Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
1.
Sci Rep ; 11(1): 9343, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33927276

RESUMO

The precise characterization of the lobular architecture of the liver has been subject of investigation since the earliest historical publications, but an accurate model to describe the hepatic lobular microanatomy is yet to be proposed. Our aim was to evaluate whether Voronoi diagrams can be used to describe the classic liver lobular architecture. We examined the histology of normal porcine and human livers and analyzed the geometric relationships of various microanatomic structures utilizing digital tools. The Voronoi diagram model described the organization of the hepatic classic lobules with overall accuracy nearly 90% based on known histologic landmarks. We have also designed a Voronoi-based algorithm of hepatic zonation, which also showed an overall zonal accuracy of nearly 90%. Therefore, we have presented evidence that Voronoi diagrams represent the basis of the two-dimensional organization of the normal liver and that this concept may have wide applicability in liver pathology and research.


Assuntos
Fígado/anatomia & histologia , Animais , Biometria , Humanos , Suínos
2.
Surg Endosc ; 20(2): 298-301, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16362469

RESUMO

BACKGROUND: Minimally invasive esophagectomy (MIE) is an evolving surgical alternative to traditional open esophagectomy. Despite considerable technical challenges, it was hypothesized that MIE could be performed effectively by surgeons experienced in open esophageal resection and advanced laparoscopic surgery. The authors report their experience with 25 patients who underwent MIE for esophageal disease. METHODS: A multidisciplinary esophageal cancer team evaluated all the patients enrolled in this institutional review board-approved retrospective review study. Over an 18-month period, 25 consecutive patients (22 men and 3 women; mean age, 62 years; range, 48-77 years) with resectable esophageal cancer underwent MIE. Six patients were treated with neoadjuvant chemoradiotherapy. The preoperative diagnoses were adenocarcinoma (64%, n = 16), high-grade dysplasia (20%, n = 5), and squamous cell cancer (16%, n = 4). The outcomes evaluated included operative course, hospital and intensive care unit lengths of stay, pathologic stage, morbidity, and mortality. RESULTS: Two patients required conversion to open esophagectomy. Operative mortality was 4% (n = 1). The mean operative time was 350 min (range, 300-480), and the average blood loss was 200 ml. The patients remained ventilated for a median of 12 h, and the median intensive care unit utilization was 1 day. The median hospital length of stay was 9 days (range, 6-33 days). Major complications occurred in 32% of the patients. The anastomotic leak rate was 12%. Minor pulmonary complications occurred in 32% and atrial fibrillation in 16% of the patients. An anastomotic stricture developed in 24% of all the patients. One patient showed a positive proximal margin in the final pathology results. CONCLUSIONS: Minimally invasive esophagectomy is a technically challenging procedure that can be performed safely at the Virginia Piper Cancer Institute. Optimal results require appropriate patient selection and a multidisciplinary team experienced in the management of esophageal cancer.


Assuntos
Adenocarcinoma/cirurgia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia , Laparoscopia , Procedimentos Cirúrgicos Minimamente Invasivos , Idoso , Anastomose Cirúrgica/efeitos adversos , Fibrilação Atrial/etiologia , Perda Sanguínea Cirúrgica , Cuidados Críticos , Doenças do Esôfago/cirurgia , Esofagectomia/efeitos adversos , Esofagectomia/mortalidade , Feminino , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/mortalidade , Tempo de Internação , Pneumopatias/etiologia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/mortalidade , Respiração Artificial , Estudos Retrospectivos , Fatores de Tempo
3.
Br J Surg ; 91(11): 1479-84, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15386327

RESUMO

BACKGROUND: Treatment of patients with malignant large bowel polyps is highly dependent on pathological evaluation. The aim of this study was to evaluate interobserver variability in the pathological assessment of endoscopically removed polyps. METHODS: The records of 88 patients with colorectal cancer who underwent endoscopic removal of malignant polyps were reviewed. Study investigators reviewed the initial pathology report; three experienced gastrointestinal pathologists reviewed all slides in a blinded fashion. Interobserver variability of pathological assessment of malignant polyps was analysed by kappa statistics. RESULTS: Seventy-six (86 per cent) of the 88 patients had malignant polyps and 12 (14 per cent) had carcinoma in situ. Agreement between experienced pathologists was substantial with regard to T stage (kappa = 0.725), resection margin status (kappa = 0.668) and Haggitt's classification (kappa = 0.682), but comparison of initial and experienced pathologists' assessment demonstrated only moderate agreement in these areas (kappa = 0.516, kappa = 0.555 and kappa = 0.578 respectively). Agreement between even experienced pathologists was poor with respect to histological grade of differentiated adenocarcinomas (kappa = 0.163) and angiolymphatic vessel invasion (kappa = - 0.017). CONCLUSION: Pathological assessment of malignant polyps varies between observers. Specialist pathologists appear to have a higher degree of consensus among themselves than with generalist pathologists with respect to T stage. The high interobserver variability with regard to histological grade of differentiated tumours is clinically irrelevant. However, variability in the assessment of angiolymphatic vessel invasion limits the value of this measurement for clinical decision making.


Assuntos
Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia Gastrointestinal/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador
5.
J Hepatol ; 35(3): 338-43, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11592594

RESUMO

BACKGROUND/AIMS: It is unclear whether treatment of patients with Budd-Chiari syndrome (BCS) should be based on liver histology, as large histopathological studies have not been performed. We investigated the relationship between the histopathological findings and survival. METHODS: We studied the clinical features and findings on biopsy specimens in 45 patients with BCS who were admitted to four tertiary referral medical centers. Histological findings, i.e. congestion, necrosis, inflammation and fibrosis, were graded. Survival was assessed in relation to histological findings and clinical features at the time of diagnosis as well as in relation to subsequent treatment with or without portosystemic shunting. RESULTS: Centrilobular congestion, centrilobular necrosis, lobular inflammation and portal inflammation were not significantly related to survival. In addition, there was no association between either pericentral or periportal fibrosis and survival. Univariate analysis revealed that the prothrombin time and Child-Pugh score were significantly related to survival (P = 0.005 and Ptrend = 0.02, respectively). Multivariate analysis yielded the Child-Pugh score, serum alanine aminotransferase (ALT) and treatment with portosystemic shunting as independent prognostic indicators. CONCLUSIONS: We found no evidence for a relationship between early liver pathology and survival. Child-Pugh score, serum ALT and portosystemic shunting appeared to be prognostic indicators for patients with BCS.


Assuntos
Síndrome de Budd-Chiari/patologia , Fígado/patologia , Adolescente , Adulto , Idoso , Biópsia , Síndrome de Budd-Chiari/mortalidade , Síndrome de Budd-Chiari/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Derivação Portossistêmica Cirúrgica , Prognóstico , Taxa de Sobrevida
6.
Endoscopy ; 33(9): 791-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11558034

RESUMO

BACKGROUND AND STUDY AIMS: Endoscopic mucosectomy has been performed for early cancers and dysplastic lesions < or = 2 cm in diameter. The feasibility and safety of mucosectomy for circumferential lesions of the esophagus is uncertain. The aim of this study was to determine the technical feasibility, as well as the short and long-term complication rates, with circumferential endoscopic mucosectomy of the distal esophagus in the pig. MATERIALS AND METHODS: Circumferential endoscopic mucosectomy of the distal 3 cm of the esophagus was performed in four pigs, using a cap mucosectomy device. The animals were sacrificed after 30, 50, 70, and 90 days to assess mucosal regeneration and stricture formation. RESULTS: The procedure time for circumferential endoscopic mucosectomy was 15-30 min. Circumferential endoscopic mucosectomy was technically feasible and without short-term complications. Videotapes of all resections were reviewed to ensure that complete removal of the mucosa was achieved. All mucosectomy specimens underwent histological evaluation. The specimens included the mucosa alone in three of the pigs. Some of the specimens in the fourth pig included a superficial layer of muscularis propria. This pig failed to thrive. Macroscopic examination of the dissected esophageal specimens from the healthy pigs revealed a well-healed, normal-appearing esophagus, whereas a stenosis of 4 x 10 mm was observed in the distal esophagus of the pig that failed to thrive. CONCLUSIONS: Circumferential endoscopic mucosectomy of the porcine distal esophagus is feasible and safe. An adequate submucosal saline cushion is essential to prevent stenosis due to deep injury.


Assuntos
Endoscopia do Sistema Digestório , Esôfago/cirurgia , Mucosa/cirurgia , Animais , Segurança de Equipamentos , Estudos de Viabilidade , Feminino , Modelos Animais , Suínos , Resultado do Tratamento
7.
Liver Transpl ; 7(7): 608-14, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11460228

RESUMO

Although nonalcoholic steatohepatitis (NASH) has generally been considered a benign condition, the increasing prevalence and severity of obesity has heightened concerns about the frequency with which NASH progresses to end-stage liver disease. The aim of this study is to determine the frequency, clinical features, and posttransplantation history of decompensated liver disease secondary to NASH. The frequency of NASH as a cause of end-stage liver disease was prospectively determined in patients evaluated for liver transplantation. NASH was considered to be the primary cause of liver disease in patients who had histological evidence of steatohepatitis and in whom chronic liver diseases other than NASH were excluded. Posttransplantation histological characteristics were also determined in patients with NASH and compared with those of patients with pretransplantation diagnoses of cholestatic liver diseases, alcoholic disease, and hepatitis C. Of 1,207 patients evaluated for liver transplantation during the study period, 31 patients (2.6%) had NASH as the primary cause of liver disease. In the same period, 546 liver transplantations were performed, 16 of which (2.9%) were for end-stage disease secondary to NASH. Posttransplantation steatosis was seen in 60% of transplant recipients with NASH versus 5% of those with cholestatic disease, 15% of those with alcoholic disease, and 15% of those with hepatitis C. Steatohepatitis recurred in 33% of transplant recipients with NASH, with progression to cirrhosis in 12.5%. NASH can progress to end-stage liver disease in a minority of affected patients and was the primary cause of liver disease in 2.9% of patients evaluated for liver transplantation at our center. Recurrence of steatosis and NASH is frequent and can be severe after liver transplantation.


Assuntos
Fígado Gorduroso/complicações , Falência Hepática/etiologia , Adulto , Idoso , Progressão da Doença , Fígado Gorduroso/patologia , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Falência Hepática/patologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias
8.
Mod Pathol ; 14(6): 615-22, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11406665

RESUMO

The cell of origin and direction of differentiation of the clear cell tumor of the lung (the so-called sugar tumor) remains enigmatic. Recognition of HMB-45 immunoreactivity and identification of melanosomes have suggested a relationship to angiomyolipoma of kidney or liver and lymphangiomyoma. This has given rise to the concept that clear cell tumors are neoplasms of so-called perivascular epithelioid cells--PEComas. Herein we report the existence of four similar tumors occurring in extrapulmonary sites, one of which had malignant features. The three benign tumors occurred in females ages 9, 20, and 40 years; two were located in the rectum and one in the vulva. The malignant tumor occurred in the inter-atrial cardiac septum of a 29-year-old man. Common histologic features were a richly vascular organoid architecture, tumor cells with clear to pale eosinophilic cytoplasm, abundant glycogen, and immunoreactivity for HMB 45, but not S100, multiple keratin, neuroendocrine, or muscle markers. Benign tumors demonstrated low mitotic activity, no necrosis, and good circumscription; the malignant tumor showed considerable mitotic activity, necrosis, and an infiltrative growth pattern. Ultrastructurally, glycogen was present, mitochondria were abundant, and membrane-bound lamellated bodies consistent with premelanosomes were present in two cases, and equivocal in one. Because these tumors have light microscopic, immunohistochemical, and electron microscopic features similar to pulmonary sugar tumors, we propose the name primary extrapulmonary sugar tumor (PEST) for them. Although most PEST's are probably benign, malignant forms appear to exist. These cases further support the concept of a family of systemic HMB-45 positive tumors that include sugar tumors, angiomyolipoma of kidney or liver, lymphangiomyomas, and clear-cell myomelanocytic tumors of the falciform ligament/ligamentum teres.


Assuntos
Adenocarcinoma de Células Claras/patologia , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/ultraestrutura , Adulto , Antígenos de Neoplasias , Criança , Células Epitelioides/patologia , Evolução Fatal , Feminino , Septos Cardíacos , Humanos , Imuno-Histoquímica , Masculino , Antígenos Específicos de Melanoma , Microscopia Eletrônica , Proteínas de Neoplasias/análise , Reto , Vulva
10.
Dis Colon Rectum ; 44(3): 341-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11289278

RESUMO

PURPOSE: Squamous and adenosquamous carcinoma of the colon and proximal rectum are rare neoplasms in which the clinicopathologic behavior and the most appropriate management are unknown. The purpose of this study was to review the histology and clinical course of the largest series of cases ever reported from a single center on this rare condition. METHOD: The Mayo Clinic tissue registry was searched for all primary cases of squamous and adenosquamous carcinoma of the colon or rectum proximal to 8 cm from the dentate and presenting before December 31, 1992. Of the 52 identified cases there was adequate histologic material for review in 44 cases. These cases were divided into pure squamous-cell carcinoma (n = 11), mixed adenosquamous carcinoma (n = 31), and adenocarcinoma with benign-appearing squamous metaplasia (adenoacanthoma; n = 2). Squamous-cell carcinomas were examined for evidence of human papilloma virus by in situ hybridization. A retrospective review of medical records was undertaken in all 52 cases with respect to predisposing factors, clinicopathologic behavior, prognostic features, and treatment with adjuvant therapy. RESULTS: The charts of 52 patients (20 females), with a mean age of 58.6 (range, 19-90) years, were reviewed. Right-sided lesions were the most common (43 percent). Metastatic disease was evident at presentation in 49 percent of patients, the most common sites in order being liver, peritoneal, and lung. The five-year overall survival rate was 34 percent, Stage I to III disease had a 65 percent five-year survival rate, and Stage IV mean survival time was 8.5 months. For node-positive and node-negative disease, 23 and 85 percent, respectively, survived five years. There was no evidence of human papilloma virus in the six squamous-cell carcinomas examined. CONCLUSION: Squamous and adenosquamous carcinomas of the colon and rectum are rare neoplasms. Although a poor prognosis can be expected for node-positive disease, patients with negative nodes do generally the same as patients with adenocarcinoma histology. Based on advances made with multimodality therapy of squamous-cell cancer of the anus and adenocarcinoma of the rectum, further studies should define the role of postoperative therapies for these lesions.


Assuntos
Adenocarcinoma/diagnóstico , Carcinoma Adenoescamoso/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Colorretais/diagnóstico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoescamoso/mortalidade , Carcinoma Adenoescamoso/patologia , Carcinoma Adenoescamoso/cirurgia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
11.
Gastroenterology ; 119(6): 1631-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11113084

RESUMO

BACKGROUND & AIMS: The epidemiology of primary biliary cirrhosis (PBC) has not been studied systematically in the United States. We report the incidence and prevalence of this condition in the general population. We also examined the validity of the Mayo natural history model for PBC among these unselected patients from the community. METHODS: The Rochester Epidemiology Project entails a computerized index of diagnoses from the health care encounters of residents of Olmsted County, Minnesota. For potential cases identified using this database, the complete (inpatient and outpatient) medical records were reviewed to verify the diagnosis and extract information necessary for the application of the Mayo model. We estimated the incidence and prevalence of PBC in this population and compared the actual survival of patients with PBC in the community with the survival predicted for PBC patients by the Mayo natural history model. RESULTS: The age-adjusted (to 1990 U.S. whites) incidence of PBC per 100,000 person-years for years 1975-1995 was 4.5 (95% confidence interval [CI], 3.1-5.9) for women, 0.7 (95% CI, 0.1-1.3) for men, and 2.7 (95% CI, 1.9-3.5) overall. The age- and sex-adjusted prevalence per 100,000 persons as of 1995 was 65.4 (95% CI, 43.0-87.9) for women, 12.1 (95% CI, 1.1-23.1) for men, and 40.2 (95% CI, 27.2-53.1) overall. The Mayo natural history model accurately predicted the actual survival of these patients. CONCLUSIONS: This first description of the epidemiology of PBC in the United States indicates that its incidence and prevalence in this country are among the highest reported. Outcomes among these unselected patients from a community population further validated the Mayo natural history model of PBC.


Assuntos
Cirrose Hepática Biliar/epidemiologia , Cirrose Hepática Biliar/fisiopatologia , Previsões , Incidência , Minnesota , Modelos Teóricos , Prevalência , Análise de Sobrevida
12.
Hepatology ; 32(5): 1125-30, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11050065

RESUMO

Approximately half of patients undergoing liver transplantation (LT) for hepatitis C virus (HCV) develop histologic evidence of recurrence within the first postoperative year. Early identification of recipients at risk for more severe recurrence of HCV may be useful in selecting patients for antiviral therapy. We determined whether recipients at greatest risk for more severe recurrence of HCV can be identified by pre- and/or early post-LT HCV-RNA levels in serum or tissue. Serum and tissue samples were prospectively collected pre-LT and at 7 days, 4 months, 1 year, and at 3 years posttransplantation from patients undergoing LT for HCV. Hepatitis activity index (HAI) and fibrosis stage (FS) were assessed in all liver biopsies. Forty-seven patients (32 men) were studied. Higher HCV-RNA levels at 4 months post-LT (>/=10(9) copies/mL, n = 29) were associated with higher HAI at 1 year and at 3 years post-LT. The HAI seen on protocol biopsies at 4 months correlated significantly with fibrosis stage (FS) at 1 year (r =.56, P

Assuntos
Hepatite C/patologia , Hepatite C/cirurgia , Transplante de Fígado , Fígado/patologia , Doença Aguda , Progressão da Doença , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Hepacivirus/genética , Hepatite C/metabolismo , Hepatite C/virologia , Humanos , Terapia de Imunossupressão/efeitos adversos , Fígado/metabolismo , Masculino , Metilprednisolona/efeitos adversos , Metilprednisolona/uso terapêutico , Estudos Prospectivos , RNA Viral/sangue , RNA Viral/metabolismo , Recidiva , Fatores de Tempo , Carga Viral
13.
Am J Gastroenterol ; 95(9): 2333-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11007238

RESUMO

OBJECTIVE: This study was designed to evaluate the safety and estimate the efficacy of oral budesonide in patients with primary sclerosing cholangitis (PSC). METHODS: Twenty-one patients with PSC were treated with 9 mg daily of oral budesonide for 1 yr. RESULTS: Significant, but marginally important, improvement in serum alkaline phosphatase (1,235 +/- 190 vs 951 +/-206 U/L, p = 0.003) and AST levels (119 +/- 14 vs 103 +/- 19 U/L, p = 0.02) was noted at the end of the treatment period. Serum bilirubin levels increased significantly in the 18 patients who completed 1 yr of treatment (1.1 +/- 0.1 vs 1.4 +/- 0.3, p = 0.01) and no significant changes in liver tests were noted 3 months after budesonide was discontinued. The Mayo risk score did not change significantly, and although a significant improvement in the degree of portal inflammation was noted at the end of the treatment period, the degree of fibrosis and stage of disease were not significantly affected. There was a marked loss of bone mass of the femoral neck (0.851 +/- 0.02 vs 0.826 +/- 0.02 g/cm2, p = 0.002) and lumbar spine (1.042 +/- 0.02 vs 1.029 +/- 0.02 g/cm2, p = 0.09) at 1 yr of treatment with budesonide. Two patients required evaluation for liver transplantation during treatment, and two patients developed cosmetic side effects. CONCLUSIONS: Oral budesonide appears to be of minimal, if any, benefit and it is associated with a significant worsening of osteoporosis in patients with PSC.


Assuntos
Anti-Inflamatórios/uso terapêutico , Budesonida/uso terapêutico , Colangite Esclerosante/tratamento farmacológico , Administração Oral , Adulto , Idoso , Fosfatase Alcalina/sangue , Anti-Inflamatórios/administração & dosagem , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biomarcadores/sangue , Biópsia , Budesonida/administração & dosagem , Colangite Esclerosante/sangue , Colangite Esclerosante/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prognóstico , Segurança
14.
Transplantation ; 70(2): 292-7, 2000 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10933151

RESUMO

BACKGROUND: End-stage liver disease for which no cause can be identified, cryptogenic cirrhosis, is a common indication for liver transplantation. Allograft inflammation and fibrosis have been reported to recur with similar frequencies after liver transplantation for cryptogenic cirrhosis and hepatitis C (HCV). METHODS: We determined sequential posttransplant allograft histology in four groups of recipients: 31 transplanted for cryptogenic cirrhosis, 70 for cholestatic etiologies, 40 for alcoholic liver disease, and 56 for HCV. Modified hepatitis activity index (HAI) and fibrosis stage were determined at 4 months, 1 year, and at most recent biopsy posttransplantation. RESULTS: The prevalence of HAI > or = 2 among cryptogenic recipients was similar to that of cholestatic and alcoholic recipients at 4 months, 1 year, and at most recent evaluation (mean 45+/-17 months posttransplantation). For HCV-infected recipients, the frequency of HAI > or = 2 was more than for cryptogenic recipients at 1 year (52 vs. 29%, P=0.04) and at most recent evaluation (64 vs. 15%, P=0.003). Fibrosis scores for cryptogenic, cholestatic, and alcoholic recipients were similar at all timepoints. The proportion of HCV-infected recipients with fibrosis stage >2 was more than that of cryptogenic recipients at 4 months (29 vs. 12%, P=0.05), 1 years (46 vs. 7%, P=0.0002), and at most recent evaluation (42 vs. 15%, P=0.06). None of the cryptogenic recipients developed cirrhosis. RESULTS: The frequency of elevated HAI and fibrosis stage in recipients who undergo transplantation for cryptogenic cirrhosis is similar to that of recipients who undergo transplantation for cholestatic etiologies and significantly less than that of HCV-infected recipients. Fibrosis stage and HAI are generally stable after transplantation for cryptogenic cirrhosis. These data do not suggest a viral etiology of liver disease in the majority of patients with cryptogenic cirrhosis.


Assuntos
Colestase Intra-Hepática/cirurgia , Hepatite C/cirurgia , Cirrose Hepática Alcoólica/cirurgia , Cirrose Hepática/cirurgia , Transplante de Fígado , Transplante Homólogo/patologia , Biópsia , Fígado Gorduroso/patologia , Humanos , Tolerância Imunológica/fisiologia , Fígado/patologia , Cirrose Hepática/etiologia , Transplante de Fígado/patologia , Masculino
15.
Mod Pathol ; 13(3): 229-37, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10757333

RESUMO

After orthotopic liver transplantation (OLT), patients with chronic hepatitis C virus (HCV) infection show nearly universal persistence of viremia and reinfection of the liver, but identifying the point at which the liver is reinfected morphologically can be difficult. One tool that may potentially be useful to detect reinfection is reverse transcriptase-polymerase chain reaction (RT-PCR), which has proven to be highly sensitive for detecting HCV RNA in formalin-fixed paraffin-embedded liver tissue. Our purpose was to gain insight into the time frame of HCV reinfection by assaying for HCV RNA in serial posttransplant liver biopsy specimens. Our study population consisted of 14 patients who underwent liver transplantation for hepatitis C and had confirmed HCV RNA in pretransplant serum, absence of HCV RNA in donor livers, and available consecutive posttransplant liver allograft specimens. We performed RT-PCR for HCV RNA in serial posttransplant liver biopsy specimens, beginning at 1 week until at least one biopsy from each tested positive. HCV RNA was detected in liver tissue by RT-PCR in 1-week post-OLT liver samples in 6 of 14 (42.8%) patients, the earliest being 5 days post-OLT. Eventually, each of the remaining eight samples became RT-PCR positive as well; the first detections occurred in these at 3 weeks (three cases), 4 weeks (three cases), 48 weeks (one case), and 144 weeks (one case). Histologic identification of hepatitis C recurrence was relatively insensitive in relation to these molecular data. These data suggest that (1) HCV RNA reinfection is nearly universal after liver transplantation in patients with chronic hepatitis C infection, (2) molecular reinfection by HCV occurs at a variable interval post-OLT, with the majority of allograft livers reinfected as early as 1 week, and (3) morphologic features of hepatitis C are usually appreciable at the time of "molecular" recurrence.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C Crônica/diagnóstico , Transplante de Fígado , Fígado/patologia , RNA Viral/análise , Viremia/diagnóstico , Hepacivirus/genética , Hepatite C Crônica/cirurgia , Hepatite C Crônica/virologia , Humanos , Fígado/cirurgia , Fígado/virologia , Recidiva , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Transplante Homólogo , Viremia/virologia
16.
Abdom Imaging ; 25(1): 38-44, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10652919

RESUMO

BACKGROUND: The purpose of the study was to describe the computed tomographic (CT) findings of the alimentary canal and mesentery in amyloid infiltration of the gastrointestinal (GI) tract and to correlate the CT findings with histologic extent and distribution and with amyloid subtype. METHODS: Abdominal CT scans performed between 1988 and 1997 on patients with pathologically proven amyloidosis of the alimentary canal and mesentery. Histology was graded for extent of mucosal, submucosal, and muscularis propria involvement and for degree of interstitial and vascular distribution. CT findings were correlated with histologic extent, histologic distribution, and amyloid histochemical type. RESULTS: Twenty-three patients were included. Four (17%) had bowel wall thickening, which was associated with a higher submucosal extent and interstitial distribution than in patients with normal bowel by CT. Four (17%) patients had bowel wall dilatation without thickening, which was not associated with statistically significantly different histology than in patients with normal bowel by CT. There was no statistically significant correlation between CT findings and histochemical subtype. Mesenteric soft tissue infiltration was seen in two patients, and mesenteric adenopathy was seen in one patient. CONCLUSIONS: Normal bowel is a common abdominal CT finding in amyloidosis of the alimentary canal. When findings are present, GI wall thickening and/or bowel wall dilatation without wall thickening may be seen. Bowel wall thickening on CT correlates with submucosal extent and interstitial distribution of disease. Soft tissue infiltration and adenopathy are also occasionally seen.


Assuntos
Amiloidose/diagnóstico por imagem , Enteropatias/diagnóstico por imagem , Mucosa Intestinal/patologia , Intestino Delgado/diagnóstico por imagem , Radiografia Abdominal/métodos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose/patologia , Diagnóstico Diferencial , Feminino , Humanos , Enteropatias/metabolismo , Enteropatias/patologia , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Mesentério/diagnóstico por imagem , Mesentério/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Am J Gastroenterol ; 94(11): 3310-3, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566735

RESUMO

OBJECTIVE: The aim of this study was to determine the time course over which patients with primary sclerosing cholangitis (PSC) progress through the histological stages of the disease. METHODS: One hundred seven patients with PSC who had at least two liver biopsies were identified. The stage information from two consecutive biopsies formed one observation and a continuous time Markov model was used to describe the rate of progression between biopsies. RESULTS: Three hundred seven liver biopsies were performed in the 107 patients giving a total of 200 observations. At 1 yr, 42% of patients in stage II disease progress, 66% at 2 yr, and 93% at 5 yr; whereas 14% of patients in stage III progress at 1 yr, 25% at 2 yr, and 52% at 5 yr. The frequency of progression of stage I disease could not be determined because of the small number of patients in stage I. Regression of histological stage was observed in 30 of 200 total observations (15%), and in 30 of 85 observations (35%) in which there was a change in stage. CONCLUSIONS: These data regarding histological progression in PSC may be potentially helpful in determining the number of patients and length of time necessary to appreciate a treatment effect in clinical trials. However, the high degree of sampling variability in PSC may restrict the usefulness of serial liver biopsies as a means of evaluating treatment efficacy.


Assuntos
Colangite Esclerosante/patologia , Adolescente , Adulto , Idoso , Biópsia , Colagogos e Coleréticos/uso terapêutico , Colangite Esclerosante/classificação , Colangite Esclerosante/tratamento farmacológico , Colangite Esclerosante/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Hepatite/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática Biliar/patologia , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Necrose , Penicilamina/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Ácido Ursodesoxicólico/uso terapêutico
18.
Am J Surg Pathol ; 23(11): 1328-39, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10555001

RESUMO

In contrast to all other vascularized organ allografts, chronic rejection (CR) of the liver is potentially reversible. We therefore studied demographic, perioperative, biochemical, and histologic features associated with reversibility or progression to graft failure. Using very stringent clinical and histological criteria, we identified a subgroup of 23 of 916 patients receiving primary liver allografts with CR from the Liver Transplantation Database. Of these, 13 experienced graft failure as a result of CR, and 10 patients recovered to normal histology or liver injury test results. Male-to-female sex mismatch (p = 0.07), younger recipient age (p = 0.09), younger donor age (p = 0.06), white-to-white race match (p = 0.09), primary diagnosis of biliary atresia (p = 0.02), and cold ischemia time of more than 12 hours (p = 0.02) were associated with graft failure. Patients who eventually recovered from CR were more likely to have acute rejection within the first 2 weeks (70% vs 23%; p = 0.04), had a higher number of acute rejection episodes (p = 0.08), and were more likely to have been treated with OKT3 (90% vs 46%, p = 0.07). Although overlap existed in the histopathologic findings between the patients whose grafts failed and those who recovered, those patients who developed bile duct loss in more than 50% of the portal tracts (p < 0.01), severe (bridging) perivenular fibrosis (p = 0.05), and the presence of foam cell clusters (p = 0.06) were more likely to require retransplantation. In contrast to other solid organ allografts, CR of the liver is not an irreversible process. These findings can be used to understand the evolution of CR and to design a biologically correct and clinically relevant staging system.


Assuntos
Rejeição de Enxerto , Transplante de Fígado , Adolescente , Adulto , Criança , Pré-Escolar , Doença Crônica , Progressão da Doença , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/patologia , Humanos , Terapia de Imunossupressão , Lactente , Transplante de Fígado/patologia , Masculino , Pessoa de Meia-Idade
19.
Hepatology ; 30(6): 1356-62, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10573511

RESUMO

Nonalcoholic steatohepatitis (NASH) may present with increased hepatic fibrosis progressing to end-stage liver disease. No factors that determine increasing fibrosis and histologically advanced disease have been recognized, thus, liver biopsy is recommended in all patients for diagnosis and prognosis. Our aim was to identify independent predictors of severe hepatic fibrosis in patients with NASH. One hundred and forty-four patients were studied. All patients underwent liver biopsy. Clinical and biochemical variables were examined with univariate and multivariate analysis. Thirty-seven (26%) patients had no abnormal fibrosis, 53 (37%) had mild fibrosis, 15 (10%) had moderate fibrosis, 14 (10%) had bridging fibrosis, and 25 (17%) had cirrhosis. In multivariate analysis, older age (P =. 001), obesity (P =.002), diabetes mellitus (P =.009), and aspartate transaminase/alanine transaminase (AST/ALT) ratio greater than 1 (P =.03) were significant predictors of severe liver fibrosis (bridging/cirrhosis). Body mass index (P =.003) was the only independent predictor of the degree of fat infiltration. Increased transferrin saturation correlated positively with the severity of fibrosis (P =.02) in univariate analysis, and there was a trend for more female patients among those with more advanced fibrosis (P =. 09). However, iron studies or gender were not significant when controlled for age, obesity, diabetes, and AST/ALT ratio. In conclusion, older age, obesity, and presence of diabetes mellitus help identify those NASH patients who might have severe liver fibrosis. This is the subgroup of patients with NASH who would be expected to derive the most benefit from having a liver biopsy and considering investigational therapies.


Assuntos
Fígado Gorduroso/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Alcoolismo , Análise de Variância , Biópsia , Índice de Massa Corporal , Criança , Árvores de Decisões , Complicações do Diabetes , Diabetes Mellitus/fisiopatologia , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/patologia , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/fisiopatologia , Prognóstico , Fatores de Risco
20.
Hepatology ; 30(6): 1398-404, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10573518

RESUMO

Cholangiocarcinoma is a highly-malignant adenocarcinoma originating from cholangiocytes. Current concepts support escape from immune surveillance using aberrant expression of Fas ligand (FasL) and dysregulation of receptor (FasR) signaling as a potential mechanism for tumor progression. Our aims were to determine if altered expression of FasR and FasL or changes in expression of FLICE inhibitor (I-FLICE) allow cholangiocarcinoma cells to escape immune surveillance. Human cholangiocarcinoma cell lines were evaluated for the functional expression of FasR and FasL by (1) quantitating apoptosis after incubation of cells with agonistic antibodies and (2) an in vitro cell death assay involving coculture of cholangiocarcinoma cells with Fas-sensitive thymocytes. I-FLICE antisense treatment was performed by stable transfection with complementary DNA (cDNA) for I-FLICE in the reverse orientation. We found that normal cholangiocytes in vivo express FasL. Human cholangiocarcinoma cell lines express both FasL and FasR and I-FLICE. FasL expressed by cholangiocarcinomas in vitro induced lymphocyte cell death (70% after 24 hours). Despite the expression of FasR, exposure of the cells to agonistic antibodies (500 ng/mL) induced only minimal apoptosis in the Jurkat cells. Antisense treatment of cholangiocarcinomas in vitro with I-FLICE reduced protein expression of I-FLICE by 90% to 95% and increased Fas-mediated apoptosis 2-fold. We concluded that cholangiocarcinomas escape immune surveillance either by disabling FasR signaling through the expression of I-FLICE and/or increased FasL expression to induce apoptosis of invading T cells. Reduction of I-FLICE expression in cholangiocarcinoma cells restored Fas-mediated apoptosis. Therapeutic maneuvers to inhibit expression of I-FLICE may aid in the treatment of cholangiocarcinoma.


Assuntos
Proteínas de Arabidopsis , Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Glicoproteínas de Membrana/metabolismo , Receptor fas/metabolismo , Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Caspase 8 , Caspase 9 , Caspases/genética , Colangiocarcinoma/imunologia , Colangiocarcinoma/patologia , Técnicas de Cocultura , Regulação para Baixo , Proteína Ligante Fas , Ácidos Graxos Dessaturases/genética , Humanos , Glicoproteínas de Membrana/agonistas , Modelos Biológicos , RNA Antissenso/genética , RNA Antissenso/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Células Tumorais Cultivadas , Receptor fas/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...