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Dive into the research topics where Greg J. McKenna is active.

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Featured researches published by Greg J. McKenna.


Liver Transplantation | 2007

Liver retransplantation for primary nonfunction: Analysis of a 20-year single-center experience†

Tadahiro Uemura; Henry B. Randall; Edmund Q. Sanchez; Toru Ikegami; Gomathy Narasimhan; Greg J. McKenna; Srinath Chinnakotla; Marlon F. Levy; Robert M. Goldstein; Goran B. Klintmalm

Initial graft function following liver transplantation is a major determinant of postoperative survival and morbidity. Primary graft nonfunction (PNF) is uncommon; however, it is one of the most serious and life‐threatening conditions in the immediate postoperative period. The risk factors associated with PNF and short‐term outcome have been previously reported, but there are no reports of long‐term follow‐up after retransplant for PNF. At our institution, 52 liver transplants had PNF (2.22%) among 2,341 orthotopic liver transplants in 2,130 patients from 1984 to 2003. PNF occurred more often in the retransplant setting. Female donors, donor age, donor days in the intensive care unit, cold ischemia time, and operating room time were significant factors for PNF. Patient as well as graft survival of retransplant for PNF was not different compared to retransplant for other causes. However, PNF for a second or third transplant did not demonstrate long‐term survival, and hospital mortality was 57%. In conclusion, retransplant for PNF in the initial transplant can achieve relatively good long‐term survival; however, if another transplant is needed in the setting of a second PNF, the third retransplant should probably not be done due to poor expected outcome. Liver Transpl 13:227–233, 2007.


American Journal of Transplantation | 2011

Limiting Hepatitis C Virus Progression in Liver Transplant Recipients Using Sirolimus-Based Immunosuppression

Greg J. McKenna; James F. Trotter; E. Klintmalm; Nicholas Onaca; Richard Ruiz; Linda W. Jennings; Michael A. Neri; J. G. O’Leary; Gary L. Davis; Marlon F. Levy; Robert M. Goldstein; Goran B. Klintmalm

Hepatitis C virus (HCV) causes progressive liver fibrosis in liver transplant recipients and is the principal cause of long‐term allograft failure. The antifibrotic effects of sirolimus are seen in animal models but have not been described in liver transplant recipients. We reviewed 1274 liver recipients from 2002 to 2010 and identified a cohort of HCV recipients exposed to sirolimus as primary immunosuppression (SRL Cohort) and an HCV Control Group of recipients who had never received sirolimus. Yearly protocol biopsies were done recording fibrosis stage (METAVIR score) with biopsy compliance of >80% at both year one and two. In an intent‐to‐treat analysis, the SRL Cohort had significantly less advanced fibrosis (stage ≥2) compared to the HCV Control Group at year one (15.3% vs. 36.2%, p < 0.0001) and year two (30.1% vs. 50.5%, p = 0.001). Because sirolimus is sometimes discontinued for side effects, the SRL Cohort was subgroup stratified for sirolimus duration, showing progressively less fibrosis with longer sirolimus duration. Multivariate analysis demonstrated sirolimus as an independent predictor of minimal fibrosis at year one, and year two. This is the first study among liver transplant recipients with recurrent HCV to describe the positive impact of sirolimus in respect of reduced fibrosis extent and rate of progression.


Liver Transplantation | 2007

Hepatorenal syndrome: A proposal for kidney after liver transplantation (KALT)

Richard Ruiz; Yousri M. Barri; Linda W. Jennings; Srinath Chinnakotla; Robert M. Goldstein; Marlon F. Levy; Greg J. McKenna; Henry B. Randall; Edmund Q. Sanchez; Goran B. Klintmalm

Hepatorenal syndrome (HRS) is a well‐recognized complication of end‐stage liver disease. Once thought to be a reversible condition with liver transplantation (LT) alone, HRS may directly contribute to the requirement for long‐term dialysis posttransplant. As a result, discussion has now focused on whether or when a kidney allograft should be considered for these patients. Using the International Ascites Club guidelines with a pretransplant serum creatinine (SCr) >2.0 mg/dL to define HRS, 130 patients undergoing LT over a 10‐yr period were identified, for an overall incidence of 9%. Patient survival rates at 1, 3, and 5 yr were 74%, and 68%, and 62%, respectively. Survival was significantly worse when compared to non‐HRS patients undergoing LT over the same study period (P = 0.0001). For patients presenting with type 2 HRS, 7 patients (6%) developed irreversible kidney failure posttransplant compared to 0.34% in the non‐HRS population (P < 0.0001). Five of these patients died within 1 yr with a median survival time of 139 days. Combined liver and kidney transplantation (CLKT) for patients with HRS is not recommended. However, an improvement in outcome can be accomplished by addressing those patients who require dialysis greater than 60 days posttransplant. We propose a role for kidney after liver transplantation (KALT) in select HRS patients. Liver Transpl 13:838–843, 2007.


Clinical Transplantation | 2008

Late acute rejection after liver transplantation impacts patient survival.

Tadahiro Uemura; Toru Ikegami; Edmund Q. Sanchez; Linda W. Jennings; Gomathy Narasimhan; Greg J. McKenna; Henry B. Randall; Srinath Chinnakotla; Marlon F. Levy; Robert M. Goldstein; Goran B. Klintmalm

Abstract:  Hepatic allograft rejection still remains an important problem following liver transplantation. Early acute rejection, occurring within three months of transplant, is a common event and usually of lesser significance with respect to prognosis than other non‐immune‐related post‐transplant morbidities. However, little is known about late acute rejection (LAR) including factors affecting its occurrence and long‐term outcome. In this study, we analyzed LAR including the incidence, clinical risk factors, patient survival, and graft survival. LAR was defined as acute cellular rejection later than six months after liver transplant. Adult patients who had a minimum of 24 months of graft survival were included in this study. A total of 1604 case records of consecutive adult patients (over age 18 yr) who underwent liver transplant between 1985 and 2003 were reviewed. Of the 1604 patients, 305 (19.0%) developed LAR. Patients with primary diagnoses of autoimmune hepatitis, primary biliary cirrhosis, and primary sclerosing cholangitis had higher incidences of LAR, while patients with metabolic disease and retransplant had lower incidence of LAR (p = 0.0024). The LAR group had more female and younger recipients than the no LAR group (p = 0.0026, p = 0.0131, respectively). Patient survival as well as graft survival were significantly lower in the LAR group (p = 0.0083, p = 0.0075, respectively). PTLD was the only significant independent predictor of late rejection. The careful management and treatment of PTLD, especially immunosuppressive management, is important to prevent LAR, which is related to poorer patient survival.


Liver Transplantation | 2012

Implications of a positive crossmatch in liver transplantation: A 20-year review

Richard Ruiz; Koji Tomiyama; Jeffrey Campsen; Robert M. Goldstein; Marlon F. Levy; Greg J. McKenna; Nicholas Onaca; Brian M. Susskind; Glenn W. Tillery; Goran B. Klintmalm

Whether a positive crossmatch result has any relevance to liver transplantation (LT) outcomes remains controversial. We assessed the impact of a positive crossmatch result on patient and graft survival and posttransplant complications. During a 20‐year period, 2723 LT procedures with crossmatch results were identified: 2479 primary transplants and 244 retransplants. The rates of positive B cell and T cell crossmatches were 10.1% and 7.4%, respectively, for primary transplants and 14.6% and 6.4%, respectively, for retransplants (P = 0.049 for a B cell crossmatch). Across all primary transplants, females (P < 0.001) and patients with autoimmune hepatitis (P < 0.001) had greater frequencies of positive crossmatches. There was no effect from race or age. For both primary transplants and retransplants, patient survival and graft survival were not affected by the presence of a positive crossmatch. With respect to posttransplant complications, there were no differences in rejection episodes (hyperacute, acute, or chronic) or technical complications (biliary and vascular) between negative and positive crossmatch groups. However, there were significant differences in the pathological findings of preservation injury (PI) on liver biopsy samples taken at the time of transplantation and within the first week of transplantation (P = 0.003 for B cells and P = 0.03 for T cells). In summary, a positive crossmatch had no significant impact on patient survival or graft outcomes. However, there was a significantly higher incidence of PI in primary LT recipients with a positive crossmatch. This finding is important for a broader understanding of PI, which may include a significant immunological component. Liver Transpl 18:455–460, 2012.


Transplantation | 2010

Predicting renal failure after liver transplantation from measured glomerular filtration rate: review of up to 15 years of follow-up.

Edmund Q. Sanchez; Larry Melton; Srinath Chinnakotla; Henry B. Randall; Greg J. McKenna; Richard Ruiz; Nicholas Onaca; Marlon F. Levy; Robert M. Goldstein; Goran B. Klintmalm

Background. The immunosuppressive medications that have contributed greatly to the success of liver transplantation are also associated with posttransplant renal dysfunction. We reviewed measured glomerular filtration rate (GFR) data from patients who underwent transplantation more than 10 years ago to assess whether results from specific time points can predict renal failure. Methods. The GFR data were obtained at initial evaluation (IE), at month 3, and at years 1, 2, 5, 10, and 15. Two groupings were compared, one based on GFR at IE and the other at month 3. Patients were further stratified into three GFR (mL/min/1.73 m2) groups: G1, GFR more than 80; G2, GFR 60 to 80; and G3, GFR less than 60. Results. A total of 592 liver transplant recipients met the inclusion criteria; 114 had paired GFR data from IE to year 15. Analysis of paired and censored data based on IE GFR showed that 62.2% of G3 patients developed renal failure by year 5; another 6.7% did so by year 10 (P=0.027). The month 3 GFR data showed that 56.3% of G3 patients developed renal failure by year 5; another 15.6% did so by year 10. Surprisingly, 37.0% of G2 patients experienced renal failure by year 5; another 11.1% did so by year 10 (P=0.0024). Conclusions. The month 3 data indicate a slow but steady decline in GFR over years. The lower the initial GFR is after transplant, the sooner renal failure develops. Patients with GFR less than 60 mL/min per 1.73 m2 at month 3 have a higher risk of renal failure; however, those who avoid renal failure seem to maintain renal function long term.


Liver Transplantation | 2008

Twenty years of follow‐up of aortohepatic conduits in liver transplantation

Dmitriy Nikitin; Linda W. Jennings; Tariq Khan; Edmund Q. Sanchez; Srinath Chinnakotla; Henry B. Randall; Greg J. McKenna; Robert M. Goldstein; Marlon F. Levy; Goran B. Klintmalm

Arterial problems remain a formidable challenge in liver transplantation. In many situations, an aortohepatic conduit can provide a solution. No long‐term results (over 5 years) have been reported. This study was designed to assess the impact of aortohepatic conduits on graft survival after liver transplantation and the safety of aortohepatic conduits and to establish the long‐term results (up to 20 years) of aortohepatic conduits. Data from 2346 adult liver transplants were prospectively collected into the computerized database and analyzed. In the majority of cases, arterial conduits were constructed from the donor iliac artery obtained at the liver retrieval. Aortohepatic conduits were required in 149 (6.4%) first transplants. The long‐term graft survival after liver transplantation using aortohepatic conduits was excellent and comparable to that of the control group. The graft survival was 59% with the conduit versus 67% without the conduit at 5 years of follow‐up, 50% versus 52% at 10 years, and 33% versus 35% at 15 years. With up to 20 years of follow‐up, there was no statistically significant difference in graft survival, patient survival, hepatic artery complications, or biliary complications. For the same time period, there was no statistically significant difference in graft survival or patient survival for the retransplants with and without aortohepatic conduits. In conclusion, in experienced hands, aortohepatic conduits can be used safely for liver transplantation with no negative impact on long‐term graft survival, patient survival, hepatic artery complications, or biliary complications. Excellent long‐term results can be obtained. Liver Transpl 14:1486–1490, 2008.


American Journal of Transplantation | 2017

Living Donor Uterus Transplantation: A Single Center's Observations and Lessons Learned From Early Setbacks to Technical Success

Giuliano Testa; E. C. Koon; L. Johannesson; Greg J. McKenna; Tiffany Anthony; Goran B. Klintmalm; R. T. Gunby; Ann Marie Warren; J. M. Putman; G. dePrisco; J. M. Mitchell; K. Wallis; Michael Olausson

Uterus transplantation is a vascularized composite allograft transplantation. It allows women who do not have a uterus to become pregnant and deliver a baby. In this paper, we analyze the first five cases of living donor uterus transplantation performed in the United States. The first three recipients lost their uterus grafts at days 14, 12, and 6, respectively, after transplant. Vascular complications, related to both inflow and outflow problems, were identified as the primary reason for the graft losses. Two recipients, at 6 and 3 mo, respectively, after transplant, have functioning grafts with regular menstrual cycles. Ultimate success will be claimed only after a live birth. This paper is an in‐depth analysis of evaluation, surgical technique, and follow‐up of these five living donor uterus transplants. The lessons learned were instrumental in allowing us to evolve from failure to technical and functional success. We aim to share our conclusions and build on knowledge in the evolving field of uterus transplantation.


Transplantation | 2013

Sirolimus and cardiovascular disease risk in liver transplantation.

Greg J. McKenna; James F. Trotter; E. Klintmalm; Richard Ruiz; Nicholas Onaca; Giuliano Testa; Giovanna Saracino; Marlon F. Levy; Robert M. Goldstein; Goran B. Klintmalm

Background Two adverse effects of sirolimus are hypertriglyceridemia and hypercholesterolemia. These elevated levels often lead clinicians to discontinue the sirolimus from concerns of an increased cardiovascular disease (CVD) risk; however, evidence suggests that sirolimus might be cardioprotective. There are no published reports of sirolimus CVD in liver transplantation. Methods We reviewed all 1812 liver recipients who underwent transplantation from 1998 to 2010, identifying a cohort using sirolimus as part of the initial immunosuppression (SRL Cohort) and a control group of the remaining patients from this period where SRL was never given (Non-SRL Control). A prospectively maintained database identified all episodes of myocardial infarction (MI), congestive heart failure (CHF), abdominal aortic aneurysm (AAA), and cerebrovascular accident and tracked triglyceride, high-density and low-density lipoproteins, and total cholesterol levels. A Framingham Risk Model calculated the predicted 10-year risk of CVD for both groups. Results The SRL Cohort (n=406) is older, more predominantly male, with more pretransplantation hypertension and diabetes and posttransplantation hypertension compared to Non-SRL Controls (n=1005). The SRL Cohort has significantly higher triglyceride, low-density lipoprotein, and cholesterol levels at 6 months and 1 year. There is no difference in MI incidence in the SRL Cohort (1.0% vs. 1.2%) and no difference in AAA, cerebrovascular accident, and CHF. The Framingham Risk Model predicts that the SRL Cohort should have almost double the 10-year risk of CVD compared to the Non-SRL Control (11% vs. 6%). Conclusions Sirolimus causes hypertriglyceridemia and hypercholesterolemia, but it does not increase the incidence of MI or other CVDs. Considering the SRL Cohort has more cardiac risk factors and nearly double 10-year predicted CVD risk, the fact that the CVD incidence is similar suggests that sirolimus is in fact cardioprotective.


Clinical Transplantation | 2005

Successful combined liver and kidney transplant for COACH syndrome and 5-yr follow-up

Tadahiro Uemura; Edmund Q. Sanchez; Toru Ikegami; David L. Watkins; Gomathy Narasimhan; Greg J. McKenna; Srinath Chinnakotla; Sherfield Dawson; Henry B. Randall; Marlon F. Levy; Robert M. Goldstein; Goran B. Klintmalm

Abstract:  The COACH syndrome is a very rare disorder with cerebellar vermis hypoplasia, oligophrenia, ataxia, coloboma, and hepatic fibrosis. Nineteen cases with COACH diagnosis have been reported. Neurologic abnormalities are the first symptoms in most cases. Complications of the hepatopathy [portal hypertension, esophageal varices, and gastrointestinal (GI) bleeding] contribute extensively to the morbidity and lethality in the course of the disease. We describe a 28‐yr‐old female with COACH syndrome resulting in chronic renal and hepatic insufficiency. The patient was found to have significant mental retardation, truncal ataxia, motor abnormality and occulomotor abnormality. She began to develop GI bleeding and encephalopathy because of biopsy‐confirmed cirrhosis. We performed combined liver and kidney transplant after challenging discussion. Her postoperative course was uneventful, and she was discharged on the ninth postoperative day (POD). She has not had any problems at 1, 3 and 5‐yr follow‐up with excellent liver and renal function. This is the first description of successful combined liver and kidney transplant with long‐term follow‐up. The decision for transplant is challenging because COACH syndrome is rare with only descriptive characterization and patients have non‐progressive ataxia and mental retardation. However, our case shows that liver and kidney transplant can be medically successful, and the individuals achieve long‐term success if they have a stable neurological condition and an excellent support system.

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Robert M. Goldstein

Baylor University Medical Center

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Goran B. Klintmalm

Baylor University Medical Center

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Richard Ruiz

Baylor University Medical Center

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Nicholas Onaca

Baylor University Medical Center

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Marlon F. Levy

Baylor University Medical Center

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Henry B. Randall

Baylor University Medical Center

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James F. Trotter

Baylor University Medical Center

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Linda W. Jennings

Baylor University Medical Center

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Edmund Q. Sanchez

Baylor University Medical Center

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