ABO-Incompatible Liver Transplantation in Acute Liver Failure: A Single Portuguese Center Study

INTRODUCTION: ABO-incompatible liver transplantation (ABOi LT) is considered to be a rescue option in emergency transplantation. Herein, we have reported our experience with ABOi LT including long-term survival and major complications in these situations. PATIENT AND METHODS: ABOi LT was performed in cases of severe hepatic failure with imminent death. The standard immunosuppression consisted of basiliximab, corticosteroids, tacrolimus, and mycophenolate mofetil. Pretransplantation patients with anti-ABO titers above 16 underwent plasmapheresis. If the titer was above 128, intravenous immunoglobulin (IVIG) was added at the end of plasmapheresis. The therapeutic approach was based on the clinical situation, hepatic function, and titer evolution. A rapid increase in titer required five consecutive plasmapheresis sessions followed by administration of IVIG, and at the end of the fifth session, rituximab. RESULTS: From January 2009 to July 2012, 10 patients, including 4 men and 6 women of mean age 47.8 years (range, 29 to 64 years), underwent ABOi LT. At a mean follow-up of 19.6 months (range, 2 days to 39 months), 5 patients are alive including 4 with their original grafts. One patient was retransplanted at 9 months. Major complications were infections, which were responsible for 3 deaths due to multiorgan septic failure (2 during the first month); rejection episodes (4 biopsy-proven of humoral rejections in 3 patients and 1 cellular rejection) and biliary. CONCLUSION: The use of ABOi LT as a life-saving procedure is justifiable in emergencies when no other donor is available. With careful recipient selection close monitoring of hemagglutinins and specific immunosuppression we have obtained acceptable outcomes.

Variantes Genéticas Pró-Trombóticas como (Improváveis?) Factores de Risco para as Grandes Crises Vaso-Oclusivas na Drepanocitose

CONTEXTO: A drepanocitose é uma anemia hemolítica hereditária com características pró-adesivas, pró-inflamatórias e pró-coagulantes, incluindo alterações na hemostase e activação da cascata da coagulação. PLANO DO ESTUDO: Neste estudo analisaram-se, em 140 drepanocíticos africanos e 126 indivíduos sem hemoglobina S também de origem africana, variantes genéticas polimórficas em quatro loci envolvidos na coagulação (F2 20210G>A e F5 R506Q), na fibrinólise (PAI-1 5G>4G), ou no metabolismo da homocisteína (MTHFR 677C>T). Estratificaram-se os pacientes em dois grupos de acordo com a ocorrência ou não de, pelo menos, uma complicação vaso-oclusiva (CVO) grave até à data da sua participação no estudo. RESULTADOS: Não se observou uma associação estatisticamente significativa entre a ocorrência de uma CVO grave e a herança do alelo predisponente à trombose, 4G no locus PAI-1 ou 677T no locus MTHFR. Nenhum drepanocítico apresentava os alelos F2 20210A ou F5 506Q (factor V Leiden). Visando excluir a possibilidade de que genuínas diferenças inter-grupos fossem mascaradas pela presença de indivíduos mais jovens no grupo sem-CVO, dividiu-se este num sub-grupo de pacientes mais novos e num sub-grupo de pacientes cuja idade não diferia significativamente do grupo com-CVO grave. Mesmo assim, não foi encontrada associação significativa. No entanto, pode observar-se, no grupo de doentes com o alelo PAI-1 4G (cuja expressão resulta numa diminuição da actividade fibrinolítica), uma tendência (OR=1,6) para um risco acrescido de CVO. Esta tendência era ligeiramente maior (OR=2,1) se se considerasse apenas a CVO síndrome torácica aguda. CONCLUSÕES: O alelo 4G no promotor do PAI-1 poderá ser um factor de risco para CVO na drepanocitose, uma hipótese a testar numa série maior de doentes, idealmente oriunda de uma população homogénea e com alta prevalência de drepanocitose.

Transplant Glomerulopathy: Clinico-Pathologic Features

Transplant glomerulopathy is a sign of chronic kidney allograft damage. It has a distinct morphology and is associated with poor allograft survival. We aimed to assess the prevalence and clinic-pathologic features of transplant glomerulopathy, as well as determine the functional and histological implications of its severity. We performed a single-centre retrospective observational study during an eight-year period. Kidney allograft biopsies were diagnosed and scored according to the Banff classification, coupled with immunofluorescence studies. The epidemiology, clinical presentation, outcomes (patient and graft survival) and anti-HLA alloantibodies were evaluated. Transplant glomerulopathy was diagnosed in 60 kidney transplant biopsies performed for clinical reasons in 49 patients with ABO compatible renal transplant and a negative T-cell complement dependent cytotoxicity crossmatch at transplantation. The estimated prevalence of transplant glomerulopathy was 7.4% and its cumulative prevalence increased over time. C4d staining in peritubular capillaries (27.6%) was lower than the frequency of anti-HLA antibodies (72.5%), the majority against both classes I and II. Transplant glomerulopathy was associated with both acute (mainly glomerulitis and peritubular capillaritis) and chronic histologic abnormalities. At diagnosis, 30% had mild, 23.3% moderate and 46.7% severe transplant glomerulopathy. The severity of transplant glomerulopathy was associated with the severity of interstitial fibrosis. Other histological features, as well as clinical manifestations and graft survival, were unrelated to transplant glomerulopathy severity.