Tomasz Kozlowski

Liver allograft antibody‐mediated rejection with demonstration of sinusoidal C4d staining and circulating donor‐specific antibodies

The importance of antibody‐mediated rejection (AMR) in ABO‐compatible liver transplantation is controversial. Here we report a prospective series of liver recipients with a preoperative positive crossmatch. To establish the diagnosis of AMR in liver recipients, the criteria described for kidney allografts were adopted. In approximately 10% of 197 liver transplants, we observed a positive T and B cell flow crossmatch before transplantation. Fifteen of 19 patients converted to negative crossmatches early after transplantation and displayed normal liver function while they were on routine immunosuppression. Four patients maintained positive crossmatches. Three of the 4 met the criteria for AMR and showed evidence of graft dysfunction, the presence of donor‐specific antibodies (DSAs), morphological tissue destruction with positive C4d linear staining on the graft sinusoidal endothelium, and improved function with attempts to eliminate DSAs. A persistently positive crossmatch after liver transplantation may lead to early, severe AMR and liver failure. C4d staining in the liver sinusoidal endothelium should alert one to the possibility of AMR. In our experience, patients with a positive crossmatch should have it repeated at 2 weeks and, if it is positive, again at 3 to 5 weeks. Recipients with an unknown preoperative crossmatch who develop early cholestasis of unclear etiology should be crossmatched or tested for the presence of DSAs to evaluate for AMR. Liver Transpl, 2011.

Sinusoidal C4d deposits in liver allografts indicate an antibody-mediated response: Diagnostic considerations in the evaluation of liver allografts†

There is a paucity of data concerning the correlation of complement component 4d (C4d) staining in liver allografts and antibody‐mediated rejection. Data about the location and character of C4d deposits in native and allograft liver tissues are inconsistent. We performed C4d immunofluorescence (IF) on 141 fresh‐frozen liver allograft biopsy samples and native livers, documented the pattern of C4d IF staining, and correlated the findings with the presence of donor‐specific alloantibodies (DSAs). A linear/granular sinusoidal pattern of C4d IF was noted in 18 of 28 biopsy samples obtained after transplantation from patients with positive crossmatch and detectable donor‐specific alloantibody (pos‐XM/DSA) findings. None of the 59 tested biopsy samples from patients with negative crossmatch and detectable donor‐specific alloantibody (neg‐XM/DSA) findings were C4d‐positive (P < 0.001). No significant association was found between pos‐XM/DSA and C4d IF staining in other nonsinusoidal liver compartments. To compare the results of sinusoidal C4d staining with IF and 2 immunohistochemistry (IHC) techniques, C4d IHC was performed on 19 liver allograft biopsy samples in which a sinusoidal pattern of C4d IF had been noted. Sinusoidal C4d IHC findings were negative for 17 of the 19 biopsy samples; 2 showed weak and focal staining, and both patients had pos‐XM/DSA findings. Portal vein endothelium staining was present in only 1 IF‐stained biopsy sample (pos‐XM/DSA) but in 11 IHC‐stained biopsy samples (2 of the 11 samples had neg‐XM/DSA findings). We conclude that sinusoidal C4d deposits detected by IF in frozen tissue samples from liver allograft recipients correlate with the presence of DSAs and an antibody‐mediated alloresponse. These observations are similar to findings reported for other solid organ transplants and can provide relevant information for patient management. Further validation of IHC techniques for C4d detection in liver allograft tissue is required. Liver Transpl 18:641–658, 2012.

Diagnostic significance of peritubular capillary basement membrane multilaminations in kidney allografts: Old concepts revisited

Background Injury to peritubular capillaries and capillary basement membrane multilamination (PTCL) is a hallmark of antibody-mediated chronic renal allograft rejection. However, the predictive diagnostic value of PTCL is incompletely studied. Methods We analyzed the diagnostic significance of PTCL and propose diagnostic strategies. We evaluated 360 diagnostic native and 187 transplant kidney specimens by electron microscopy (terminology: PTCL-C, severe; PTCL subgroup C3, very severe multilamination; see Materials and Methods for definitions). Results PTCL was not pathognomonic for any specific disease. PTCL-C/C3 was rare in native kidneys (C, 6%; C3, 1%), associated mainly with late thrombotic microangiopathy (C: 78%; C3: 11% of cases). In allografts, PTCL-C/C3 was significantly more common, especially in specimens more than 24 months after transplantation (C, 47%; C3, 31%). PTCL-C/C3 was found in acute (C, 20%; C3, 7%) and chronic T-cell rejection (C, 67%; C3, 29%), calcineurin inhibitor toxicity (C, 36%; C3, 18%), or C4d+ specimens (C, 61%; C3, 50%) with odds ratios between 4 and 36. PTCL-C3 was more predominant in cases with antibody-mediated injury. Highest odds ratios (81–117) for PTCL-C/C3 were noted in combined injuries, that is, mixed chronic T-cell and concurrent chronic antibody–mediated rejection. Positive predictive values of PTCL-C and C3 are the following: all rejection types, 89% and 93%; all Banff chronic rejection types, 69% and 71%; and chronic presumptive antibody rejection, 37% and 49%, respectively. Corresponding negative predictive values of C and C3 for different Banff rejection categories are between 50% and 94%. Conclusions The presence of PTCL-C3 is a helpful adjunct finding to diagnose rejection-induced tissue injury but cannot precisely predict the Banff rejection category. Conversely, the absence of PTCL-C3 is helpful in excluding chronic, Banff category II antibody–mediated rejection.

Limitations of Rituximab/IVIg desensitization protocol in kidney transplantation; Is this better than a tincture of time?

BACKGROUNDnA plasmapheresis-free protocol for desensitization of donor kidney transplant candidates with high Calculated Panel Reactive Antibody (CPRA) was initiated at our center. The protocol was adopted from previously published work by Vo, Jordan et al.nnnMATERIAL/METHODSnFive patients with CPRA of 94 ± 18%, awaiting kidney transplant from living or deceased donors received rituximab (1 g × 2 doses) and intravenous immunoglobulin (IVIG 2 g/kg × 2 doses) without plasmapheresis. Levels of donor specific antibodies (DSA) and T/B cell crossmatches were followed using solid phase flow cytometry.nnnRESULTSnThree out of 5 patients were sensitized only to Class II HLA antigens. All patients had very high levels of alloantibodies before initiation of the treatment. All of the candidates initially demonstrated reduced levels of HLA antibody, but statistical significance was only obtained in one patient Class II antibody and in another only for Class I. Depletion was transient with observed antibody rebound. Rituximab effectively depleted CD20 cells in peripheral blood. None of the patients were transplanted due to persistently high levels of antibody and strong positive flow cytometry crossmatches. Under this protocol, reduction of HLA antibodies in patients with high levels was insufficient.nnnCONCLUSIONSnHighly allo-sensitized patients with a CPRA above 85% may not benefit from a combination of rituximab-IVIG alone. The previously published protocol does not help all patients achieve an acceptable crossmatch. An individualized approach to the treatment of highly sensitized patients is still required.

The Influence of Nonalcoholic Fatty Liver Disease and Its Associated Comorbidities on Liver Transplant Outcomes

Goals To define the influence of nonalcoholic fatty liver disease (NAFLD) and its associated comorbidities on liver transplant outcomes. Background NAFLD cirrhosis is an increasing indication for transplant. The transplant outcomes of NAFLD patients with metabolic syndrome comorbidities remain unclear. Study We examined a single center, retrospective cohort between 2004 and 2007 to determine transplant mortality for NAFLD and non-NAFLD patients accounting for the possible independent effects of diabetes, hypertension, obesity, and hyperlipidemia. The primary outcomes were 30-day, 1-year, and 3-year all-cause mortality. Cox proportional hazard ratios were determined controlling for various recipient and donor covariates. Results In our study, of 118 liver transplants, 18% were performed for NAFLD cirrhosis. Adjusted hazard ratios for death for NAFLD compared with non-NAFLD patients at 30 days, 1 year, and 3 years were 8.96 (1.06, 75.8), 1.49 (0.38, 5.81), and 1.05 (0.29, 3.78), respectively. Compared with nondiabetic patients, diabetic patients had hazard ratios at 30 days, 1 year, and 3 years of 2.02 (0.31, 12.9), 2.82 (0.94, 8.47), 3.58 (1.32, 9.71), respectively. Obesity, hypertension, and hyperlipidemia did not have a significant impact on posttransplant mortality. Conclusions We conclude that NAFLD increases 30-day transplant mortality whereas diabetes increases 3-year mortality. Future work should determine the strategies to decrease perioperative mortality among NAFLD patients and ways to improve long-term transplant survival among diabetics.

Long‐term survival after 67 hours of anhepatic state due to primary liver allograft nonfunction

Primary liver allograft nonfunction immediately after transplantation poses a life‐threatening situation for the recipient. Emergency retransplantation may not be immediately possible due to organ unavailability. Total hepatectomy with temporary portacaval shunt has been described as a bridge to retransplantation when the presence of the graft appears to be harming the recipient. Case reports of retransplantation after total hepatectomy with anhepatic times greater than 48 hours routinely describe poor outcomes. We present a case with excellent patient outcome after 95 hours of clinical anhepatic state, including 67 hours of anatomical anhepatic time, because of primary liver allograft nonfunction. This case report documents the longest anhepatic time with subsequent successful transplant to date. Liver Transpl 16:1428–1433, 2010.

Salvage Treatment of Mucormycosis Post-Liver Transplant With Posaconazole During Sirolimus Maintenance Immunosuppression

We describe the first successful case of posaconazole salvage therapy for mucormycosis with concomitant sirolimus (SRL) maintenance immunosuppression following liver transplantation, despite black box drug interaction following intolerance to first-line tacrolimus and amphotericin due to nephrotoxicity and neurotoxicity. This case describes a 55-year-old female who developed rhinocerebral mucormycosis 108 days after liver transplantation. After 3 months of posaconazole therapy, the patient remains free of disease at 3 years posttransplant. This case report illustrates successful resolution of mucormycosis without SRL toxicity to resolve nephrotoxicity of long-term amphotericin on top of already nephrotoxic immunosuppression. With higher bioavailability of recently FDA-approved posaconazole delayed release tablets, this azole may be a therapeutic option for transplant patients who need to remain on CYP3A4-metabolized immunosuppressive agents.

Focal Fat Masquerading as Malignancy in the Liver Graft of a Post-Transplant Patient

Background and AimsLiver failure from non-alcoholic fatty liver disease (NAFLD) is an increasing indication for liver transplant and recurrence of fatty liver in transplanted grafts has been documented. Herein is described an atypical recurrence of steatosis as a de novo focal fatty lesion that mimicked a more ominous cancerous lesion. This presentation of recurrent NAFLD has not previously been described in the literature.MethodsChart review.ResultsBiopsy of an atypical lesion was found to be focal fat with surrounding steatohepatitis.ConclusionsNon-alcoholic fatty liver disease may recur after liver transplant and manifest as a focal fatty lesion. It is important to catalogue the atypical presentations of the increasingly common NAFLD developing in transplanted livers.

Journey of the Surgeon

I was born, raised, and educated in Warsaw, Poland. I finished my 6-year medical school at the age of 24. My first workplace was my own medical alma mater. Two years prior to being granted official employment in the Department of Surgery, I was an anatomy tutor for medical students. I tutored during the day and volunteered as a young surgeon in training afterhours.

C1q Test for Identification of Sensitized Liver Recipients at Risk of Early Acute Antibody-Mediated Rejection

BACKGROUND The majority of liver recipients transplanted with positive crossmatch have a post-transplant course free of acute antibody-mediated rejection (AMR). However, 10% of sensitized recipients develop early severe AMR. There is no clear strategy that would allow for predicting the postoperative course in sensitized liver recipients. One of the possible factors contributing to the dichotomous course in sensitized recipients may be the complement-binding characteristics of the donor-specific antibodies (DSA). MATERIAL AND METHODS We tested sera of sensitized recipients with DSA at the time of transplant, diagnosed with severe AMR or AMR-free for C1q reactivity and strength of mean fluorescence intensity (MFI) in single-antigen beads (SAB) assay. RESULTS Both groups tested positive for DSA C1q binding and DSA-SAB. Recipients with early AMR had significantly stronger DSA MFI in the C1q assay (P<.0001). AMR was observed in patients with very high DSA C1q MFI (22681±8841 vs. the no-AMR group 7954±2061). In SAB assay, DSA MFI strength differences were equivocal (P=0.31). CONCLUSIONS The C1q test is a supportive adjunct in identifying patients at risk of postoperative acute AMR and selects an AMR-free course with 100% negative predictive value despite the presence of DSA.