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Dive into the research topics where Alan N. Langnas is active.

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Featured researches published by Alan N. Langnas.


Annals of Surgery | 2005

2003 Report of the Intestine Transplant Registry: A New Era Has Dawned

David R. Grant; Kareem Abu-Elmagd; Jorge Reyes; Andreas G. Tzakis; Alan N. Langnas; Thomas M. Fishbein; Olivier Goulet; Douglas G. Farmer

Summary Background Data:The intestine has been more difficult to transplant than other solid organs. We analyzed registry data to determine the scope and success of intestine transplantation in the current era. Methods:All known intestinal-transplant programs participated. Patient- and graft-survival estimates were obtained using the Kaplan-Meier product limit method and were analyzed with the Wilcoxon statistic. Results:Sixty-one programs provided data on 989 grafts in 923 patients. Four patients were lost to follow-up. The short-gut syndrome was the most common primary indication for transplantation. Sixty-one percent of the recipients were ≤18 years. Proportionally more combined intestinal and liver transplants were performed in this group. More than 80% of all current survivors had stopped parenteral nutrition and resumed normal daily activities. A multivariate analysis of cases within the last 5 years revealed that transplantation of patients waiting at home, recipient age, antibody induction immune suppression, and center experience with at least 10 cases were associated with improved patient survival. One-year graft survival rates of 81% were achieved in patients who were induced with antithymocyte globulin and maintained on tacrolimus. Conclusions:Transplantation is an effective therapy for the treatment of patients with end-stage intestine failure who cannot tolerate parenteral nutrition. With newer immune suppressive protocols, 1-year graft and patient survival rates approach the results of liver transplantation. Further improvement in survival are expected with early referral since suitable donor organs are scarce and survival rates are better when patients are well enough to wait at home for their transplant.


American Journal of Surgery | 1991

Vascular complications after orthotopic liver transplantation

Alan N. Langnas; Wagner Marujo; Robert J. Stratta; R. Patrick Wood; Byers W. Shaw

Over a 57-month period, we performed 430 orthotopic liver transplants in 372 patients. A total of 38 vascular complications were identified including hepatic artery thrombosis (n = 24), portal vein thrombosis (n = 6), combined hepatic artery thrombosis/portal vein thrombosis (n = 3), and hepatic artery rupture (n = 5). A number of potential risk factors for the development of vascular thrombosis were evaluated with only children, weight less than 10 kg, and cold ischemia time found to be significant. The clinical presentation included fulminant hepatic failure, allograft dysfunction, biliary sepsis, and screening ultrasound. Duplex ultrasonography was diagnostic in nearly all cases. Therapeutic modalities included revascularization, revascularization followed by retransplantation, retransplantation alone, and observation. Five cases of hepatic artery rupture occurred in four patients. Infectious arteritis was present in four patients. The 6-month actuarial survival in patients with vascular complications was 70%. Early diagnosis is critical for graft salvage, with surgical intervention the mainstay of therapy.


Transplantation | 2006

A Report of the Vancouver Forum on the Care of the Live Organ Donor: Lung, Liver, Pancreas, and Intestine Data and Medical Guidelines

Mark L. Barr; Jacques Belghiti; Federico G. Villamil; Elizabeth A. Pomfret; David S. Sutherland; Rainer W. G. Gruessner; Alan N. Langnas; Francis L. Delmonico

An international conference of transplant physicians, surgeons, and allied health professionals was held in Vancouver, Canada, on September 15 and 16, 2005 to address the care of the live lung, liver, pancreas, and intestine organ donor. The Vancouver Forum was convened under the auspices of the Ethics Committee of The Transplantation Society. Forum participants included over 100 leaders in organ transplantation, representing many countries from around the world, including participants from the following continents: Africa, Asia, Australia, Europe, North and South America. The objective of the Vancouver Forum was to develop an international standard of care for the live lung, liver, pancreas and intestinal organ donor. This Vancouver Forum followed a conference convened in Amsterdam on the care of the live kidney donor (1, 2). There were four organ specific work groups at the Vancouver Forum: lung, liver, pancreas and intestine. Each organ work group addressed the following topics in concert and reported their findings in a plenary presentation to all participants:


American Journal of Transplantation | 2002

Radiochemotherapy and Transplantation Allow Long‐Term Survival For Nonresectable Hilar Cholangiocarcinoma

Debra Sudan; Arnaud DeRoover; Srinath Chinnakotla; Ira J. Fox; Byers W. Shaw; Tim McCashland; Mike Sorrell; Margaret A. Tempero; Alan N. Langnas

Results of liver transplantation in the treatment of cholangiocarcinoma have been poor as a result of the high incidence of locoregional dissemination and tumor recurrence. This study evaluates the effect of neoadjuvant chemoradiation therapy combined with orthotopic liver transplantation in a carefully selected group of patients with hilar cholangiocarcinoma.


Clinical Infectious Diseases | 1998

Invasive Pulmonary Aspergillosis Due to Aspergillus terreus: 12-Year Experience and Review of the Literature

Peter C. Iwen; Mark E. Rupp; Alan N. Langnas; Elizabeth C. Reed; Steven H. Hinrichs

A 12-year retrospective analysis was done to identify and evaluate in detail cases of invasive pulmonary aspergillosis (IPA) caused by Aspergillus terreus. We identified 13 A. terreus infections among 133 total cases of confirmed invasive aspergillosis; 11 were IPA and 2 were primary peritoneal infections. Of the 11 patients with IPA, 7 developed neutropenia during hospitalization, and the remaining four were receiving immunosuppressive agents. Ten patients with IPA died; one liver transplantation patient without neutropenia survived after treatment with amphotericin B, itraconazole, and a pulmonary lobectomy. Six patients developed disseminated disease, with the heart the most common extrapulmonary site identified (four patients). These cases demonstrate that IPA caused by A. terreus rapidly progresses in immunocompromised patients receiving amphotericin B and illustrate the need for sensitive diagnostic tests and more effective antifungal agents.


Transplantation | 1993

Frozen section evaluation of donor livers before transplantation

Rodney S. Markin; James L. Wisecarver; Stanley J. Radio; Stratta Rj; Alan N. Langnas; Kathryn Hirst; Byers W. Shaw

Frozen section examination was performed on 385 donor livers before transplantation. Exclusion criteria were applied to the donor livers examined to exclude potentially dysfunctional livers. The exclusion criteria included the following: severe macrovesicular steatosis, ischemic necrosis, prominent chronic portal inflammation, prominent periductular fibrosis, granulomatous inflammation, bridging fibrosis, and malignancy. Twenty-seven of the 385 donor livers examined were excluded before transplantation. The following histologic features were present in the excluded livers: severe steatosis (22), ischemic necrosis (2), portal inflammation (1), and periductular fibrosis (2). Steatosis was present in 51 of the 385 (13.25%) organs examined, including 22 of the donor organs excluded before transplantation. Twenty-nine livers with mild to moderate steatosis were implanted into size and blood type-matched recipients. Indicators of allograft function (prothrombin time and bilirubin) and damage (aspartate aminotransferase and alanine aminotransferase) were measured daily for the first 10 days after transplant. There was no statistically significant difference between the group of nonfat livers and donor livers containing mild steatosis. Statistically significant higher posttransplant serum alanine aminotransferase and prothrombin time levels were present in the patients with livers implanted with mild versus moderate steatosis. The 1-year survival rate for patients receiving fatty versus nonfatty donor livers was not statistically different (Kaplan-Meier, P=0.592). No significant differences were found in the clinical and laboratory characteristics of donors whose organs were implanted compared with the clinical and laboratory characteristics of donors whose organs were excluded. The primary non-function rate after applying the exclusion criteria was 1.4%, which is a significant decrease compared with our primary nonfunction rate of 8.5% before using frozen section examination. Frozen section examination is useful in excluding donor organs which may become dysfunctional after transplantation.


American Journal of Transplantation | 2015

Intestinal transplant registry report: global activity and trends.

David R. Grant; Kareem Abu-Elmagd; George V. Mazariegos; R. Vianna; Alan N. Langnas; R. Mangus; Douglas G. Farmer; F. Lacaille; Kishore Iyer; Thomas M. Fishbein

The Registry has gathered information on intestine transplantation (IT) since 1985. During this time, individual centers have reported progress but small case volumes potentially limit the generalizability of this information. The present study was undertaken to examine recent global IT activity. Activity was assessed with descriptive statistics, Kaplan–Meier survival curves and a multiple variable analysis. Eighty‐two programs reported 2887 transplants in 2699 patients. Regional practices and outcomes are now similar worldwide. Current actuarial patient survival rates are 76%, 56% and 43% at 1, 5 and 10 years, respectively. Rates of graft loss beyond 1 year have not improved. Grafts that included a colon segment had better function. Waiting at home for IT, the use of induction immune‐suppression therapy, inclusion of a liver component and maintenance therapy with rapamycin were associated with better graft survival. Outcomes of IT have modestly improved over the past decade. Case volumes have recently declined. Identifying the root reasons for late graft loss is difficult due to the low case volumes at most centers. The high participation rate in the Registry provides unique opportunities to study these issues.


Annals of Surgery | 2007

Comparison of intestinal lengthening procedures for patients with short bowel syndrome.

Debra Sudan; Jon S. Thompson; Jean F. Botha; Wendy J. Grant; Dean L. Antonson; Steve Raynor; Alan N. Langnas

Objective:Review the clinical results of 24 years of intestinal lengthening procedures at one institution. Methods:Retrospective review of a single center experience comparing the outcome of 2 intestinal lengthening procedures (Bianchi and serial transverse enteroplasty [STEP]) in terms of survival, total parenteral nutrition (TPN) weaning, and complications. Results:Sixty-four patients, including 14 adults, underwent 43 Bianchi and 34 STEP procedures between 1982 and 2007. Three patients had prior isolated liver transplants. The median (range) remnant bowel length before first lengthening was 45 (11-150) cm overall; (Bianchi = 44 cm, STEP = 45 cm) and 68 (20-250) cm after lengthening; (Bianchi = 68 cm, STEP = 65 cm). Actual survival is 91% overall (Bianchi 88%, STEP 95%) with median follow-up of 3.8 years (Bianchi = 5.9 years, STEP = 1.7 years). Average enteral caloric intake in pediatric patients was 15 kcal/kg before lengthening and 85 kcal/kg at 1 year after lengthening. Sixty-nine percent of patients are off TPN at most recent follow-up, including 8 who were weaned from TPN after intestinal transplantation. Liver disease (when present) was reversed in 80%. Surgical complications occurred in 10%, more commonly requiring reoperation after Bianchi than STEP. Intestinal transplantation salvage was required in 14% at a median of 2.9 years (range = 8 months to 20.7 years) after lengthening. Conclusions:Surgical lengthening with both Bianchi and STEP procedures results in improvement in enteral nutrition, reverses complications of TPN and avoids intestinal transplantation in the majority with few surgical complications. Intestinal transplantation can salvage most patients who later develop life-threatening complications or fail to wean TPN.


Transplantation | 1991

Hepatic Allograft Rescue Following Arterial Thrombosis: Role Of Urgent Revascularization

Alan N. Langnas; W. Marujo; R. J. Stratta; R. P. Wood; Shujun Li; B. W. Shaw

Hepatic artery thrombosis is a continuing source of morbidity and mortality following orthotopic liver transplantation. The cornerstone of therapy has been urgent retransplantation that is limited by organ availability. For this reason we developed a policy of urgent revascularization for allograft rescue. Hepatic artery thrombosis developed following 15 transplants of which 11 underwent urgent rearterialization. The diagnosis was made a mean of 4.8 days (range 1-10) following transplantation. Duplex ultrasonography was diagnostic in all patients and confirmed by angiography in 4 (36%). Three patients with hepatic artery thrombosis were identified following screening ultrasonography and were clinically unsuspected. Upon reexploration, a specific technical reason for hepatic artery was found in 4 patients (36%). Twelve arterial revascularization procedures were performed in 11 patients including: thrombectomy alone (n = 4); revision of anastomosis with thrombectomy (n = 5); and thrombectomy with placement of vascular conduit (n = 3). Following revascularization, 8 patients maintained hepatic artery patency. Three patients eventually required retransplantation secondary to biliary sepsis. Biliary tract complications developed in 6 patients, at a mean of 23 days following revascularization and included: breakdown of the biliary anastomosis (n = 4); stricture (n = 1); and sludge formation (n = 1). The overall graft and patient survival are 74% and 82% respectively, with a mean follow-up of 6.8 months. Hepatic allograft rescue with the use of urgent revascularization following hepatic artery thrombosis appears to be an effective means of either avoiding retransplantation or providing a bridge until a suitable donor becomes available.


American Journal of Transplantation | 2006

Inflammatory Bowel Disease After Liver Transplantation: Risk Factors for Recurrence and De Novo Disease

R. C. Verdonk; Gerard Dijkstra; Elizabeth B. Haagsma; V. K. Shostrom; A. P. van den Berg; Jan H. Kleibeuker; Alan N. Langnas; Debra Sudan

Inflammatory bowel disease (IBD) is associated with primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) and can recur or develop de novo after orthotopic liver transplantation (OLT). The aim of this study was to investigate the incidence and severity of IBD after liver transplantation and to perform a multivariate analysis for possible risk factors. In this retrospective study, 91 patients transplanted for PSC or AIH, without prior colectomy, were included. Sixty patients were transplanted for PSC, 31 for AIH. IBD activity before and after OLT and other possible risk factors were analysed in a multivariate model. Forty‐nine patients (54%) had IBD before OLT. Forty patients (44%) had active IBD after transplantation: recurrence in 32 and de novo in 8. Cumulative risk for IBD after OLT was 15, 39 and 54% after 1, 5 and 10 years, respectively. In 59% of patients with IBD prior to OLT the disease was more active after transplantation. Risk factors for recurrent disease were: symptoms at time of OLT, short interval of IBD before OLT and use of tacrolimus. 5‐aminosalicylates were protective. A cytomegalovirus positive donor/negative recipient combination increased the risk for de novo IBD.

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Byers W. Shaw

University of Nebraska Medical Center

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Wendy J. Grant

University of Nebraska Medical Center

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Ira J. Fox

University of Nebraska Medical Center

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Stratta Rj

University of Nebraska Medical Center

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Jean F. Botha

University of the Witwatersrand

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Simon Horslen

University of Washington

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David F. Mercer

University of Nebraska Medical Center

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Jon A. Vanderhoof

Boston Children's Hospital

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