I. Justo Alonso

Porcine acellular dermal matrix for delayed abdominal wall closure after pediatric liver transplantation

Children are one of the groups with the highest mortality rate on the waiting list for LT. Primary closure of the abdominal wall is often impossible in the pediatric population, due to a size mismatch between a large graft and a small recipient. We present a retrospective cohort study of six pediatric patients, who underwent delayed abdominal wall closure with a biological mesh after LT, and in whom early closure was impossible. A non‐cross‐linked porcine‐derived acellular dermal matrix (Strattice™ Reconstructive Tissue Matrix; LifeCell Corp, Bridgewater, NJ, USA) was used in all of the cases of the series. After a mean follow‐up of 26 months (21–32 months), all patients were asymptomatic, with a functional abdominal wall after physical examination. Non‐cross‐linked porcine‐derived acellular dermal matrix (Strattice™) is a good alternative for delayed abdominal wall closure after pediatric LT. Randomized controlled trials are necessary to determine the best moment and the best technique for abdominal wall closure.

Histologic Evaluation of Post-implantation Immediate C4d Deposition in 13 Intestinal Grafts: Correlation With Cell-based Crossmatching, Cold Ischemia Time, and Preservation Injury

C4d deposits are predictive of humoral rejection in kidney and heart transplantation. The aim of this study was to identify C4d deposit patterns in intestinal mucosa of the grafts on biopsy specimens obtained immediately after implantation and to detect if it could be a valuable tool to predict humoral or acute rejection. A second objective was to search for a statistically significant relationship between positive C4d deposition and other collected variables. Thirteen immediately post-transplantation mucosal graft biopsy specimens, formalin fixed, underwent immunohistochemical stain for C4d deposits. Diffuse intense staining of capillary endothelium was considered positive and absent, focal or weak stains as negative. Preservation injury grade and cold ischemia times were registered for each case. Donor-specific preformed antibodies were detected by complement dependent cytotoxicity serologic technique (crossmatching). Another 19 endoscopic follow-up biopsy specimens from days 2 to 6 were also evaluated. Statistical studies were made using the index of correlation ρ (Spearmans test). Diffuse intense C4d deposits were observed in 2 grafts, focal and weak in 5, and completely negative in 6. The mean cold ischemia time was 327 ± 101 minutes. Two cases showed diffuse positive deposits, 1 had a positive crossmatch and the cold ischemia time was 360 minutes whereas the other had not preformed antibodies and its cold ischemia time was 475 minutes. Humoral or acute rejection was not observed in follow-up mucosal biopsy specimens. There was no statistically significant relationship between the C4d deposition, cold ischemia time, crossmatching results, and preservation injury degree. In conclusion, C4d deposition was not a helpful tool for diagnosis of humoral rejection and prediction of acute rejection during the early post-transplantation period.

Renal failure associated with intestinal transplantation: our experience in Spain.

BACKGROUND Renal failure (RF) is a frequent complication in non-renal solid organ transplants. In the present study, we analyze our experience with intestinal transplants (ITx). METHODS Between 2004 and 2012, we performed 21 ITx in 19 adult patients. Alemtuzumab was used as an induction agent followed by tacrolimus. Renal function was assessed before ITx and during the perioperative period. RESULTS The main cause for transplants was non-resectable desmoids tumors (33.3%), followed by vascular thrombosis (19%) and others. Medical complications were frequent, especially infectious diseases, which were the most common (51%). Surgical complications were also frequent, but most of them (>50%) were mild but leading to a great number of re-operations and prolonged stays in hospital. Acute rejection is very frequent (66.6%) but mild in more than 70% of the cases. Finally, RF was very frequent (68.4%; 13/19 patients) and accounted for 15.6% of all medical complications. Causes were multiple. One patient is awaiting a kidney transplant, but no other patients need renal replacement therapy at the moment. Ileostomy closure was performed in 5 of 12 patients alive, showing improved renal function in 3 of them. CONCLUSIONS RF is a problem in ITx and is always multifactorial. Increases in hospital stay, higher morbidity and is a cause for hospital readmission. Almost all patients had an impaired renal function when discharged. Immunosuppressants and ileostomy closure as soon as possible might prevent RF.