+, Leu 7/NKcells+, FcIgG+, HLA-DR+, anti-Tac/CD25+, Ki-1/CD30-, Leu1/CD5-, Leu5/CD2-, Leu3/CD4-). A particular morphologic feature of this case is the presence of numerous azurophilic granules within the lymphoma cells, identified as lysosomes by cytochemical and ultrastructural studies. In view of recent immunologic evidence that normal cytotoxic/suppressor T-cells selectively reside within the epithelium of the normal bowel and some of them contain azurophilic granules, it could be suggested that our patient's lymphoma represents a malignant counterpart of these lymphocytes. Furthermore, the aggressive character of this T malignant lymphoma (T-ML) could be related to the expression of T-cell activation markers HLA-DR and Tac/CD25 and the proliferation-associated antigen Ki-67 on a high proportion of tumor cells.

Primary gastric peripheral T-cell malignant lymphoma with helper/inducer phenotype. First case report with a complete histological ultrastructural and immunochemical study

Primary gastrointestinal T-cell malignant lymphomas (T-ML) are very rare. In this case report we describe a primary gastric tumor with local lymph node involvement. On the basis of histologic, immunohistochemical, and electron microscopic studies, the authors classified this tumor as a pleomorphic T-ML, large cell variant with peripheral helper/inducer T-cell phenotype (Leu1/CD5+, Leu4/CD3+, Leu5/CD2+, Leu9/CD7+, and Leu3/CD4+). The extreme pleomorphism of lymphoma cells, the numerous giant cells, and the presence of tumor nodules with two or three concentric layers were the three striking morphologic features of our case. Tumor cells showed an inconstant but true positive staining with anti-LeuM1/CD15 and LeuM3/CD14 antibodies. Vimentin positivity could be related to the presence of intermediate filaments at ultrastructural level. Neuron-specific enolase reactivity was a peculiar but unexplained feature. Furthermore, the positivity of the surface markers Ki-1/CD30, anti-Tac/CD25 and HLA-DR, and the nuclear marker Ki-67 suggested an activation state and a high proliferative activity of the tumor cells. This study emphasizes the usefulness of combined pathologic methods in order to rule other diagnoses such as undifferentiated carcinoma, malignant melanoma, malignant histiocytosis, B-cell lymphoma and interdigitating reticulum cells sarcoma, in view of an extremely polymorph tumor proliferation. This is apparently the first completely documented case report of a primary gastric pleomorphic T-ML of peripheral T-cell origin.

Primary gastric peripheral T-cell malignant lymphoma with helper/inducer phenotype. First case report with a complete histological ultrastructural and immunochemical study

Primary gastrointestinal T-cell malignant lymphomas (T-ML) are very rare. In this case report we describe a primary gastric tumor with local lymph node involvement. On the basis of histologic, immunohistochemical, and electron microscopic studies, the authors classified this tumor as a pleomorphic T-ML, large cell variant with peripheral helper/inducer T-cell phenotype (Leu1/CD5+, Leu4/CD3+, Leu5/CD2+, Leu9/CD7+, and Leu3/CD4+). The extreme pleomorphism of lymphoma cells, the numerous giant cells, and the presence of tumor nodules with two or three concentric layers were the three striking morphologic features of our case. Tumor cells showed an inconstant but true positive staining with anti-LeuM1/CD15 and LeuM3/CD14 antibodies. Vimentin positivity could be related to the presence of intermediate filaments at ultrastructural level. Neuron-specific enolase reactivity was a peculiar but unexplained feature. Furthermore, the positivity of the surface markers Ki-1/CD30, anti-Tac/CD25 and HLA-DR, and the nuclear marker Ki-67 suggested an activation state and a high proliferative activity of the tumor cells. This study emphasizes the usefulness of combined pathologic methods in order to rule other diagnoses such as undifferentiated carcinoma, malignant melanoma, malignant histiocytosis, B-cell lymphoma and interdigitating reticulum cells sarcoma, in view of an extremely polymorph tumor proliferation. This is apparently the first completely documented case report of a primary gastric pleomorphic T-ML of peripheral T-cell origin.