Isolated Donor Specific Alloantibody-Mediated Rejection after ABO Compatible Liver Transplantation

Antibody-mediated rejection (AMR) after liver transplantation is recognized in ABO incompatible and xeno-transplantation, but its role after ABO compatible liver transplantation is controversial. We report a case of ABO compatible liver transplantation that demonstrated clinical, serological and histological signs of AMR without evidence of concurrent acute cellular rejection. AMR with persistently high titers of circulating donor specific antibodies resulted in graft injury with initial centrilobular hepatocyte necrosis, fibroedematous portal expansion mimicking biliary tract outflow obstruction, ultimately resulting in extensive bridging fibrosis. Immunofluorescence microscopy demonstrated persistent, diffuse linear C4d deposits along sinusoids and central veins. Despite intense therapeutic intervention including plasmapheresis, IVIG and rituximab, AMR led to graft failure. We present evidence that an antibody-mediated alloresponse to an ABO compatible liver graft can cause significant graft injury independent of acute cellular rejection. AMR shows distinct histologic changes including a characteristic staining profile for C4d.     

Costimulation and Autoimmune Diabetes in BB Rats

Costimulatory signals regulate T-cell activation. To investigate the role of costimulation in autoimmunity and transplantation, we studied the BB rat model of type 1 diabetes. Diabetes-prone BB (BBDP) rats spontaneously develop disease when 55–120 days of age. We observed that two anti-CD28 monoclonal antibodies (mAb) with different functional activities completely prevented diabetes in BBDP rats. Anti-CD154 mAb delayed diabetes, whereas treatment with CTLA4-Ig or anti-CD80 mAb accelerated disease. Anti-CD86 or anti-CD134L mAbs had no effect. Diabetes resistant BB (BBDR) rats are disease-free, but >95% of them develop diabetes after treatment with polyinosinic-polycytidylic acid and an mAb that depletes Treg cells. In the induced BBDR model, anti-CD154 mAb delayed onset of diabetes, whereas CTLA4-Ig, anti-CD134L or either of the anti-CD28 mAbs had little or no effect. In contrast, blockade of the CD134-CD134L pathway was highly effective for preventing autoimmune recurrence against syngeneic islet grafts in diabetic BBDR hosts. Blockade of the CD40-CD154 pathway was also effective, but less so. These data suggest that the effectiveness of costimulation blockade in the treatment of type 1 diabetes is dependent on both the costimulatory pathway targeted and the mechanism of induction, stage, intensity and duration of the pathogenic process.     

Refractory Ascites After Liver Transplantation: An Analysis of 1058 Liver Transplant Patients at a Single Center

A retrospective study of 1058 liver transplant recipients was performed to determine: (i) the incidence, etiology, timing, clinical features and treatment of refractory ascites (RA), (ii) risk factors for RA development, (iii) predictors of RA disappearance, (iv) predictors of survival following RA and (v) the impact of RA on patient survival. Sixty-two patients (5.9%) developed RA and its disappearance occurred in 27/62 cases. Patients having hepatitis C virus (HCV) had a significantly higher hazard rate of developing RA (p < 0.00001). No other baseline characteristic was associated with RA. Cox stepwise regression analysis of the hazard rate of RA disappearance found two significant factors: HCV recurrence as the reason for developing RA implied a poorer outcome (p = 0.006), whereas an unknown reason implied a favorable outcome (p = 0.02). In addition, survival following RA was significantly poorer among patients having bacterial peritonitis or HCV recurrence. Finally, the mortality rate was significantly (nearly 8.6 times) higher in patients following RA development while it was ongoing (p < 0.00001); however, if the RA disappeared, then the additional risk of death also disappeared. This study illustrates the importance of developing an optimal treatment strategy to (i) effectively treat RA if it develops and (ii) prevent hepatitis C recurrence.     

Acute Inflammatory Syndrome Induced by Mycophenolate Mofetil in a Patient Following Kidney Transplantation

Mycophenolate mofetil (MMF) is increasingly used to prevent acute and chronic rejection following kidney transplantation and in autoimmune diseases. Here, we report on a patient after kidney transplantation, who developed an acute inflammatory syndrome characterized by fever and oligoarthritis within 1 week after increasing the MMF dosage. MMF was discontinued resulting in a complete resolution of the syndrome within 48 h. We demonstrated in vitro that the patient's phorbol myristate acetate (PMA-) and formyl Met-Leu-Phe (fMLP-) stimulated polymorphonuclear neutrophils (PMNs) developed increased oxidative burst when incubated with MMF. This report demonstrates that MMF can also induce acute inflammatory syndrome in patients following kidney transplantation and that this syndrome might be due to a paradox, pro-inflammatory reaction of PMNs.     

The Current Role of Calcineurin Inhibitors in Posttransplant Immunosuppression?

It is important to determine when to use and when to avoid calcineurin inhibitors (CNIs). CNIs are associated with kidney dysfunction in some, but not all, transplant recipients. CNI-sparing protocols have their own drug-specific limitations. Two major clinical series suggest the benefit of routine CNI-sparing approaches, but our review suggests weaknesses in both. Ongoing studies are needed to determine which subgroups of recipients will benefit from CNIs.     

Case Report: Second case of a successful pregnancy in maternal isovaleric acidaemia

Summary: A female patient with isovaleric acidaemia had a successful outcome from pregnancy.