Christine A. O'Mahony

Quantitative EBV viral loads and immunosuppression alterations can decrease PTLD incidence in pediatric liver transplant recipients

Epstein–Barr virus (EBV) is a common viral infection in pediatric liver transplant patients and can lead to development of post‐transplant lymphoproliferative disorder (PTLD). Differing studies have used immunosuppression reduction, antiviral medications or i.v. CMV‐immunogloublin for EBV prevention and treatment. The purpose of this study was to determine whether implementation of a protocol for frequent EBV monitoring and EBV viral load‐driven immunosuppression reduction could decrease the incidence of PTLD in our patient population. All data were prospectively collected between 2001 and 2004 at a single institution. Seventy‐three patients were entered into the study. Patients were divided into a historical control group (pre‐2001, 30 patients) and a treatment group (post‐2001, 43 patients). Approximately 1271 blood samples of 73 patients were collected between 2001 and 2004. Eleven out of 43 patients received immunosuppression tapering due to high EBV viral loads (>4000 copies/μg DNA). One patient developed allograft rejection after immunosuppression modulation. Prior to 2001, the incidence of PTLD at our institution was 16%. After instituting a protocol for EBV monitoring, the incidence of PTLD decreased to 2% (p‐value < 0.05). These findings illustrate that frequent EBV viral load monitoring and preemptive immunosuppression modulation have an integral role in preventing PTLD in the pediatric liver transplant population.

Successful liver transplantation following medical management of portopulmonary hypertension: a single-center series.

Severe portopulmonary hypertension (POPH) is an absolute contraindication to orthotopic liver transplantation (OLT). Vasodilators have been used, but the safety of subsequent transplantation and the reversibility of pulmonary hypertension after transplantation are uncertain. This study examined the feasibility and post‐transplant effects of liver transplantation following medical control of POPH. Eight consecutive patients (three females and five males, ages 39–51) with POPH as their only contraindication to transplantation were treated with continuous intravenous epoprostenol. Liver transplantation was considered if the mean pulmonary artery pressure (PAM) was lowered to <35 mmHg. Epoprostenol 2–8 ng/kg/min successfully improved hemodynamics in seven of eight patients, usually within 6.5 months of initiating therapy. PAM declined from an average of 43–33 mmHg (p = 0.03); mean pulmonary vascular resistance declined from 410 to 192 dyn s cm−5 (p = 0.01) and cardiac output increased from 6.6 to 10 L/min (p = 0.02). Six of the seven responders were actively listed for liver transplantation. Two died on the waiting list; the remaining four were transplanted and remain alive and well 9–18 months post‐OLT—two without vasodilators, and two on oral medication. We conclude that pulmonary vasodilators permit safe liver transplantation in some cases, and that POPH may be reversible after transplantation.

Liver Tumors: Pediatric Population

Liver tumors in childhood are rare and are typically not detected clinically until they reach a large size and often spread within the organ or metastasize. This can make surgical resection problematic, and almost all of them require extirpation for cure. With very effective chemotherapy for hepatoblastoma and to some extent for sarcomas, many cancers can be shrunk to permit partial hepatectomy, but for most hepatocarcinomas, some of the other malignancies, and even some benign proliferations, their location at the hilum and multiplicity of masses in multiple lobes make transplantation the treatment of choice. Major advances in diagnostic imaging, especially enhanced computed tomography and magnetic resonance imaging, permit a preoperative choice of resection versus transplantation to be achieved in almost all instances, and for the remainder, intraoperative ultrasonography can further help to determine the most desirable approach. The outcome is very much better in the case of hepatoblastoma when transplantation is a primary modality rather than following unsuccessful attempts at resection. In this review, transplantation for liver tumors in children is considered from all aspects, including the importance of screening for tumors whenever possible to avoid the need for transplantation. Liver Transpl 14:1545–1556, 2008.

Intracellular glutathione in the peripheral blood cells of HIV-infected patients: failure to show a deficiency.

Objective:To determine whether HIV-infected patients have a deficiency of intracellular glutathione (GSH) in peripheral blood mononuclear cells (PBMC) and erythrocytes. Design:Initial experiments determining the stability of intracellular GSH preceded the measurement of GSH levels in 33 HIV-positive patients and 40 control subjects within 1 h of isolation of their blood cells. In addition, the susceptibility of erythrocytes to dapsone hydroxylamine-induced methaemoglobinaemia was evaluated. Methods:GSH levels were determined by an high-performance liquid chromatography method utilizing a fluorescent probe, monobromobimane. The bimane–GSH adduct formed in PBMC was also characterized by mass spectrometry. Methaemoglobin formation on exposure to dapsone hydroxylamine was determined spectrophotometrically. Results:GSH levels remained stable for only 1 h after cell isolation, thereafter showing a decrease of 20 and 60% at 4 and 24 h, respectively. There was no difference in the GSH levels in PBMC and erythrocytes of the HIV-positive patients compared with controls. The GSH levels were not related to the disease stage or to CD4+ cell counts. There was no difference in GSH levels in PBMC taken from trimethoprim–sulphamethoxazole-hypersensitive and non-hypersensitive patients. Methaemoglobinaemia on exposure of erythrocytes to dapsone hydroxylamine was concentration-dependent, but there was no significant difference between patients and controls. Conclusion:In contrast to previous studies, no deficiency of intracellular GSH in the PBMC and erythrocytes of HIV-infected patients was found. The discrepancy between studies may be methodological reflecting the instability of GSH, which requires prompt sample analysis.

Evaluation and management of patients with propionic acidemia undergoing liver transplantation: a comprehensive review.

Abstract:  Propionic acidemia is a rare metabolic disorder that often results in episodic hyperammonemia, basal ganglia infarction, mental retardation, and cardiomyopathy. OLT has been used as a treatment for propionic acidemia, but its benefit in patients with this disease is unclear. The current study was undertaken to clarify the role of OLT in the management of this disease. The medical literature, a national registry of US OLT recipients, and a single institution liver transplant experience were reviewed for cases of OLT for propionic acidemia. Accumulated cases demonstrate that OLT has resulted in clear evidence of clinical improvement in several patients, often obviating the need for dietary restriction or other forms of medical management. OLT appears to halt the decline in neurocognitive function often associated with propionic acidemia. In total, 12 patients with propionic acidemia have undergone a total of 14 OLTs. A quantitative analysis of outcomes shows an overall patient survival rate of 72.2% at one year after OLT. In conclusion, OLT should be considered a treatment option for patients with propionic acidemia who continue to experience episodes of hyperammonemia in spite of maximal medical therapy. Early OLT may limit the development of mental retardation and/or cardiomyopathy.

New patient-applied therapy for anogenital warts is rated favourably by patients

Our objective was to determine patient attitudes to having genital warts, and their perceptions of their treatment with imiquimod and other therapies. As an adjunct to a clinical trial in which patients with external genital warts were treated with imiquimod 5% cream until their warts cleared or for up to 16 weeks, quantitative questionnaires consisting of multiple choice questions and 5-point rating scales were completed prior to, and at the end, of the study period. Pre-study and post-study questionnaires were completed by 902 and 629 patients, respectively. Patients expressed a definite concern about genital warts. The majority of patients (70%) had been previously treated for genital warts, and expressed dissatisfaction with their previous therapies. Of patients treated with imiquimod in this study, 82% reported that their warts decreased in size; this occurred within the first 4 weeks for 78% of patients. Sixty-one per cent of patients perceived that their warts completely cleared within the 16-week treatment period. Patients rated imiquimod 5% cream as better than other genital wart therapies in terms of overall satisfaction, time to clearance, convenience and lack of associated pain. In conclusion, patients rated imiquimod 5% cream as an effective treatment which clears warts in an acceptable length of time causing minimal pain and is convenient to use.

The natural history of hepatitis C virus in pediatric liver transplant recipients

Although rare in the pediatric population, the natural history of hepatitis C virus (HCV) recurrence in pediatric patients undergoing orthotopic liver transplantation (OLT) for end‐stage liver disease secondary to HCV has not been well described. We performed an analysis of all 67 pediatric patients (<17 years old) who have undergone OLT for HCV in the United States between 1/1988 and 6/2005. The 67 pediatric patients received a total of 83 OLTs for HCV. Following initial OLTs performed for HCV, the patient and allograft survival rates were 71.6% and 55.0%, respectively, at 5 years. Following retransplantation these rates decreased to 55.0% and 33.8%, respectively, following retransplantation. Recipients were listed for retransplantation after 31.3% of all OLTs, and overall recipients were retransplanted after 19.3% of OLTs. The overwhelming majority of retransplants were performed for HCV recurrence. A mean of 1.2 OLTs were performed per patient for HCV. The median time between OLTs for HCV was 290 days. In conclusion, the risk of HCV recurrence in pediatric OLT recipients is high and is associated with a high rate of retransplantation. Still, OLT represents the only treatment option that may achieve long‐term survival in pediatric patients with end‐stage liver disease secondary to HCV that is recalcitrant to medical management. Liver Transpl 12:1119–1123, 2006.

Treatment of Liver Metastases in Patients with Neuroendocrine Tumors: A Comprehensive Review

Patients diagnosed with Neuroendocrine Tumors (NET) often are also diagnosed with Neuroendocrine Liver Metastases (NLM) during the course of their disease. NLM can cause significant morbidity and mortality, oftentimes much more than compared to patients with NET. Treatment options have been limited in the past, focusing on surgical resections, for which only a minority of patients are candidates. However, developments of new treatment modalities have progressed rapidly and patients with NLM now have significantly more options, including surgical-directed therapies; liver-directed therapies; and nonsurgical, non-liver-directed therapies. This review provides information about the roles of hepatic resection, orthotopic liver resection, radiofrequency ablation, hepatic artery embolization and hepatic artery chemoembolization, hepatic artery radioembolization and selective internal radiation therapy, peptide receptor radionuclide therapy, systemic chemotherapy, biotherapies including somatostatin analogs and interferon-α, vascular endothelial growth factor and mTOR targets, and microRNA-regulated pathways. Given these new options, the clinician can tailor therapy specific to the patient diagnosed with NLM, thereby giving the patient the best possible chance of prolonged survival.

Neuroendocrine Liver Metastases and Orthotopic Liver Transplantation: The US Experience

Liver transplantation remains a controversial therapy for Neuroendocrine liver metastases (NLM), with coflicting suvival data reported. The aim was to assess the evolution of outcomes for patients transplanted for NLM in the US, both before and after the introduction of the MELD scoring system in 2002. The UNOS/OPTN database was reviewed to identify patients diagnosed with NLM who subsequently underwent a liver transplantation from 1988 to March 2011 (n = 184); Patient survival was determined using Kaplan-Meier methods and log-rank tests, and cox regression analysis was performed, using SPSS 15.0 (SPSS, Inc, Chicago, IL). The overall NLM patient survivals in the pre-MELD era were 79.5%, 61.4%, and 49.2% at 1, 3, and 5 years, respectively. After the introduction of the MELD score, NET/NLM patients had improved overall patient survivals at 1, 3, and 5 years of 84.7%, 65%, and 57.8%. Patients transplanted after 2002 had an improved survival outcome. Notably, the overall patient survival for NET is not significantly different when compared to the outcomes of patients transplanted for HCC, in the current era. This progress acknowleges the significant improvement in outcomes for NLM patients after liver transplantation and the potential for further gain in the survival of otherwise nonsurgical, terminal patients.

An Early Regional Experience with Expansion of Milan Criteria for Liver Transplant Recipients

The Milan Criteria (MC) showed that orthotopic liver transplantation (OLT) was an effective treatment for patients with nonresectable, nonmetastatic HCC. There is growing evidence that expanding the MC does not adversely affect patient or allograft survival following OLT.