Human epidermal growth factor receptor-2 and estrogen receptor expression, a demonstration project using the residual tissue repository of the Surveillance, Epidemiology, and End Results (SEER) program.

BACKGROUND: In 2001, the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program established Residual Tissue Repositories (RTR) in the Hawaii, Iowa, and Los Angeles Tumor Registries to collect discarded tissue blocks from pathologic laboratories within their catchment areas. To validate the utility of the RTR for supplementing SEER's central database, we assessed human epidermal growth factor receptor-2 (HER2) and estrogen receptor expression (ER) in a demonstration project. MATERIALS: Using a prepared set of tissue microarrays (TMAs) residing in the Hawaii Tumor Registry (HTR), we performed standard immunohistochemistry. Breast cancers in the TMA were diagnosed in 1995, followed through 2006, and linked to SEER's main database. RESULTS: The TMA included 354 cases, representing 51% of 687 breast cancers in the HTR (1995). The HTR and TMA cases were similar with respect to patient demographics and tumor characteristics. Seventy-six percent (76%, 268 of 354) of TMA cases were HER2+ and/or ER+, i.e., 28 HER2+ER-, 12 HER2+ER+, and 228 HER2-ER+. There were 67 HER2-ER- cases and 19 were unclassified. Age distributions at diagnosis were bimodal with dominant early-onset modes for HER2+ER- tumors and dominant late-onset modes for HER2-ER+ breast cancers. Epidemiologic patterns for concordant HER2+ER+ (double-positive) and HER2-ER- (double-negative) were intermediate to discordant HER2+ER- and HER2-ER+. CONCLUSION: Results showed contrasting incidence patterns for HER2+ (HER2+ER-) and ER+ (HER2-ER+) breast cancers, diagnosed in 1995. Though sample sizes were small, this demonstration project validates the potential utility of the RTR for supplementing the SEER program.

The comparative importance of E. coli antigen in granulomatous colitis of Boxer dogs.

Granulomatous colitis of Boxer dogs is characterized by mucosal and submucosal infiltration by abundant large macrophages and lymphocytes and plasma cells. Involved intestine is thickened, corrugated and ulcerated. The macrophages that occur in colon, cecum and regional lymph nodes are PAS-positive, lipid-rich, contain cholesterol, and some of the time can be seen to hold bacteria. Paraffin tissue blocks of formalin-fixed colon and colic lymph nodes from 10 cases were cut at 5 microm and immunostained by a streptavidin-biotin immunoperoxidase technique, employing primary antibodies against Escherichia coli, E. coli 0157: 2, Campylobacter, C. jejuni-coli, Yersinia pseudotuberculosis, Salmonella, Shigella, Pseudomonas and Lawsonia intracellularis. The macrophages in the lamina propria and submucosa, as well as those in aggregates in regional lymph nodes, showed immunoreactivity with polyclonal E. coli antibody in all 10 cases. Tissues lacking granulomas were negative, as were those reacted with the other eight antibodies, with the exception that there was rare focal staining for Campylobacter, Lawsonia and Salmonella in a few dogs. We believe these results identify the causative agent of this granulomatous disease of Boxer dogs, a disease with great histologic and etiologic similarity to granulomatous leptomeningitis of Beagle dogs, and malacoplakia and xanthogranulomatous cholecystitis of man. Macrophages that are immunopositive for E. coli antigen occur in Crohn's disease as well, where their significance is less well understood.

Gene amplification as means for determining therapeutic strategies in human cancers.

Pharmacogenomic analysis aspires to identify individuals with specific genetic characteristics in order to predict a positive response or reduce a negative response to a therapeutic modality. While the search continues for the many single nucleotide polymorphisms which will be used in such genetic analyses, other genetic alterations in specific cell types have proven useful in determining the potential for response to therapy. One such genetic alteration is amplification of entire gene sequences which results in overexpression of a gene product or protein. Amplification of the HER2 (neu, erbB-2) oncogene is found in up to 35% of human breast cancers and is associated with a poor prognosis. In addition, this genetic alteration may predict response to various therapeutic modalities. Assays are available to detect the HER2 protein receptor or copies of the HER2 gene sequence to determine eligibility for Herceptin treatment or adriamycin treatment in node positive patients, respectively. This model represents a somatic event used in the functional determination of a therapeutic strategy.

p185HER2 overexpression in human breast cancer using molecular and immunohistochemical methods.

With the successful clinical trials of the engineered antibody Herceptin (in advanced-stage breast cancer) and adriamycin-based chemotherapy regimens (in the adjuvant setting), the need to detect p185HER2 overexpression or associated amplification of the coding gene HER2 in breast cancer patients is escalating. Twenty to 30% of breast carcinomas have overexpression of p185HER2. This condition correlates with poor patient prognosis and predicts response to chemotherapy in lymph node-positive patients. In this study we compare quantitation of p185HER2 in breast cancer at the gene and protein levels using differential polymerase chain reaction (PCR) and immunohistochemistry, respectively. To assign HER2 gene copy numbers, a calibration curve was constructed using normal breast epithelia and breast carcinoma cell lines having known dosages of amplified HER2. We found corresponding molecular and immunohistochemical results in 85% of the 13 paraffin-embedded breast carcinoma cases examined. Two cases were found to have minimum gene amplification but marked p185HER2 overexpression, suggesting an alternative mechanism to overexpression such as transcriptional activation. Although the differential PCR assay exhibits saturation approaching 20 HER2 gene copies, this may not be clinically significant because the immunohistochemical assay also appears to saturate in this gene copy number range.

Primary PNET of kidney: report of two cases and review of literature.

PNET of the kidney is a rare tumor with only a few published reports. In view of poorer prognosis and different therapeutic approach, renal PNET should therefore be differentiated from other primary renal neoplasma such as Wilms tumor, renal neuroblastoma and malignant rhabdoid tumor which on histology resemble renal PNET. Two cases of renal PNET have been described in this report. Cut surface of the tumor in both cases was greyish white lobulated, with multiple tiny cystic areas. Histologically, tumor consisted of loosely cohesive sheets of small to medium sized monomorphic cells with round nuclei and little cytoplasm. Tumor cells showed diffuse strong membrane positivity for MIC2 and focal weak to moderate positivity for NSE and vimentin. Renal PNET should therefore be included in differential diagnosis of rapidly enlarging renal lumps presenting with local infiltration and aggressive behaviour, particularly in children and young adults. Diffuse strong membrane positivity for MIC2 in PNET is helpful in differentiating it from other primary renal neoplasms.

The use of monoclonal antibody R92F6 and polymerase chain reaction to confirm the presence of parvovirus B19 in bone marrow specimens of patients with acquired immunodeficiency syndrome.

BACKGROUND: Parvovirus B19 infection is a cause of chronic anemia and red cell aplasia in patients with acquired immunodeficiency syndrome (AIDS) and in other immunocompromised hosts. Anemia in AIDS patients has a multifactorial etiology, with parvovirus B19 infection being an infrequent but nevertheless treatable cause. Therapy with intravenous immune globulin can result in rapid improvement of parvovirus-induced anemia. This treatment is expensive, therefore accurate and rapid confirmation of parvovirus infection is important in providing appropriate and cost-effective therapy. METHODS: Bone marrow samples from 2 AIDS patients with severe anemia and reticulocytopenia were studied. Bone marrow morphology and serologic studies were evaluated for parvovirus B19 infection. An immunohistochemical method using a monoclonal antibody, R92F6, to B19 capsid proteins was utilized on decalcified, B5-fixed, paraffin-embedded bone marrow biopsies. Bone marrow aspirate cells were examined by electron microscopy for evidence of viral particles. In addition, polymerase chain reaction (PCR) studies using a nested PCR assay to the parvovirus B19 viral genome were performed in a case for which fresh cells were available. RESULTS: Bone marrow findings included marked erythroid hypoplasia with characteristic giant pronormoblasts and intranuclear inclusions. Serologic studies were negative in one case, while the second case showed positive parvovirus B19 immunoglobulin M antibody. Immunohistochemical studies for parvovirus B19 were positive in both cases. The presence of intranuclear virions was demonstrated by electron microscopy and was confirmed by PCR analysis. Both patients were treated with intravenous immune globulin, and subsequent improvement was noted. CONCLUSIONS: Both immunohistochemistry and PCR studies on bone marrow specimens from AIDS patients with anemia are rapid and sensitive methods for the confirmation of parvovirus B19 infection. They are valuable tools, particularly when serologic studies are negative. When PCR is not available, immunohistochemical methods can be useful. The rapid confirmation of parvovirus B19 infection will allow for early and cost-effective therapy.

Immunohistochemical detection of Listeria antigens in the placenta in perinatal listeriosis.

Listeria monocytogenes, a worldwide pathogen, causes significant perinatal mortality and morbidity and has been implicated in spontaneous abortions, still-births, premature delivery, and neonatal sepsis, often with meningitis. Maternal symptoms are frequently minimal, and diagnosis is made only if the suspicion is high and diagnostic maternal blood or amniotic fluid cultures are performed. Because cultures are not routinely performed on spontaneously aborted fetuses, many authors feel that the true incidence of the disease may be underestimated. To date, the absence of a test to retrospectively diagnose Listeria infection has contributed to the lack of accurate estimates of the incidence of the disease. Seven cases in which immunohistochemical stains were used to confirm the diagnosis of placental listeriosis are described. All placentas showed the characteristic lesions with severe chorioamnionitis, numerous microabscesses, and focal necrotizing villitis. Immunohistochemical localization of Listeria antigen was made to the amnion (focally in areas with no inflammatory infiltrate), the abscesses, and the areas with villitis. In general, the antigen was extracellular and intracellular, predominantly within macrophages or the amnion epithelium. Listeria antigen was often found where definite identification of the organism was not possible on Brown-Hopps or Warthin-Starry stains. The immunohistochemical technique may therefore show an increase in sensitivity of detection of L monocytogenes compared with routine bacterial stains. Moreover, the ability to retrospectively evaluate placental specimens for evidence of this organism should permit the true incidence of perinatal listeriosis to be determined.

Case report: an autopsy study of a rare T-cell lymphoma clinically misdiagnosed as fulminant hepatic disease.

We describe a case of a 73-year-old male with a rare T-cell lymphoma that presented deceptively as progressive hepatic failure with fever, weight loss, pancytopenia, mental confusion, splenomegaly, and no lymphadenopathy. An alcoholic history supported the diagnosis of cirrhosis, but a liver biopsy was not performed. A bone marrow biopsy was considered unremarkable. Death occurred after a course of four months. Postmortem examination showed hepatic, splenic, lymph node, and marrow infiltration by characteristically sparse, isolated, bizarre, medium-to-large sized neoplastic cells with extensive hepatic centrilobular necrosis, steatosis, and predominant splenic involvement. Immunohistochemical markers indicated a T-cell lymphoma consistent with either an alpha/beta peripheral T-cell lymphoma or a gamma/delta lymphoma. Definitive immunotyping was not available. However, the pathologic features are most consistent with a gamma/delta T-cell lymphoma. This case is an example of a rare, rapidly progressive lymphoma, which is a recognized clinical entity, easily missed, and treatable. Its diagnostic consideration must be explicitly communicated to pathologists, because the isolated or sparse tumor cells in a lymph node, liver, or bone marrow biopsy may easily be mistaken for variants of megakaryocytes or histiocytes.

Viral RNA in duodenal bile of cirrhotic patients with chronic hepatitis C.

BACKGROUND: Hepatitis C virus (HCV) has been detected in blood, saliva, urine, semen, breast milk, and tears. To our knowledge, bile has not yet been investigated. We observed histologic immunoreactivity in bile with an antibody to c100 protein in four of five HCV-positive cirrhotic livers, but also in two HCV-negative controls owing to a focally present cross-reacting antigen. METHODS: We collected duodenal bile from 13 cirrhotic patients during endoscopic evaluation of varices (10 HCV, three controls) and assayed for HCV by reverse transcriptase polymerase chain reaction. RESULTS: Viral RNA was detected in the bile of 8 of 10 seropositive patients and in 0 of 3 seronegative controls. CONCLUSION: Hepatitis C virus RNA and an antigen immunoreactive with anti-c100 protein are present in bile in a proportion of cirrhotic patients with chronic HCV. It remains to be determined whether the virus is intact or degenerate, and whether it is shed into bile from hepatocytes or is a contaminant from blood or other secretions.

Local delivery of c-myb antisense oligonucleotides during balloon angioplasty.

Intraluminal delivery of antisense oligonucleotides to c-myb was assessed following balloon angioplasty in swine peripheral arteries. Successful delivery and intramural persistence of oligonucleotide for over 24 h were demonstrated following angioplasty with hydrogel balloons coated with 32P-labeled antisense. Delivery of fluorescein-labeled antisense demonstrated further localization within the arterial media and intracellularly. Preliminary in vitro studies demonstrated the feasibility of inhibition of porcine lymphocyte proliferation using the murine antisense to c-myb. Twelve iliac or carotid arteries underwent angioplasty with antisense-coated balloons, while the contralateral vessels underwent angioplasty with the same-sized balloons coated with the complementary sense strand. Six to seven days later, dilated arterial segments were surgically isolated. In 10 of 12 vessel pairs, antisense-treated vessels demonstrated less cellular proliferation than did contralateral sense-treated vessels, as assessed by quantitative immunohistochemical staining of proliferating cell nuclear antigen, and smooth muscle cell proliferation was reduced 18% in antisense-treated vessels compared to the contralateral sense-treated vessels (PCNA-positive nuclear area: 7.7 +/- 4.9% vs. 9.3 +/- 5.2%, P < 0.04)-intraluminal delivery of antisense oligonucleotides to c-myb is feasible with a catheter-based system and may reduce smooth muscle cell proliferation following arterial injury.

Immunoperoxidase staining of tumors by an antibody to Xenopus pNiXa.

pNiXa, a serpin from oocytes and embryos of Xenopus laevis, was tested as a tumor marker in human and rodent tissues. A peptide corresponding to the histidine-rich domain of pNiXa was conjugated and administered to rabbits to produce a polyclonal antibody, which was purified by antigen-affinity and used for immunoperoxidase staining of formalin-fixed, paraffin-embedded tissue sections. Staining with pNiXa-antibody was positive in 23/187 human tumors (12 percent) and negative in 119 specimens of normal human tissues. Positive reactions were more frequent in liver (38 percent) and colon (34 percent) tumors than breast (18 percent), prostate (9 percent), mesothelioma (20 percent) or lung (0 percent) tumors. Staining was negative in human tumors from other sites. Rodent tumors and preneoplastic foci induced by chemical carcinogens were surveyed for staining with pNiXa-antibody. Staining was positive in 10/10 hepatic lesions (hepatocellular foci, adenomas, carcinomas) induced in hybrid D2B6F1 mice by diethylnitrosamine and phenobarbital, whereas murine mammary tumors and thyroid, pituitary, renal, and colon tumors of F-344/CNr rats were negative. Thus, immunostaining with pNiXa-antibody identifies a subset of human and murine tumors; further studies are needed to determine if reactivity of pNiXa-antibody has diagnostic or prognostic significance.

The relationship of granulomas to blood vessels in intestinal Crohn's disease.

It has been suggested that granulomatous vasculitis is a primary mechanism in the production of pathologic changes seen in Crohn's disease. We set out to investigate the relationship of granulomas to blood vessels and to confirm or refute previous reports of granulomatous vasculitis in Crohn's disease. Thirty paraffin embedded tissues from 11 patients with Crohn's disease were selected after examination of H&E stained sections for the presence of granulomas. Using an immunohistochemical method, various monoclonal antibodies were applied to sequential sections from each tissue to demonstrate vascular structures and granulomas. In three patients none of the granulomas occurred in association with blood vessels, in five a small proportion of the granulomas affected blood vessels, and in three granulomatous vasculitis appeared occlusive and significant. A total of 232 granulomas were identified, 22% of which were closely associated with blood vessels, which included both arteries and veins; 16% were perivascular, while 6% were intravascular. Perivascular granulomas did not surround blood vessels or invade the medial layers. They were asymmetric, suggesting that they originated by encroachment of nearby lymphatic or connective tissue granulomas. These results indicate that the granulomas of Crohn's disease are usually not associated with blood vessels; however, there is a minority of patients in whom vascular granulomatous inflammation may be important, although probably as a secondary phenomenon.

Bacterial translocation to mesenteric lymph nodes is increased in cirrhotic rats with ascites.

BACKGROUND/AIMS: Cirrhotic patients are predisposed to develop spontaneous bacteremias and/or peritonitis, mainly caused by enteric bacteria. The aim of this study was to investigate if bacterial translocation, which is the passage of bacteria from the intestinal lumen to regional lymph nodes and/or the systemic circulation, is increased in a rat model of cirrhosis. METHODS: Rats were studied after 12-16 weeks of CCl4 inhalation, when samples of mesenteric lymph nodes, blood, liver, and spleen for standard bacteriologic cultures and a fragment of colon and liver for histology were obtained. Immunostaining of the cecum was performed using a polyclonal anti-Escherichia coli antibody. RESULTS: A significantly greater proportion of rats with cirrhosis and ascites (5 of 9; 56%) had positive mesenteric lymph node cultures compared with cirrhotics without ascites (0 of 9) and normal controls (0 of 12) (P < 0.01). In one cirrhotic rat, E. coli was isolated from both mesenteric lymph nodes and ascites. Rats with cirrhosis and ascites had significantly greater cecal submucosal edema and inflammation than rats with no ascites and controls. Immunoreactivity with E. coli was present in the cecal wall in 3 of 5 animals with E. coli translocation to mesenteric lymph nodes. CONCLUSIONS: In cirrhotic rats, bacterial translocation is increased after the development of ascites and may be a major factor in the development of spontaneous infections in cirrhosis.

Immunocytochemical evidence of Listeria, Escherichia coli, and Streptococcus antigens in Crohn's disease.

BACKGROUND/AIMS: Infectious agents have long been suspected of playing a role in the initiation of Crohn's disease. The objective of this study was to search for likely microbial agents in diseased tissues using immunocytochemical techniques. METHODS: Intestines and mesenteric lymph node specimens of 21 patients from two French families with a high frequency of Crohn's disease and from Connecticut were studied. The microbial agents searched for included Bacteroides vulgatus, Borrelia burgdorferi, Escherichia coli, Listeria monocytogenes, Streptococcus spp., bovine viral diarrhea virus, influenza A virus, measles virus, parainfluenza virus, and respiratory syncytial virus. RESULTS: Seventy-five percent of the patients with Crohn's disease (12 of 16) were positively labeled with the antibody to Listeria. Macrophages and giant cells immunolabeled for this antigen were distributed underneath ulcers, along fissures, around abscesses, within the lamina propria, in granulomas, and in the germinal centers of mesenteric lymph nodes. In addition, 57% (12 of 21) of the cases contained the E. coli antigen, and 44% (7 of 16) contained the streptococcal antigen. The immunolabeling for the latter two agents also occurred within macrophages and giant cells, distributed in a pattern similar to that of Listeria antigen. CONCLUSIONS: The results suggest that Listeria spp., E. coli, and streptococci, but not measles virus, play a role in the pathogenesis of Crohn's disease.

Immunohistochemical localization of acetaminophen in target tissues of the CD-1 mouse: correspondence of covalent binding with toxicity.

Administration of hepatotoxic doses of acetaminophen (APAP) to mice results in necrosis, not only of liver cells but of renal proximal tubules and bronchiolar and olfactory epithelium. In the liver, covalent binding is localized to the centrilobular hepatocytes which later undergo necrosis. This study was undertaken to compare the cellular distribution of bound APAP in all four major target tissues with that of cytochrome P4502E1 (a P450 isoenzyme commonly associated with APAP bioactivation), with emphasis on the cell types which later undergo necrosis. Tissues were collected from mice at selected times after APAP administration (600 mg/kg, po) and fixed by microwave irradiation for immunohistochemistry, or in formalin for histopathological study. Immunohistochemical localization of bound APAP was performed on 5-microns paraffin sections using an affinity-purified anti-APAP antibody. Similar tissues from naive mice were used for immunohistochemical localization of cytochrome P4502E1 (using a polyclonal sheep anti-P4502E1 antibody). Positive staining with both the anti-APAP and the anti-P4502E1 antibodies was similar in distribution, being present in the cell types which become damaged by APAP in all four target tissues. These results demonstrate that covalent binding and subsequent necrosis are localized in common with cytochrome P4502E1, suggesting that, as in the liver, toxicity in extrahepatic targets is also related to the ability of these tissues to activate APAP in situ.

Decreased platelet deposition and smooth muscle cell proliferation after intramural heparin delivery with hydrogel-coated balloons.

BACKGROUND: In vitro and in vivo studies have demonstrated both anticoagulant and antiproliferative effects of heparin. The purpose of this study was to assess the effect of local intramural delivery of heparin, using heparin-coated hydrogel balloons, on platelet deposition and early smooth muscle cell proliferation after in vivo balloon angioplasty. METHODS AND RESULTS: The effects of local heparin delivery were assessed during balloon angioplasty of porcine peripheral arteries. All balloon dilatations were performed with oversized hydrogel balloons coated with a known quantity of heparin. Balloon dilatations in contralateral vessels with uncoated hydrogel balloons served as study controls. The pharmacokinetics of heparin delivery were assessed using 3H-heparin to quantitate heparin wash-off from the balloon surface, heparin delivery to the arterial wall, and intramural persistence of drug. Platelet deposition at 1 hour after balloon injury was quantified using 111In-labeled platelets. Smooth muscle cell proliferation was assessed 6 to 7 days after angioplasty with immunohistochemical staining for proliferating cell nuclear antigen. 3H-heparin wash-off from the hydrogel balloon surface occurred rapidly, with approximately 95% of the heparin coating disappearing within 10 seconds in the intact circulation. Approximately 2% of heparin on the balloon surface was delivered intramurally at the time of angioplasty. Intramural heparin dissipated rapidly, although small amounts of intramural heparin could still be detected for at least 48 hours. In comparison to control vessels, there was less 111In-platelet deposition (P = .002) and less medial smooth muscle cell proliferation (P = .03) in heparin-treated vessels. CONCLUSIONS: Local intraluminal delivery of heparin at the time of balloon angioplasty with heparin-coated hydrogel balloons results in intramural deposition of drug that persists for at least 48 hours. This in vivo technique significantly decreases platelet deposition and early smooth muscle cell proliferation after angioplasty injury.

Atypical seminoma--histologic features, immunohistochemical characterization, and correlation with survival.

Classical seminoma and embryonal carcinoma are two points in the spectrum of histologic differentiation in testicular germ cell tumors. The validity of an intermediate category, ie, atypical seminoma (AS) is questionable. Histopathologic and clinical data on 42 patients treated for primary testicular germ cell tumor from 1975 to 1985 were reviewed. Twenty-seven cases were identified as classical seminoma and nine were embryonal carcinoma. The remaining six cases were somewhat problematic to classify, combining the growth pattern of seminoma with cytologic features of embryonal carcinoma. Immunocytochemically, four of these tumors suggested some progression towards the embryonal carcinoma phenotype on the basis of cytokeratin expression. Survival for classical seminoma, AS, and embryonal carcinoma were 90%, 80%, and 63% respectively (mean follow-up, 8.6 years). Although the survival differences were not statistically significant, when considered with morphologic and selected immunocytochemical data, they tend to support the concept of an AS as an intermediate lesion between classical seminoma and embryonal carcinoma.

Placental site trophoblastic tumor: a report of radiologic, surgical, and pathologic methods of evaluating the extent of disease.

A dramatic vaginal hemorrhage occurred 1 year after a normal vaginal delivery. A curettage showed placental site trophoblastic tumor. Magnetic resonance imaging and color flow Doppler documented a marked increase in uterine vascularity, as well as an abnormal endomyometrial appearance. Surgery included total abdominal hysterectomy and pelvic lymph node dissection. This confirmed the extensive uterine tumor and also showed an extremely small focus of tumor cells in one lymph node. Immunohistochemical staining for human placental lactogen and for cytokeratin confirmed the histologic finding. After surgery, we gave adjuvant chemotherapy with the EMACO regimen. The radiologic, surgical, and pathologic procedures utilized in this case provided a more complete understanding of the extent of her disease. These techniques may be helpful in making therapeutic decisions for other women with this rare disorder.

An immunocytochemical search for infectious agents in Crohn's disease.

Microorganisms have long been suspected of causing Crohn's disease (CD); however, an etiologic agent has yet to be identified. Few studies have employed immunocytochemistry (ICC) to examine tissue from patients with CD for microbial antigens. We investigated 36 formalin-fixed tissues from 16 patients with CD with ICC. No evidence of adenovirus, Borrelia, Brucella, BVDV, Campylobacter, Campylobacter-like organisms, Chlamydia, coronavirus, CMV, EBV, Legionella, mycobacteria, Pseudomonas, rotavirus, Salmonella, Shigella, staphylococci, Toxoplasma gondii, Treponema, or Yersinia was found. ICC identified E. coli and streptococcal antigens in 11 (69%) and 10 (63%) of the 16 cases studied, respectively. Escherichia coli immunoreactivity was located in ulcers, within the lamina propria, and along fissures. Streptococcal immunolabeling occurred within mucosal epithelial cells, in the lamina propria, in ulcers, along fissures, in granulomatous inflammation including multinucleate giant cells, and in lymph nodes. These results suggest that some of the granulomas in CD may result from immunologic processing of bacterial antigens following their penetration through a compromised mucosa. E. coli and streptococcal antigens may contribute to the pathogenesis of CD.

An in-depth study of Crohn's disease in two French families.

BACKGROUND: Two French families were investigated. In the first a husband, wife, and 4 children had Crohn's disease; in the second 7 of 11 children had the disease. There was no history of Crohn's disease in antecedent generations and no linkage to HLA haplotypes. METHODS: Methods included family interviews; review of medical records, radiographs, and pathology slides; serology; selective stool culture; enzyme-linked immunosorbent assay for fecal viral detection; and immunocytochemistry. RESULTS: In both families multiple cases occurred among siblings in 7-13-month periods. There appeared to be a 4-8-year recurrence of new disease in both families. Radiographs showed a remarkable similarity in the pattern of disease, confined to distal ileum and cecum, in the members of family 1. Examination for pathology showed granulomas in all 8 patients for whom tissues were available. Acid-fast organisms or Campylobacter-like organisms were not found in tissue sections, and immunocytochemistry was negative for mycobacteria and Yersinia. Stool cultures were negative for mycobacteria, Yersinia, and Mycoplasma. Torovirus and coronavirus antigens were not found in stool. Serology was negative for antibodies to Brucella, Yersinia, influenza, and three enteropathogenic viruses of animals. CONCLUSIONS: The circumstances and data suggest that an infectious microorganism is responsible for these clusterings of Crohn's disease.