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Trapianto di fegato con l’utilizzo di grafts da donatori HBsAg positivi: studio multicentrico italiano
No full textIntroduzione e Scopi:
Il trapianto di fegato è diventato il trattamento di scelta per la cura ed il trattamento delle malattie epatiche terminali non più suscettibili di terapia medica, con un tasso di sopravvivenza del paziente di oltre l’80% ad un anno. Tuttavia la crescente domanda di organi da trapiantare ha superato la disponibilità con conseguenti lunghi periodi di attesa in lista ed inevitabilmente un alto tasso di mortalità in lista di attesa. La comunità trapiantologica ha cercato di rispondere a questa continua esigenza sviluppando diverse strategie come, ad esempio, l’utilizzo di grafts da donatori definiti marginali. Questi comprendono i donatori “a cuore non-battente”, i donatori anziani (oltre i 65 anni), l’utilizzo di grafts con moderata steatosi o con pregresse infezioni da epatite-B o epatite-C. Un ulteriore possibilità per incrementare il pool dei donatori è l’utilizzo di grafts da donatori HBsAg-positivi. Tuttavia, ad oggi, pochi dati sono disponibili sull’utilizzo di questi grafts. Il nostro obiettivo è stato valutare lo stato siero-virologico ed i risultati clinici del trapianto di fegato utilizzando grafts da donatori HBsAg-positivi.
Materiali e Metodi:
Questo è uno studio multicentrico che ha coinvolto l’Università di Modena, Bologna e Padova. Lo studio è stato approvato dai comitati etici di ogni centro trapianto. Sono stati retrospettivamente valutati i pazienti trapiantati di fegato dal 12 marzo 2004 al 21 maggio 2010. In questo periodo 28 pazienti hanno ricevuto un fegato da donatori HBsAg-positivi. La valutazione sierovirologica ha incluso: i markers per HBV, IgM e IgG anti HDV, anticorpi anti-HCV, sierologia per Herpes virus e IgG Toxoplasma. In aggiunta è stato eseguito il dosaggio per HBV-DNA. Per ottenere l’idoneità del graft erano obbligatori due parametri: l’istologia del fegato che doveva documentare uno score di fibrosi (sec. Ishak) <1 e/o una lieve attività infiammatoria (grado <4). Il decorso clinico di ogni paziente è stato retrospettivamente valutato e sono stati raccolti i dati riguardanti: il tipo di terapia immunosoppressiva, gli episodi di rigetto cellulare acuto, la recidiva istologica di epatite-B ed il trattamento antivirale durante le recidive di epatite-B. Infine è stato analizzata la sopravvivenza del graft e del paziente intese come tempo intercorso dal trapianto al decesso del paziente e/o al ritrapianto.
Risultati:
L’età media dei riceventi era di 57.6 anni (range: 26-67); 4 dei 28 pazienti trapiantati erano femmine (14.3%). Il follow-up medio è stato di 37.4 mesi (0.1-88). Il tempo medio di attesa in lista è stato di 452 giorni (range: 37-1962) ed il MELD score medio al momento del trapianto era 15.6 (7-33). 19 pazienti avevano un carcinoma epatocellulare (7.8%) che in 13 casi (68.4%) rientrava entro i criteri di Milano. L’età media dei donatori HBsAg-positivi era di 52.6 anni (range:13-79) ed il tempo medio in rianimazione è stato di 5.3 giorni (range: 1-21). Il tempo medio di ischemia fredda e di ischemia calda del graft è stata di 430 e 40 minuti, rispettivamente. La degenza media postoperatoria è stata di 21.4 giorni (range: 6-143). Durante il follow-up nessun paziente ha necessitato di un ritrapianto di fegato, due pazienti (7.1%) svilupparono un rigetto cellulare acuto, 7 pazienti (25%) presentarono una complicanza biliare e 5 (17.9%) una infezione maggiore. La sopravvivenza del graft e del paziente a 1-,3- e 5 anni è stata del 85.6%, 81.7% e 74.3% rispettivamente.
Conclusioni:
Sulla base dei nostri risultati possiamo concludere che il trapianto di fegato con l'utilizzo di grafts da donatori HBsAg-positivi può essere sicuro e la recidiva di epatite B può essere controllata soprattutto con una adeguata selezione del graft e attraverso una appropriata gestione postoperatoria della terapia antivirale.Background & Aims: Liver transplantation (LT) has become the definitive procedure for management of end stage liver disease, with survival rates greater than 80% at 1 year. The increase in organ demand has exceeded the supply, resulting in longer waiting periods and higher death rates on the waiting list. Approximately 10% to 20% of patients on the liver transplant list die each year without receiving an organ in a timely fashion. Transplant physicians have responded to this increased demand by developing several strategies such as the use of “expanded criteria donors” grafts. These could include non-heart-beating donors, older donors (aged 65 years and over), and the use of liver allografts containing appreciable steatosis or with past exposure to hepatitis B or hepatitis C. A further possibility to increase the organ pool is to use grafts from hepatitis B virus surface antigen (HBsAg) positive donors but few data are currently available in this setting. We assessed the clinical and sero-virological status and outcomes of liver transplantation from HBsAg positive donors in a multicenter study.
Methods: This was a multicenter study involving 3 Liver Transplant Centers in Italy: the Universities of Modena, Bologna and Padova. The study was approved by the institutional review boards at each center. Patients undergoing liver transplantation between March 12, 2004, and May 21, 2010, were retrospectively evaluated. 28 patients received liver grafts from HBsAg positive deceased donors. All subjects were informed of the possible risks, consented to enter the study and signed a written form. The serovirological assessment includes a complete HBV marker panel, anti HDV IgG and IgM. Anti-HCV Ab, plus Herpes virus serology and Toxoplasma IgG. An HBV-DNA test is also performed. To establish graft suitability, two parameters are strictly mandatory: liver pathology, that must document a fibrosis Ishak score <1 and only mild inflammation (grading score <4). The clinical course of each patient was retrospectively evaluated: data on immunosuppression, episodes of acute rejection, histological hepatitis B recurrence, and antiviral treatment of hepatitis B recurrence were collected. Finally, we recorded information on graft and patient survival, calculating time to retransplantation or death.
Results:
The average age of recipients at LT was 57.6 years (range: 26-67), 4 out of 28 were female (14.3%). The average follow up after LT was 37.4 months (range: 0.1-88). The patients were transplanted after an average waiting time of 452 days (range: 37-1962) and at the time of LT presented an average MELD score of 15.6 (range: 7-33). 19 patients had hepatocellular carcinoma (67.8%) that in 13 cases (68.4%) resulted within the Milan criteria. The HBsAg positive donors had an average age of 52.6 years (range:13-79) and an average stay in ICU of 5.3 days (range: 1-21). The average cold ischemia time and warm ischemia time resulted of 430 and 40 minutes respectively. After LT the average hospital stay was of 21.4 days (range: 6-143). During the follow up none of the patients required retransplantation, 2 patients (7.1%) developed an acute cellular rejection, 7 (25%) presented biliary complications and 5 (17.9%) major infections. The 1-, 3- and 5-year graft and patient survival resulted of 85.6%, 81.7% and 74.3% respectively.
Conclusions
In conclusion, the utilization of grafts from deceased HBsAg-positive donors may be feasible and HBV can be controlled with graft stability if selection of grafts and postoperative antiviral treatment are appropriately managed. Long-term follow-up data and large-scale multi-center studies are required to confirm our findings
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