Tailoring allocation policies and improving access to paediatric liver transplantation over a 16-year period.

BACKGROUND & AIMS: Mortality on the paediatric liver transplantation (pLT) waiting list (WL) is still an issue. We analysed the Italian pLT WL to evaluate the intention-to-treat (ITT) success rate and to identify factors influencing success. METHODS: All children (<18 years) listed for pLT in Italy between 2002-2018 were included (Era 1 [2002-2007]: centre-based allocation; Era 2 [2008-2014]: national allocation; Era 3 [2015-2018]: national allocation+mandatory-split policy). RESULTS: A total of 1,424 patients (median age: 2.0 [IQR 1.0-9.0] years; median weight: 12.0 kg [IQR 7-27]) were listed for pLT. Median WL time was 2 days (IQR 1-5) for Status 1 and 44 days (IQR 15-120) for non-Status 1 patients; 1,302 children (91.4%) were transplanted (67.3% with split grafts), while 50 children (3.5%) dropped off the WL (2.5% death, 1.0% clinical deterioration). Predictive factors for receiving LT included Status 1 (hazard ratio [HR] 1.66, p = 0.001), Status 1B (HR 1.96, p = 0.016), Status 2A (HR 2.15, p = 0.024) and each 1-point increase in PELD/MELD score. Children with recipient's weight >25 kg, blood group O or awaiting pLT combined with other organs had less chance of being transplanted. ITT patient survival rates were 90.5% at 1 year and 87.5% at 5 years, remaining stable across eras. Risk factors for ITT survival were re-transplantation (HR 5.83, p <0.001), Status 1 (HR 2.28, p = 0.006), Status 1B (HR 2.90, p = 0.014), Status 2A (HR 9.12, p <0.001), recipient weight <6 kg (HR 4.53, p <0.001) and low-volume activity (HR 4.38, p = 0.001). CONCLUSIONS: In Italy, continuous adaption of paediatric organ allocation policies via the introduction of national allocation, paediatric prioritisation rules and a mandatory-split policy have helped maximise the use of donors for paediatric candidates and to minimise WL mortality without compromising outcomes. IMPACT AND IMPLICATIONS: Globally, paediatric liver transplant candidates still suffer from high mortality. Over recent decades, the continuous adaption of organ allocation policies in Italy has led to excellent outcomes for children awaiting liver transplantation. The mortality rate of paediatric liver transplant candidates has been minimised to almost zero, mainly using grafts from deceased donors. Paediatric prioritisation rules, national organ exchange organisation and a mandatory-split liver policy have resulted in a unique allocation model for paediatric liver transplant candidates and represent a landmark for the paediatric transplant community.

Effect of Migalastat on cArdiac InvOlvement in FabRry DiseAse: MAIORA study.

BACKGROUND: A small but significant reduction in left ventricular (LV) mass after 18 months of migalastat treatment has been reported in Fabry disease (FD). This study aimed to assess the effect of migalastat on FD cardiac involvement, combining LV morphology and tissue characterisation by cardiac magnetic resonance (CMR) with cardiopulmonary exercise testing (CPET). METHODS: Sixteen treatment-naïve patients with FD (4 women, 46.4±16.2 years) with cardiac involvement (reduced T1 values on CMR and/or LV hypertrophy) underwent ECG, echocardiogram, troponin T and NT-proBNP (N-Terminal prohormone of Brain Natriuretic Peptide) assay, CMR with T1 mapping, and CPET before and after 18 months of migalastat. RESULTS: No change in LV mass was detected at 18 months compared to baseline (95.2 g/m2 (66.0-184.0) vs 99.0 g/m2 (69.0-121.0), p=0.55). Overall, there was an increase in septal T1 of borderline significance (870.0 ms (848-882) vs 860.0 ms (833.0-875.0), p=0.056). Functional capacity showed an increase in oxygen consumption (VO2) at anaerobic threshold (15.50 mL/kg/min (13.70-21.50) vs 14.50 mL/kg/min (11.70-18.95), p=0.02), and a trend towards an increase in percent predicted peak VO2 (72.0 (63.0-80.0) vs 69.0 (53.0-77.0), p=0.056) was observed. The subset of patients who showed an increase in T1 value and a reduction in LV mass (n=7, 1 female, age 40.5 (28.6-76.0)) was younger and at an earlier disease stage compared to the others, and also exhibited greater improvement in exercise tolerance. CONCLUSION: In treatment-naïve FD patients with cardiac involvement, 18-month treatment with migalastat stabilised LV mass and was associated with a trend towards an improvement in exercise tolerance. A tendency to T1 increase was detected by CMR. The subset of patients who had significant benefits from the treatment showed an earlier cardiac disease compared to the others. TRIAL REGISTRATION NUMBER: NCT03838237.

European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (1) pre-transplant evaluation.

BACKGROUND: Liver transplantation is the state-of-the-art curative treatment in end-stage liver disease. Imaging is a key element for successful organ-transplantation to assist surgical planning. So far, only limited data regarding the best radiological approach to prepare children for liver transplantation is available. OBJECTIVES: In an attempt to harmonize imaging surrounding pediatric liver transplantation, the European Society of Pediatric Radiology (ESPR) Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phase. This paper reports the responses on preoperative imaging. MATERIAL AND METHODS: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted and 22 institutions from 11 countries returned the survey. From 2018 to 2020, the participating centers collectively conducted 1,524 transplantations, with a median of 20 transplantations per center per annum (range, 8-60). RESULTS: Most sites (64%) consider ultrasound their preferred modality to define anatomy and to plan surgery in children before liver transplantation, and additional cross-sectional imaging is only used to answer specific questions (computed tomography [CT], 90.9%; magnetic resonance imaging [MRI], 54.5%). One-third of centers (31.8%) rely primarily on CT for pre-transplant evaluation. Imaging protocols differed substantially regarding applied CT scan ranges, number of contrast phases (range 1-4 phases), and applied MRI techniques. CONCLUSION: Diagnostic imaging is generally used in the work-up of children before liver transplantation. Substantial differences were noted regarding choice of modalities and protocols. We have identified starting points for future optimization and harmonization of the imaging approach to multicenter studies.

European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (3) postoperative imaging.

BACKGROUND: Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of postoperative complications. So far, limited data is available regarding the best radiologic approach to monitor children after liver transplantation. OBJECTIVE: To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra-, and postoperative phases. This paper reports the responses related to postoperative imaging. MATERIALS AND METHODS: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey. RESULTS: All sites commence ultrasound (US) monitoring within 24 h after liver transplantation. Monitoring frequency varies across sites, ranging from every 8 h to 72 h in early, and from daily to sporadic use in late postoperative phases. Predefined US protocols are used by 73% of sites. This commonly includes gray scale, color Doppler, and quantitative flow assessment. Alternative flow imaging techniques, contrast-enhanced US, and elastography are applied at 31.8%, 18.2%, and 63.6% of sites, respectively. Computed tomography is performed at 86.4% of sites when clarification is needed. Magnetic resonance imaging is used for selected cases at 36.4% of sites, mainly for assessment of biliary abnormalities or when blood tests are abnormal. CONCLUSION: Diagnostic imaging is extensively used for postoperative surveillance of children after liver transplantation. While US is generally prioritized, substantial differences were noted in US protocol, timing, and monitoring frequency. The study highlights potential areas for future optimization and standardization of imaging, essential for conducting multicenter studies.

European Society of Pediatric Radiology survey of perioperative imaging in pediatric liver transplantation: (2) intraoperative imaging.

BACKGROUND: Liver transplantation is the state-of-the-art curative treatment for end-stage liver disease. Imaging is a key element in the detection of intraoperative and postoperative complications. So far, only limited data regarding the best radiological approach to monitor children during liver transplantation is available. OBJECTIVE: To harmonize the imaging of pediatric liver transplantation, the European Society of Pediatric Radiology Abdominal Taskforce initiated a survey addressing the current status of imaging including the pre-, intra- and postoperative phase. This paper reports the responses related to intraoperative imaging. MATERIALS AND METHODS: An online survey, initiated in 2021, asked European centers performing pediatric liver transplantation 48 questions about their imaging approach. In total, 26 centers were contacted, and 22 institutions from 11 countries returned the survey. RESULTS: Intraoperative ultrasound (US) is used by all sites to assess the quality of the vascular anastomosis in order to ensure optimal perfusion of the liver transplant. Vessel depiction is commonly achieved using color Doppler (95.3%). Additional US-based techniques are employed by fewer centers (power angio mode, 28.6%; B-flow, 19%; contrast-enhanced US, 14.3%). Most centers prefer a collaborative approach, with surgeons responsible for probe handling, while radiologists operate the US machine (47.6%). Less commonly, the intraoperative US is performed by the surgeon alone (28.6%) or by the radiologist alone (23.8%). Timing of US, imaging frequency, and documentation practices vary among centers. CONCLUSION: Intraoperative US is consistently utilized across all sites during pediatric liver transplantation. However, considerable variations were observed in terms of the US setup, technique preferences, timing of controls, and documentation practices. These differences provide valuable insights for future optimization and harmonization studies.

Achievement of operational tolerance in a pediatric liver transplant recipient following successful hematopoietic stem cell transplantation from a different donor.

Hematopoietic stem cell transplantation (HSCT)-based approaches are increasingly investigated strategies to induce tolerance in recipients of solid allografts. However, in the majority of cases, these approaches rely on the infusion of hematopoietic stem cells recovered from the same solid organ donor. In this report, we describe the case of a boy who received liver transplantation from a deceased donor, who had successfully underwent allogeneic HSCT from an unrelated donor for hepatitis-associated aplastic anemia. In this patient, it was possible to permanently withdraw post-HSCT immune suppression without causing any sign of liver graft dysfunction. To the best of our knowledge, this is the first case of operational tolerance documented in a patient who received combined liver transplantation and HSCT from different donors.

Improving outcomes of in situ split liver transplantation in Italy over the last 25 years.

BACKGROUND & AIMS: Split liver transplant(ation) (SLT) is still considered a challenging procedure that is by no means widely accepted. We aimed to present data on 25-year trends in SLT in Italy, and to investigate if, and to what extent, outcomes have improved nationwide during this time. METHODS: The study included all consecutive SLTs performed from May 1993 to December 2019, divided into three consecutive periods: 1993-2005, 2006-2014, and 2015-2019, which match changes in national allocation policies. Primary outcomes were patient and graft survival, and the relative impact of each study period. RESULTS: SLT accounted for 8.9% of all liver transplants performed in Italy. A total of 1,715 in situ split liver grafts were included in the analysis: 868 left lateral segments (LLSs) and 847 extended right grafts (ERGs). A significant improvement in patient and graft survival (p <0.001) was observed with ERGs over the three periods. Predictors of graft survival were cold ischaemia time (CIT) <6 h (p = 0.009), UNOS status 2b (p <0.001), UNOS status 3 (p = 0.009), and transplant centre volumes: 25-50 cases vs. <25 cases (p = 0.003). Patient survival was significantly higher with LLS grafts in period 2 vs. period 1 (p = 0.008). No significant improvement in graft survival was seen over the three periods, where predictors of graft survival were CIT <6 h (p = 0.007), CIT <6 h vs. ≥10 h (p = 0.019), UNOS status 2b (p = 0.038), and UNOS status 3 (p = 0.009). Retransplantation was a risk factor in split liver graft recipients, with significantly worse graft and patient survival for both types of graft (p <0.001). CONCLUSIONS: Our analysis showed Italian SLT outcomes to have improved over the last 25 years. These results could help to dispel reservations regarding the use of this procedure. IMPACT AND IMPLICATIONS: Split liver transplant(ation) (SLT) is still considered a challenging procedure and is by no means widely accepted. This study included all consecutive in situ SLTs performed in Italy from May 1993 to December 2019. With more than 1,700 cases, it is one of the largest series, examining long-term national trends in in situ SLT since its introduction. The data presented indicate that the outcomes of SLT improved during this 25-year period. Improvements are probably due to better recipient selection, refinements in surgical technique, conservative graft-to-recipient matching, and the continuous, yet carefully managed, expansion of donor selection criteria under a strict mandatory split liver allocation policy. These results could help to dispel reservations regarding the use of this procedure.

Missense variants in RPH3A cause defects in excitatory synaptic function and are associated with a clinically variable neurodevelopmental disorder.

PURPOSE: RPH3A encodes a protein involved in the stabilization of GluN2A subunit of N-methyl-D-aspartate (NMDA)-type glutamate receptors at the cell surface, forming a complex essential for synaptic plasticity and cognition. We investigated the effect of variants in RPH3A in patients with neurodevelopmental disorders. METHODS: By using trio-based exome sequencing, GeneMatcher, and screening of 100,000 Genomes Project data, we identified 6 heterozygous variants in RPH3A. In silico and in vitro models, including rat hippocampal neuronal cultures, have been used to characterize the effect of the variants. RESULTS: Four cases had a neurodevelopmental disorder with untreatable epileptic seizures [p.(Gln73His)dn; p.(Arg209Lys); p.(Thr450Ser)dn; p.(Gln508His)], and 2 cases [p.(Arg235Ser); p.(Asn618Ser)dn] showed high-functioning autism spectrum disorder. Using neuronal cultures, we demonstrated that p.(Thr450Ser) and p.(Asn618Ser) reduce the synaptic localization of GluN2A; p.(Thr450Ser) also increased the surface levels of GluN2A. Electrophysiological recordings showed increased GluN2A-dependent NMDA ionotropic glutamate receptor currents for both variants and alteration of postsynaptic calcium levels. Finally, expression of the Rph3AThr450Ser variant in neurons affected dendritic spine morphology. CONCLUSION: Overall, we provide evidence that missense gain-of-function variants in RPH3A increase GluN2A-containing NMDA ionotropic glutamate receptors at extrasynaptic sites, altering synaptic function and leading to a clinically variable neurodevelopmental presentation ranging from untreatable epilepsy to autism spectrum disorder.

An expert consensus on the recommendations for the use of biomarkers in Fabry disease.

Fabry disease is an X-linked lysosomal storage disorder caused by the accumulation of glycosphingolipids in various tissues and body fluids, leading to progressive organ damage and life-threatening complications. Phenotypic classification is based on disease progression and severity and can be used to predict outcomes. Patients with a classic Fabry phenotype have little to no residual α-Gal A activity and have widespread organ involvement, whereas patients with a later-onset phenotype have residual α-Gal A activity and disease progression can be limited to a single organ, often the heart. Diagnosis and monitoring of patients with Fabry disease should therefore be individualized, and biomarkers are available to support with this. Disease-specific biomarkers are useful in the diagnosis of Fabry disease; non-disease-specific biomarkers may be useful to assess organ damage. For most biomarkers it can be challenging to prove they translate to differences in the risk of clinical events associated with Fabry disease. Therefore, careful monitoring of treatment outcomes and collection of prospective data in patients are needed. As we deepen our understanding of Fabry disease, it is important to regularly re-evaluate and appraise published evidence relating to biomarkers. In this article, we present the results of a literature review of evidence published between February 2017 and July 2020 on the impact of disease-specific treatment on biomarkers and provide an expert consensus on clinical recommendations for the use of those biomarkers.

Safety, efficacy, and timing of transplantation(s) in propionic and methylmalonic aciduria.

Propionic (PA) and methylmalonic aciduria (MMA) share many clinical similarities, which include the risk of acute metabolic encephalopathies, and some long-term complications, such as optic neuropathy, pancreatic involvement, developmental disability, and similar management approaches, but they also represent distinct clinical and biochemical entities. In the severe forms of PA and MMA, most long-term complications cannot be prevented with conventional clinical management. Organ transplantation represents a form of partial enzyme replacement to improve the long-term outlook for these disorders. There is evidence that early liver transplant in both disorders greatly improves metabolic stability and reduces the risk of long-term complications. For MMA, early liver transplant reduces methylmalonic acid levels which in turns reduces its effects on kidneys, and therefore slows progression of chronic kidney disease. However, established organ damage cannot be reversed. For patients with MMA who present with chronic kidney disease, consideration should be given for combined liver and kidney transplants. Transplantation in PA and MMA carries a high risk of complications and requires highly specialised pre-operative and peri-operative management. Involvement of a multidisciplinary team is essential and should include metabolic team, nephrologist, hepatologist, hepatobiliary and renal transplant surgeons, anaesthesiologists, cardiologists, intensive care team, dieticians and specialist nurses. These patients require life-long multidisciplinary follow-up. There is increasing evidence in the literature on excellent short to medium-term patient and allograft survival following transplantation when patients are managed by a multidisciplinary team in a specialist centre. Improved early diagnosis and reductions in transplant-related mortality and morbidity have allowed early transplantation to be used electively to further improve the outcome.

The impact of liver transplantation on health-related quality of life in (acute) intoxication-type inborn errors of metabolism.

Organic acidurias (OAs), urea-cycle disorders (UCDs), and maple syrup urine disease (MSUD) belong to the category of intoxication-type inborn errors of metabolism (IT-IEM). Liver transplantation (LTx) is increasingly utilized in IT-IEM. However, its impact has been mainly focused on clinical outcome measures and rarely on health-related quality of life (HRQoL). Aim of the study was to investigate the impact of LTx on HrQoL in IT-IEMs. This single center prospective study involved 32 patients (15 OA, 11 UCD, 6 MSUD; median age at LTx 3.0 years, range 0.8-26.0). HRQoL was assessed pre/post transplantation by PedsQL-General Module 4.0 and by MetabQoL 1.0, a specifically designed tool for IT-IEM. PedsQL highlighted significant post-LTx improvements in total and physical functioning in both patients' and parents' scores. According to age at transplantation (≤3 vs. >3 years), younger patients showed higher post-LTx scores on Physical (p = 0.03), Social (p < 0.001), and Total (p =0.007) functioning. MetabQoL confirmed significant post-LTx changes in Total and Physical functioning in both patients and parents scores (p ≤ 0.009). Differently from PedsQL, MetabQoL Mental (patients p = 0.013, parents p = 0.03) and Social scores (patients p = 0.02, parents p = 0.012) were significantly higher post-LTx. Significant improvements (p = 0.001-0.04) were also detected both in self- and proxy-reports for almost all MetabQoL subscales. This study shows the importance of assessing the impact of transplantation on HrQoL, a meaningful outcome reflecting patients' wellbeing. LTx is associated with significant improvements of HrQol in both self- and parent-reports. The comparison between PedsQL-GM and MetabQoL highlighted that MetabQoL demonstrated higher sensitivity in the assessment of disease-specific domains than the generic PedsQL tool.

Neurologic outcome following liver transplantation for methylmalonic aciduria.

Liver and liver/kidney transplantation are increasingly used in methylmalonic aciduria, but little is known on their impact on CNS. The effect of transplantation on neurological outcome was prospectively assessed in six patients pre- and post-transplant by clinical evaluation and by measuring disease biomarkers in plasma and CSF, in combination with psychometric tests and brain MRI studies. Primary (methylmalonic- and methylcitric acid) and secondary biomarkers (glycine and glutamine) significantly improved in plasma, while they remained unchanged in CSF. Differently, biomarkers of mitochondrial dysfunction (lactate, alanine, and related ratios) significantly decreased in CSF. Neurocognitive evaluation documented significant higher post-transplant developmental/cognitive scores and maturation of executive functions corresponding to improvement of brain atrophy, cortical thickness, and white matter maturation indexes at MRI. Three patients presented post-transplantation reversible neurological events, which were differentiated, by means of biochemical and neuroradiological evaluations, into calcineurin inhibitor-induced neurotoxicity and metabolic stroke-like episode. Our study shows that transplantation has a beneficial impact on neurological outcome in methylmalonic aciduria. Early transplantation is recommended due to the high risk of long-term complications, high disease burden, and low quality of life.

Biomarkers to predict disease progression and therapeutic response in isolated methylmalonic acidemia.

Methylmalonic Acidemia (MMA) is a heterogenous group of inborn errors of metabolism caused by a defect in the methylmalonyl-CoA mutase (MMUT) enzyme or the synthesis and transport of its cofactor, 5'-deoxy-adenosylcobalamin. It is characterized by life-threatening episodes of ketoacidosis, chronic kidney disease, and other multiorgan complications. Liver transplantation can improve patient stability and survival and thus provides clinical and biochemical benchmarks for the development of hepatocyte-targeted genomic therapies. Data are presented from a US natural history protocol that evaluated subjects with different types of MMA including mut-type (N = 91), cblB-type (15), and cblA-type MMA (17), as well as from an Italian cohort of mut-type (N = 19) and cblB-type MMA (N = 2) subjects, including data before and after organ transplantation in both cohorts. Canonical metabolic markers, such as serum methylmalonic acid and propionylcarnitine, are variable and affected by dietary intake and renal function. We have therefore explored the use of the 1-13 C-propionate oxidation breath test (POBT) to measure metabolic capacity and the changes in circulating proteins to assess mitochondrial dysfunction (fibroblast growth factor 21 [FGF21] and growth differentiation factor 15 [GDF15]) and kidney injury (lipocalin-2 [LCN2]). Biomarker concentrations are higher in patients with the severe mut0 -type and cblB-type MMA, correlate with a decreased POBT, and show a significant response postliver transplant. Additional circulating and imaging markers to assess disease burden are necessary to monitor disease progression. A combination of biomarkers reflecting disease severity and multisystem involvement will be needed to help stratify patients for clinical trials and assess the efficacy of new therapies for MMA.

Systematic use of magnetic double J stent in pediatric kidney transplantation: A single-center experience.

BACKGROUND: The intraoperative insertion of a double J stent (DJS) is known to reduce urological complications and is broadly accepted in kidney transplant (KTx) patients. The magnetic ureteral DJS (mDJS) represents a valid alternative device as it can be removed without cystoscopy, using a transurethral magnet. This is of particular importance in the pediatrics, allowing us to avoid cystoscopy requiring general anesthesia (GA) in this population. To date, few data are available on the systematic use of mDJS in pediatric patients undergoing KTx. METHODS: We report a retrospective analysis of 32 consecutive pediatric KTx at our center from July 2020 to December 2021. RESULTS: Ureteral stents remained in place for a median of 35 days (range: 12-76). Non-surgical magnetic removal of the mDJS was attempted in all cases without complications. In most cases (69%), the removal procedure was performed in an outpatient clinic. In 10 cases, the mDJS was removed in the operating room under sedation before removal of the abdominal Tenckhoff catheter. All patients were clinically followed (range: 3-15 months). CONCLUSIONS: We confirm the safety and feasibility of systematic use of mDJS in the setting of pediatric KTx. The systematic use of this device contributes to reduce the need for GA and the rate of hospital admission.

Restless legs syndrome in DNAJC12 deficiency.

BACKGROUND: Restless legs syndrome (RLS) is characterized by an unpleasant or painful sensation generally localized to lower limbs and relieved by movement. Its pathogenesis is hypothesized to involve the dopaminergic system, also in the light of the response of RLS to ex adiuvantibus treatment with dopamine agonists. DNAJC12 deficiency is a recently identified inherited metabolic disease coupling hyperphenylalaninemia to deficient dopaminergic and serotoninergic neurotransmission, due to the combined impairment of the three aromatic amino acids' (i.e., phenylalanine, tyrosine, and tryptophan) hydroxylases. DNAJC12 deficiency was reported in 43 patients so far, presenting with wide spectrum of clinical symptoms. CASE PRESENTATION RESULTS: Here, we report RLS as a novel clinical manifestation of DNAJC12 deficiency, occurring in two adults while on treatment with L-dopa at longitudinal follow-up. The adjunct of low-dose pramipexole was effective in both patients to treat RLS. Besides, this treatment also allowed an improvement of dopaminergic homeostasis, as evidenced by clinical amelioration and stabilization of a peripheral short prolactin profile (a tool to indirectly evaluate dopaminergic homeostasis). DISCUSSION: Besides including RLS as a new treatable clinical manifestation of DNAJC12, these observations may suggest the opportunity of a selective screening for DNAJC12 deficiency in patients with idiopathic RLS.

Allograft Fibrosis After Pediatric Liver Transplantation: Incidence, Risk Factors, and Evolution.

Allograft fibrosis (AF) after pediatric liver transplantation (pLT) is frequent, but its dynamics are unclear. Our aim was to assess the evolution and risk factors of AF after pLT. A retrospective single-center analysis of pLT patients with a follow-up of ≥5 years who underwent protocol liver biopsies at 6 months, 1 year, 2 years, 5 years, and 10 years was performed. Fibrosis was assessed using the METAVIR and Ishak systems and the liver allograft fibrosis score (LAFs). Of 219 pLTs performed from 2008 to 2018, 80 (36.5%) pLTs were included, and 320 biopsies were reviewed. At 6 months after pLT, fibrosis was found in 54 (67.5%) patients by the METAVIR/Ishak systems and in 59 (73.8%) by the LAFs (P = 0.65). By 5 years, AF was detected in 67 (83.8%), 69 (86.3%), and 72 (90%) specimens using the METAVIR, Ishak, and LAFs systems, respectively (P = 0.54); mild (METAVIR, 51 [63.8%]; Ishak, 60 [75%]; LAFs, 65 [81.2%]) and moderate (METAVIR, 16 [20%]; Ishak, 9 [11.9%]; LAFs, 7 [8.8%]) stages were detected, but severe fibrosis was not found (P = 0.09). In the LAFs, fibrosis involved the portal (85%), sinusoidal (15%), and centrolobular (12%) areas. Of 18 patients with 10-year protocol biopsies, AF was present in 16 (90%), including 1 (5.5%) with severe fibrosis. In all systems, 36.3% of patients showed fibrosis progression from 2 years to 5 years after LT, but they remained stable at the 10-year biopsies without clinical implications. In multivariate analysis, only donor age >40 years was a risk factor for moderate AF at 5 years after LT (odds ratio, 8.3; 95% confidence interval, 1.6-42.1, P = 0.01). Cold ischemia time (CIT) >8 hours was associated with portal (P < 0.001)/sinusoidal fibrosis (P = 0.04), donor age >40 years was associated with sinusoidal (P = 0.01)/centrilobular (P = 0.04) fibrosis, and low tacrolimus trough level within 1 year after LT was associated with centrilobular fibrosis (P = 0.02). AF has a high incidence after pLT, occurring early after transplantation. In most cases, AF is mild or moderate and remains stable in the long run without clinical implications. Donor selection, short CIT, and immunosuppression adherence are crucial to reducing the risk of advanced AF.

Renal outcome and plasma methylmalonic acid levels after isolated or combined liver or kidney transplantation in patients with methylmalonic acidemia: A multicenter analysis.

BACKGROUND: Methylmalonic acidemia (MMAemia) is characterized by accumulation of methylmalonic acid (MMA) in all body tissues. To minimize disease-related complications, isolated kidney (KTx), liver (LTx) or combined liver-kidney transplantation (LKTx) have been suggested. However, the impact of these different transplant strategies on outcome are unclear. METHODS: In this multicenter retrospective observational study, we compared plasma MMA levels and estimated glomerular filtration rate (eGFR) data of 83 patients. Sixty-eight patients (82%) had a mut0-type MMAemia, one patient had a mut--type MMAemia, and seven (7.3%) had an inherited defect in cobalamin metabolism (cblA- or cblB-type MMAemia). Median observation period was 3.7 years (0-15.1 years). RESULTS: Twenty-six (31%) patients underwent KTx, 24 (29%) LTx and 33 (40%) LKTx. Posttransplant, mean plasma MMA concentration significantly decreased in all three cohorts; but at month 12, plasma MMA in KTx (1372 ± 1101 µmol/L) was 7.8-fold higher than in LTx (176 ± 103 µmol/L; P < 0.001) and 6.4-fold higher than in LKTx (215 ± 110 µmol/L; P < 0.001). Comparable data were observed at month 24. At time of transplantation, mean eGFR in KTx was 18.1 ± 24.3 mL/min/1.73 m2, in LTx 99.8 ± 29.9 mL/min/1.73 m2, and in LKTx 31.5 ± 21.2 mL/min/1.73 m2. At month 12 posttransplant, mean eGFR in KTx (62.3 ± 30.3 mL/min/1.73 m2) was 33.4% lower than in LTx (93.5 ± 18.3 mL/min/1.73 m2; P = 0.0053) and 25.4% lower than in LKTx (83.5 ± 26.9 mL/min/1.73 m2; P = 0.0403). CONCLUSIONS: In patients with isolated MMAemia, LTx and LKTx lead to markedly lower plasma MMA levels during the first 2 years posttransplant than KTx and are associated with a better preservation of kidney function. LTx should therefore be part of the transplant strategy in MMAemia.

Reversible glomerular damage in disseminated intravascular coagulation.

BACKGROUND: Brain death secondary to traumatic brain injury is one of the main sources of organs for transplantation but it can be associated with disseminated intravascular coagulation, which has been considered a relative contraindication for kidney donation. METHODS: We describe two successful pediatric cases of kidney transplantation from a single donor with disseminated intravascular coagulation. RESULTS: A 17-year-old male donor died from head injury and both kidneys were offered to our center. Within 24 h, donor's Hb and platelets dropped to 8.3 g/dl and 32 000/mcl, respectively, serum creatinine reached 2.01 mg/dl, and urinalysis showed proteinuria (300 mg/dl). Pre-implant biopsy showed massive occlusion of glomerular capillaries by fibrin thrombi containing fragmented red blood cells and inflammatory cells, and acute tubular damage. Arterioles and small arteries were spared. A diagnosis of DIC was made. The kidneys were transplanted in a 16-year-old girl and a 13-year-old boy. Slow recovery of graft function was observed in both recipients. On post-operative day 3, platelets dropped to a minimum value of 66 000 and 86 000/mcl, respectively. Diuresis was always present. On day 4, platelets started to rise. Six months later, both recipients attained normal renal function. A six-month protocol biopsy showed no microthrombi or other signs of disseminated intravascular coagulation. CONCLUSIONS: Despite the limited data available in literature, the outcome of these two cases is positive. Thus, pre-implant kidney biopsy, even if it reveals massive thrombotic occlusion of glomerular capillaries compatible with diagnosis of disseminated intravascular coagulation, should not be considered an absolute contraindication to transplantation.

Liver transplantation in an infant with cerebrotendinous xanthomatosis, cholestasis, and rapid evolution of liver failure.

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a disorder of bile acid (BA) metabolism due to biallelic mutations in CYP27A1. The deposition of cholesterol and cholestanol in multiple tissues results, manifesting as neurologic disease in adults or older children. Neonatal cholestasis (NC) as a presentation of CTX is rare; it may self-resolve or persist, evolving to require liver transplantation (LT). METHODS: We present in the context of similar reports an instance of CTX manifest as NC and requiring LT. RESULTS: A girl aged 4mo was evaluated for NC with normal serum gamma-glutamyl transpeptidase activity. An extensive diagnostic work-up, including liver biopsy, identified no etiology. Rapid progression to end-stage liver disease required LT aged 5mo. The explanted liver showed hepatocyte loss and micronodular cirrhosis. Bile salt export pump (BSEP), encoded by ABCB11, was not demonstrable immunohistochemically. Both severe ABCB11 disease and NR1H4 disease-NR1H4 encodes farsenoid-X receptor, necessary for ABCB11 transcription-were considered. However, selected liver disorder panel sequencing and mass-spectrometry urinary BA profiling identified CTX, with homozygosity for the predictedly pathogenic CYP27A1 variant c.646G > C p.(Ala216Pro). Variation in other genes associated with intrahepatic cholestasis was not detected. Immunohistochemical study of the liver-biopsy specimen found marked deficiency of CYP27A1 expression; BSEP expression was unremarkable. Aged 2y, the girl is free from neurologic disease. CONCLUSIONS: Bile acid synthesis disorders should be routinely included in the NC/"neonatal hepatitis" work-up. The mutually supportive triple approach of BA profiling, immunohistochemical study, and genetic analysis may optimally address diagnosis in CTX, a treatable disease with widely varying presentation.

Minimally invasive hepatopancreatic and biliary surgery in children: a large centre experience and review of the literature.

BACKGROUND: Minimally invasive surgery (MIS) for hepatopancreatic and biliary (HPB) diseases has been widely used in adults, while in children, its application is limited due to its complexity. Herein, we report the experience of MIS for paediatric HPB diseases and literature review. METHODS: All children (≤18 years-old) undergoing major HPB operations by MIS during January 2017-June 2020 in our institution were prospectively enrolled. RESULTS: Out of 139 children operated on for HPB diseases with MIS, 26 (18.7%) patients (age: 11 (1-17) years-old; weight: 41.9 (10.7-75.5) kg) underwent major HPB surgery, including 11 pancreatic resections and 15 liver resections, all performed by a full-laparoscopic-technique. Four (15.3%) surgeries were electively converted to an open-technique for safer operative management. None required a blood transfusion. The median hospital admission was 6 days. Post-operatively, all patients had early mobilization and good recovery. Two (7.7%) patients experienced post-operative complications requiring radiological intervention. Oncological radical resection (R0) was achieved in all tumours, and after 2 years, all children were free of tumour recurrence. CONCLUSION: MIS for HPB surgery is safe and feasible in children, with less surgical trauma, short hospital-stay and better aesthetic results. An adequate learning curve in specialized centres is essential for good outcomes.