Gero Puhl

Long-term follow-up after recurrence of primary biliary cirrhosis after liver transplantation in 100 patients

Abstract: Orthotopic liver transplantation (OLT) is the only effective curative therapy for end‐stage primary biliary cirrhosis (PBC). Survival after OLT is excellent, although recent data have shown a recurrence rate of PBC of up to 32% after transplantation. The aim of this study is to investigate the course after disease recurrence, particularly with regard to liver function and survival in a long‐term follow‐up. Between April 1989 and April 2003, 1553 liver transplantations were performed in 1415 patients at the Charité, Virchow Clinic. Protocol liver biopsies were taken after one, three, five, seven, 10 and 13 yr. One hundred (7%) patients suffered from histologically proven PBC. Primary immunosuppression consisted of cyclosporine (n=54) or tacrolimus (Tac) (n=46). Immediately after OLT, all patients received ursodeoxycholic acid. Corticosteroids were withdrawn three to six months after OLT. The median age of the 85 women and 15 men was 55 yr (range 25–66 yr). The median follow‐up after liver transplantation was 118 months (range 16–187 months) and after recurrence 30 months (range 4–79 months). Actuarial patient survival after five, 10 and 15 yr was 87, 84 and 82% respectively. Ten patients (10%) died after a median survival time of 32 months. Two of these patients developed organ dysfunction owing to recurrence of PBC. Histological recurrence was found in 14 patients (14%) after a median time of 61 months (range 36–122 months). Patients with Tac immunosuppression developed PBC recurrence more often (p<0.05) and also earlier (p<0.05). Fifty‐seven patients developed an acute rejection and two patients a chronic rejection episode. Liver function did not alter within the first five yr after histologically proven PBC recurrence. Multivariate analysis of the investigated patients showed that the recipients age and Tac immunosuppression were significant risk factors for PBC recurrence. Long‐term follow‐up of up to 15 yr after liver transplantation, owing to PBC, in addition to maintenance of liver function, shows excellent organ and patient survival rates. Although protocol liver biopsies revealed histological recurrence in 14 (14%) patients, only two patients developed graft dysfunction. Tac‐treated patients showed more frequently and also earlier histologically proven PBC recurrence; however, in our population we could not observe an impact on graft dysfunction and patients survival.

MMF and Calcineurin Taper in Recurrent Hepatitis C After Liver Transplantation: Impact on Histological Course

Hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT) is almost universal. The optimal immunosuppression for these patients is still under discussion. We designed a retrospective case‐control study to evaluate the effect of mycophenolate mofetil (MMF) treatment in patients with recurrent hepatitis C.

Initial hepatic microcirculation correlates with early graft function in human orthotopic liver transplantation

Microcirculatory disturbances are an initial causative determinant in hepatic ischemia/reperfusion injury. The aim of this study was to assess sinusoidal perfusion during human liver transplantation using orthogonal polarization spectral imaging and to evaluate the significance of intraoperative microcirculation for early postoperative graft function. Hepatic microcirculation was measured in 27 recipients undergoing full‐size liver transplantation and compared to a group of 32 healthy living‐related liver donors. The microvascular parameters were correlated with postoperative aspartate aminotransferase and bilirubin levels. Hepatic perfusion following liver transplantation was found to be significantly decreased when compared with the control group. Volumetric blood flow within the individual sinusoids increased due to sinusoidal dilatation and enhanced flow velocity. Regression analysis of postoperative aspartate aminotransferase and bilirubin with microvascular parameters revealed significant correlations. The extent of volumetric blood flow increased within the first 30 minutes after reperfusion and showed a significant correlation with postoperative aspartate aminotransferase release and bilirubin elimination. In conclusion, postischemic hepatic microvascular perfusion was analyzed in vivo, demonstrating significant microvascular impairment during liver transplantation. Sinusoidal hyperperfusion appears to confer protection against postischemic liver injury, as given by the correlation with aspartate aminotransferase and bilirubin levels. Thus, these findings may have therapeutic importance with respect to mechanisms mediating postischemic reactive hyperemia. (Liver Transpl 2005;11:555–563.)

In Vivo Imaging of Human Pancreatic Microcirculation and Pancreatic Tissue Injury in Clinical Pancreas Transplantation

Pancreatitis remains to be a major complication following clinical pancreas transplantation. We performed orthogonal polarized spectral (OPS) imaging for direct in vivo visualization and quantification of human pancreatic microcirculation in six healthy donors for living donor liver transplantation and 13 patients undergoing simultaneous pancreas‐kidney transplantation. We further determined the impact of microvascular dysfunction during early reperfusion on pancreatic graft injury. Exocrine and endocrine pancreatic impairment was determined by analysis of serum lipase, amylase and C‐peptide levels. Compared to normal pancreas in liver donors (homogeneous acinar perfusion) functional capillary density (FCD) and capillary red blood flow velocity of reperfused grafts were significantly decreased. Elevated CRP concentrations on day 2 post‐transplant and serum lipase and amylase levels determined on days 4–5 significantly correlated with microvascular dysfunction during the first 30 min of graft reperfusion. Post‐transplant serum C‐peptide also correlated significantly with pancreatic capillary perfusion. OPS imaging allows to intra‐operatively assess physiologic pancreatic microcirculation and to determine microcirculatory impairment during early graft reperfusion. This impairment correlated with the manifestation of post‐transplant dysfunction of both exocrine and endocrine pancreatic tissue. OPS imaging may be used clinically to determine the efficacy of interventions, aiming at attenuating microcirculatory impairment during the acute post‐transplant reperfusion phase.

Influence of donor/recipient HLA‐matching on outcome and recurrence of hepatitis C after liver transplantation

The aim of this study was to analyze the effect of human leukocyte antigen (HLA) matching on outcome, severity of recurrent hepatitis C and risk of rejection in hepatitis C positive patients after liver transplantation (LT). In a retrospective analysis, 165 liver transplants in patients positive for hepatitis C virus (HCV) with complete donor/recipient HLA typing were reviewed for recurrence of HCV and outcome. Follow‐up ranged from 1 to 158 months (median, 74.5 months). Immunosuppression consisted of either cyclosporine‐A‐ or tacrolimus‐based quadruple induction therapy including or an interleukin 2‐receptor antagonist. Protocol liver biopsies were performed after 1, 3, 5, 7, and 10 years and staged according to the Scheuer scoring system. The overall 1‐, 5‐, and 10‐year graft survival figures were 81.8%, 69.11 and 62%, respectively. There was no correlation in the study population between number of HLA mismatches and graft survival. The number of rejection episodes increased significantly in patients with more HLA mismatches (P < 0.05). In contrast to this, the fibrosis progression was significantly faster in patients with 0–5 HLA mismatches compared to patients with a complete HLA mismatch. In conclusion, HLA matching did not influence graft survival in patients after LT for end‐stage HCV infection, however, despite less rejection episodes, the fibrosis progression increased in patients with less HLA mismatches within the first year after LT. Liver Transpl 12:644–651, 2006.

Donor Age Does Not Influence 12-Month Outcome After Orthotopic Liver Transplantation

OBJECTIVE Orthotopic liver transplantation (OLT) is the most effective treatment for patients with end-stage liver disease to date. The discrepancy between the numbers of donor livers and recipients has become a significant problem, resulting in a high patient mortality on the waiting list. Due to this, an expansion of the donor pool is necessary, for example, by accepting donor grafts from elderly donors. The aim of this study was to investigate the outcome after OLT depending on donor age. METHODS We retrospectively evaluated the outcome of 272 full-size cadaveric initial single OLTs within 12 months after OLT. The outcome was analyzed by dividing the collective into four donor age categories: donor age under 50, between 50 and 59, between 60 and 69, and 70 years or above. The outcome after OLT in these patients was retrospectively reviewed by using a prospective database. Patients positive for hepatitis C were excluded from the analysis. RESULTS No increase of initial nonfunction was observed. Furthermore, no significant differences with regard to surgical complications and serum liver parameter were observed between the groups. Neither patient mortality rates nor rejection rates were different between the groups. However, ischemic-type biliary lesion rates increased significantly with donor age over 70 years (P<.05). CONCLUSIONS The acceptance of liver grafts from older donors is a possible alternative to narrow the gap between donated and required organs. Safe use under optimal protocols is necessary to avoid a deterioration of post-OLT results.

24‐h storage of pig livers in UW, HTK, hydroxyethyl starch, and saline solution: is microdialysis an appropriate method for the continuous graft monitoring during preservation?

Recent studies demonstrate the feasibility of microdialysis to monitor metabolism in ischemic livers. Whether these parameters correlate with markers of liver cell integrity in an experimental model using pig livers and different preservation solutions was an aim of this study. Pig livers were flushed with either 4 °C Histidine‐Typtophan‐Ketoglutarate solution (HTK) (Custodiol®), University of Wisconsin solution (ViaSpan®), and hydroxyethyl starch, or 12 °C saline solution. After 24‐h storage, the livers were rinsed with saline to measure liver enzymes and lactate from the effluate. Utilizing microdialysis, intraparenchymal lactate, pyruvate, glucose, and glycerol was monitored. Tissue biopsies were taken for histological examinations. Cold preservation resulted in a decrease of metabolic activity measured by intrahepatic glucose, lactate, and pyruvate levels, as well as lactate in the effluate, independently of the solution used. Of particular interest, glycerol levels partially reflected the extent of hepatocellular damage and liver enzyme release. Glycerol levels partially discriminated preservation of different quality and were in accordance to histological findings and liver enzyme release. Lactate, pyruvate, and glucose levels were not appropriate as markers during cold storage. Whether or not glycerol monitoring could represent an additional and rational complementation to the current practice of macroscopic, microscopic and donor evaluation has to be clarified by further studies.

Die Mikrozirkulation des humanen Pankreas in der frühen Reperfusion nach Pankreastransplantation

Introduction: There is abundant experimental evidence to indicate that microcirculatory deteriorations developing in response to post-ischemic reperfusion are key determinants for manifestation of graft pancreatitis and subsequent exo- and endocrine organ dysfunction. Using non-invasive orthogonal spectral (OPS) imaging this study was aimed to intraoperatively visualize and quantitatively assess pancreatic microcirculation in patients undergoing simultaneous pancreas/kidney transplantation. Methods: In nine patients undergoing simultaneous pancreas/kidney transplantation microcirculation of the pancreas graft was analyzed at 5 and 30 min following graft reperfusion using OPS-imaging. Pancreatic microcirculatory parameters of six healthy individuals undergoing donor operation for living-related liver transplantation served as controls. Assessment of microcirculatory parameters included capillary diameter, functional capillary density (FCD) and red blood cell velocity (VRBCV). Based on these parameters the heterogeneity index (HI) and volumetric capillary blood flow (vCBF) were calculated. Results: During early graft reperfusion capillary perfusion was significantly impaired as an increased intercapillary distance, reduced capillary blood flow and microvascular thrombosis in terms of post-ischemic ‘no reflow’ were characteristically observed. The FCD and RBCV were found constantly decreased throughout the entire study period when compared to controls. Furthermore, capillary diameter were significantly increased following graft reperfusion. Calculation of vCBF and HI displayed only a slight increase most pronounced at 30 min of reperfusion. Conclusion: Intraoperative OPS-imaging permits for the first time to non-invasively visualize and quantitatively assess human pancreas microcirculation. It further allows in vivo estimation of conservation- and ischemia/reperfusion-associated microvascular injury during early reperfusion period. Early microvascular response to pancreas transplantation in humans is characterized by persistently decreased acinar perfusion including capillary dilation and nutritive dysfunction. Recognition of initial microcirculatory disturbances may have therapeutic implications for preventing ischemia/ reperfusion-induced exo- and endocrine graft dysfunction and should allow a correlation to the individual clinical course.

Einfluss der portalvenösen und simultanen Transplantatreperfusion auf die Mikrozirkulation nach Leber-Lebendtransplantation

In clinical liver transplantation portal reperfusion is preferentially performed before arterial reconstruction to reduce the anhepatic period. Experimental and clinical data have raised doubts upon this concept. However, visualization and quantitative analysis of sinusoidal perfusion comparing simultaneous arterial/portal with portal/delayed arterialization reperfusion are missing up to now. Therefore, the present study aimed to analyze sinusoidal perfusion during sequential and simultaneous graft reperfusion in patients undergoing living-donor liver transplantation (n = 21). Microvascular observation was performed using the orthogonal polarization spectral (OPS)-imaging technique. Baseline microcirculation was assessed in donor livers directly following laparotomy. In group 1 (n = 14) the reperfusion was performed sequentially compared to group 2 (n = 7) with simultaneous arterial/portal reperfusion. Sinusoidal perfusion was analyzed 5 and 30 min following rearterialization. The mean cold ischemia time was 72 ± 33 min in group 1 and 100 ± 36 min in group 2 (p = 0.1). The mean portal clamping time was 41 ± 16 min in group 1 and 57 ± 11 min in group 2 (p = 0.07). Quantification of the microcirculatory parameters was performed off-line by using a computer-assisted image analysis system as were the sinusoidal diameter (D), red blood cell velocity (RBCV), sinusoidal volumetric blood flow (BVs), functional sinusoidal density (FSD), and inter-sinusoidal distance (ISD). Deteriorations of sinusoidal perfusion were significantly less pronounced in group 2. Typically, manifestation of red blood cell sludging and sinusoidal perfusion stasis was observed in group 1. In group 2 the FSD was significantly increased compared to group 1. In contrast, the RBCV, D, and BVs in group 1 were significantly higher compared to group 2, indicating a reactive post-ischemic hyperemia. Delayed arterialization, i.e. portal reperfusion may cause rapid graft rewarming without adequate oxygenation, resulting in warm ischemia, which may lead to the more pronounced post-ischemic reaction. The lack of vis a tergo during initial reperfusion, when sinusoids have to be cleared of hepatocellular blebs and endothelial cells detached during cold storage, may be responsible for sinusoidal no-reflow phenomenon, particularly in areas receiving predominantly arterial inflow and could explain the improvement of FSD following simultaneous reperfusion.