Longterm Outcomes of Living Donor Liver Transplantation for Glycogen Storage Disease Type 1b

The Impact of Early Indication of Living Donor Liver Transplantation on the Outcomes of Patients With Propionic Acidemia: A Single-Center Experience

BACKGROUND

Liver transplantation has been indicated for propionic acidemia (PA) patients with frequent metabolic decompensation and performed as an enzyme replacement therapy. We retrospectively evaluated the outcomes of patients with PA and analyze the appropriate timing of living donor liver transplantation (LDLT).

METHODS

We reviewed 12 children with PA who underwent LDLT, who were divided into early (period from the first episode of metabolic decompensation to LDLT < 1 year; n = 6) and late (> 1 year; n = 6) indication groups depending on the timing of LDLT.

RESULTS

The patient and graft survival rates were 100% in 12 children with PA, and the median observation period was 61 months (5-193 months). None of the patients experienced any episodes of metabolic decompensation after LDLT. The timing of LDLT did not influence the incidence of surgical complications. Two patients in the late indication group had episodes of cardiac arrest and long QT syndrome before LDLT, and one patient showed prolongation of QT interval after LDLT. Two of the six patients in the late indication group had findings of metabolic stroke of the brain on MRI before LDLT. Although LDLT improved the findings of metabolic stroke, a decrease in development quotient score was shown in the post-LDLT course.

CONCLUSIONS

LDLT may be an effective therapeutic option for improving metabolic control. Early LDLT might be help prevent cardiomyopathy and neurological impairment.

Outcomes of Pediatric Liver Transplantation in Glycogen Storage Disease Type 1b-A Single-Center Experience

BACKGROUND

Liver transplantation (LT) normalizes fasting tolerance in glycogen storage disease type (GSD) 1b. However, reported outcomes post-LT with respect to correction of neutropenia, infection risk and growth are varied. Sodium-glucose cotransporter-2 (SGLT2) inhibitors have been recently shown to improve neutropenia in GSD1b patients.

METHODS

In this single-center retrospective study, we reviewed all children who underwent LT for GSD1b. Neutropenia, dose of granulocyte colony-stimulating factor (G-CSF), unplanned hospital attendance, anthropometrics, graft rejection, survival, and the effects of dapagliflozin were analyzed. Data from protocol biopsies obtained at 1, 5, and 10 years post-LT and immunosuppression levels were collected.

RESULTS

Eight children (6 female), all on G-CSF pre-transplant, underwent cadaveric LT for GSD1b at median age 3.6 years (IQR 3.3-5.1) with mean follow-up time of 10.3 years (95% CI 7.5-13.1). Neutrophil count and G-CSF requirement did not improve post-LT. Although a reduction in unplanned hospital attendance due to infection (0.98 [95% CI 0.76-1.26] vs. 0.49 [95% CI 0.41 to 0.57] per person-year, p < 0.01) was observed, gastrointestinal complaints and graft dysfunction accounted for a similar hospitalization burden pre- versus post-LT. Body mass index (BMI) reduced post-LT (Z-score 1.47 [95%CI 0.39-2.23] vs. 0.56 [95% CI -0.74 to 1.45], p = 0.02), with no significant change in height. Although all children and grafts have survived, 75% of recipients developed rejection, despite adequate immunosuppression levels, with two children having been found to have developed significant fibrosis on their 5-year protocol biopsy. Although dapagliflozin allowed cessation of G-CSF, no improvement in neutrophil count was observed. Despite this, a reduction in gastrointestinal and infection-related morbidity was noted following dapagliflozin.

CONCLUSION

Although LT normalizes fasting tolerance in GSD1b and reduces hospital attendance due to infection, morbidity from infection and gastrointestinal manifestations persist. Children in our cohort experienced high rates of rejection necessitating titration of immunosuppression to balance risk of infection against organ rejection. Future studies should investigate whether early introduction of SGLT2 inhibitors post-LT impact morbidity in this group.

Long-term Outcomes of Liver Transplantation for Inborn Errors of Metabolism in Children

BACKGROUND

Liver transplantation for inborn errors of metabolism is increasingly common and has historically had positive outcomes. However, this therapeutic modality is not without risks, and patient post-transplant quality of life should be part of the consideration.

METHODS

This retrospective, observational cohort study included all pediatric patients receiving liver transplant from 2010 through 2020 at a single center. Recipients were split into 2 groups based on metabolic or non-metabolic indications for liver transplant. Ten-year patient survival and graft survival were analyzed. The PedsQL Transplant Module and RAND 36-Item Health Survey 1.0 were administered prospectively to those recipients with metabolic indications.

RESULTS

Ten-year patient survival was statistically significantly higher in the metabolic group than in the non-metabolic (p < .05), and there was no difference in 10-year graft survival between groups. Of the 12 patients in the metabolic group who completed the PedsQL Transplant Module or RAND 36-Item Health Survey 1.0, the median score was 88, similar to the score seen in healthy children.

CONCLUSIONS

Liver transplantation for inborn errors of metabolism provides excellent long-term outcomes in terms of patient and graft survival, while maintaining a high quality of life.

Current status and future directions of liver transplantation for metabolic liver disease in children

Orthotopic liver transplantation (OLT) in the care of children with inborn errors of metabolism (IEM) is well established and represent the second most common indication for pediatric liver transplantation in most centers worldwide, behind biliary atresia. OLT offers cure of disease when a metabolic defect is confined to the liver, but may still be transformative on a patient's quality of life reducing the chance of metabolic crises causing neurological damage in children be with extrahepatic involvement and no "functional cure." Outcomes post-OLT for inborn errors of metabolism are generally excellent. However, this benefit must be balanced with consideration of a composite risk of morbidity, and commitment to a lifetime of post-transplant chronic disease management. An increasing number of transplant referrals for children with IEM has contributed to strain on graft access in many parts of the world. Pragmatic evaluation of IEM referrals is essential, particularly pertinent in cases where progression of extra-hepatic disease is anticipated, with long-term outcome expected to be poor. Decision to proceed with liver transplantation is highly individualized based on the child's dynamic risk-benefit profile, their family unit, and their treating multidisciplinary team. Also to be considered is the chance of future treatments, such as gene therapies, emerging in the medium term.

Glycogen storage diseases

Glycogen storage diseases (GSDs) are a group of rare, monogenic disorders that share a defect in the synthesis or breakdown of glycogen. This Primer describes the multi-organ clinical features of hepatic GSDs and muscle GSDs, in addition to their epidemiology, biochemistry and mechanisms of disease, diagnosis, management, quality of life and future research directions. Some GSDs have available guidelines for diagnosis and management. Diagnostic considerations include phenotypic characterization, biomarkers, imaging, genetic testing, enzyme activity analysis and histology. Management includes surveillance for development of characteristic disease sequelae, avoidance of fasting in several hepatic GSDs, medically prescribed diets, appropriate exercise regimens and emergency letters. Specific therapeutic interventions are available for some diseases, such as enzyme replacement therapy to correct enzyme deficiency in Pompe disease and SGLT2 inhibitors for neutropenia and neutrophil dysfunction in GSD Ib. Progress in diagnosis, management and definitive therapies affects the natural course and hence morbidity and mortality. The natural history of GSDs is still being described. The quality of life of patients with these conditions varies, and standard sets of patient-centred outcomes have not yet been developed. The landscape of novel therapeutics and GSD clinical trials is vast, and emerging research is discussed herein.

Glycogen storage diseases: An update

Glycogen storage diseases (GSDs), also referred to as glycogenoses, are inherited metabolic disorders of glycogen metabolism caused by deficiency of enzymes or transporters involved in the synthesis or degradation of glycogen leading to aberrant storage and/or utilization. The overall estimated GSD incidence is 1 case per 20000-43000 live births. There are over 20 types of GSD including the subtypes. This heterogeneous group of rare diseases represents inborn errors of carbohydrate metabolism and are classified based on the deficient enzyme and affected tissues. GSDs primarily affect liver or muscle or both as glycogen is particularly abundant in these tissues. However, besides liver and skeletal muscle, depending on the affected enzyme and its expression in various tissues, multiorgan involvement including heart, kidney and/or brain may be seen. Although GSDs share similar clinical features to some extent, there is a wide spectrum of clinical phenotypes. Currently, the goal of treatment is to maintain glucose homeostasis by dietary management and the use of uncooked cornstarch. In addition to nutritional interventions, pharmacological treatment, physical and supportive therapies, enzyme replacement therapy (ERT) and organ transplantation are other treatment approaches for both disease manifestations and long-term complications. The lack of a specific therapy for GSDs has prompted efforts to develop new treatment strategies like gene therapy. Since early diagnosis and aggressive treatment are related to better prognosis, physicians should be aware of these conditions and include GSDs in the differential diagnosis of patients with relevant manifestations including fasting hypoglycemia, hepatomegaly, hypertransaminasemia, hyperlipidemia, exercise intolerance, muscle cramps/pain, rhabdomyolysis, and muscle weakness. Here, we aim to provide a comprehensive review of GSDs. This review provides general characteristics of all types of GSDs with a focus on those with liver involvement.

Liver transplantation in glycogen storage disease type Ib: The role of SGLT2 inhibitors

We report on liver transplantation in two patients with GSD Ib on treatment with empagliflozin. The use of this SGLT2 inhibitor resulted in a marked decrease of 1,5-anhydroglucitol which has an important role in the development of neutropenia in this condition. As intended, this caused a significant rise of neutrophil numbers. Liver transplantation alone did not produce the desired effect and our observation argues for continuing SGLT2 inhibitor treatment after transplantation.

Outcome of liver transplantation in hepatic glycogen storage disease: A systematic review and meta-analysis

INTRODUCTION

Liver transplantation (LT) is the choice of therapeutic option for end-stage hepatic GSD patients; however, reports about the long-term outcome of LT in these patients have remained controversial.

METHODS

We performed a systematic review and meta-analysis of observational studies published until Dec 31, 2021, that investigated the long-term outcome of LT in hepatic GSD patients. A literature search in the MEDLINE/PubMed, EMBASE,Cochrane Library, Scopus and Web of Science Core Collection databases was performed.

RESULTS

14 studies with 210 patients were included in our analysis. As the results showed, the pooled proportion of GSD patients with complications after liver transplant (e.g., hemorrhagic shock, biliary complications, tacrolimus encephalopathy, chronic hepatitis, hepatic artery thrombosis, hepatic adenoma, sepsis, liver dysfunction, chronic rejection, acute cellular rejection, and CMV infection) was 27.7% (95% CI: 20.42-35.67) without heterogeneity (I²  = 24.04%), as calculated by the random-effect model. The pooled proportion of GSD patients with complications related to GSD after LT, including HCC (Hepatocellular carcinoma), renal complication, muscle problems, delayed menarche, persistent neutropenia, pneumonitis, renal failure, and hepatic adenoma was 22.2% (95% CI: 7.97-40.01) with high heterogeneity (I²  = 82.47%). Subgroup analysis including the age of patients (adult/pediatric), duration of follow-up, and type of donor was conducted to investigate the resources of heterogeneity.

CONCLUSION

According to our investigation and review analysis, most GSD patients showed significant outcome improvement after liver transplantation. Overall, our findings showed an excellent outcome of liver transplantation in GSD patients; however, it needs further investigations to be confirmed.

Liver transplantation in glycogen storage disease: a single-center experience

Background

Glycogen storage diseases (GSDs) are inherited glycogen metabolic disorders which have various subtypes. GSDs of type I, III, IV, VI, and IX show liver involvement and are considered as hepatic types of GSDs. Thus, liver transplantation (LT) has been proposed as a final therapy for these types of GSD. LT corrects the primary hepatic enzyme defect; however, the long-term outcomes of LT in these patients have not been extensively evaluated so far. There are few reports in the English literature about the outcome of GSD patients after LT. There has been no report from Iran. The present retrospective study aimed to evaluate the long-term outcomes of eight patients with GSD types I, III, and IV who underwent LT in the affiliated hospitals of Shiraz University of Medical Sciences, from March 2013 to June 2021. During this period, there were no patients with GSD VI and IX identified in this center.

Results

The median time of diagnosis of the GSDs and at transplant was 1 year and 11 years, respectively. All eight transplanted patients were alive at the time of follow-up in this study. None of them required a re-transplant. All of the patients showed normalized liver enzymes after LT with no sign of hypoglycemia.

Conclusions

LT is an achievable treatment for end-stage hepatic involvement of GSDs with a cure for metabolic deficiency. Our experience in these eight patients shows a favorable outcome with no mortality and no major complication.

Immunological features and complications in patients with glycogen storage disease 1b after living donor liver transplantation

BACKGROUND

LT is an elective treatment choice for children diagnosed with GSD1b that can improve their quality of life and stabilize their glucose intolerance. However, careful attention should be paid to immunosuppression after LT due to the susceptibility to infection because of neutropenia and neutrophil dysfunction in GSD1b patients. This study revealed the immunological features and complications in the early post-LT period.

METHODS

We compared findings between 11 (1.9%) children with GSD1b and 273 children with BA. Analyses using the PSM were performed to overcome selection bias.

RESULTS

Despite persistent low tacrolimus trough levels in GSD1b patients, none of these children developed TCMR within 1 month after LDLT (GSD1b: 0/11 [0%] vs. BA: 86/273 [31.5%], p = .038). This result was also confirmed in PSM. The incidence of bloodstream infections was higher in GSD1b patients than in BA patients in the early phase of the post-transplant period (GSD1b: 4/11 [36.4%] vs. BA: 33/273 [12.1%], p = .041), but not reach statistical significance in PSM. In a phenotypic analysis, the ratio of CD8⁺ T cells in GSD1b recipients' peripheral blood mononuclear cell samples was lower than in recipients with BA through the first month after LDLT.

CONCLUSIONS

We found that GSD1b recipients were more likely to develop postoperative bloodstream infection than recipients with BA but did not experience TCMR despite low tacrolimus levels in the early post-LDLT period. A tailored immunosuppression protocol should be prepared for GSD1b recipients after LDLT.

Modifiable factors affecting renal preservation in type I glycogen storage disease after liver transplantation: a single-center propensity-match cohort study

BACKGROUND AND AIMS

Glycogen storage disease type I (GSD-I) is an autosomal recessive disorder of carbohydrate metabolism, resulting in limited production of glucose and excessive glycogen storage in the liver and kidneys. These patients are characterized by life-threatening hypoglycemia, metabolic derangements, hepatomegaly, chronic kidney disease, and failure to thrive. Liver transplantation (LT) has been performed for poor metabolic control and delayed growth. However, renal outcome was diverse in pediatric GSD patients after LT. The aim of this study was to investigate the long-term outcome of renal function in pediatric GSD-I patients after living donor LT (LDLT), and to identify modifiable variables that potentially permits LT to confer native renal preservation.

METHODS

The study included eight GSD-Ia and one GSD-Ib children with a median age of 9.0 (range 4.2-15.7) years at the time of LT. Using propensity score matching, 20 children with biliary atresia (BA) receiving LT were selected as the control group by matching for age, sex, pre-operative serum creatinine (SCr) and pediatric end-stage liver disease (PELD) score. Renal function was evaluated based on the SCr, estimated glomerular filtration rate (eGFR), microalbuminuria, and morphological changes in the kidneys. Comparability in long-term renal outcome in terms of anatomic and functional parameters will help to identify pre-LT factors of GSD-I that affect renal prognosis.

RESULTS

The clinical and biochemical characteristics of the GSD and BA groups were similar, including immunosuppressive regimens and duration of follow-up (median 15 years) after LT. Overall, renal function, including eGFR and microalbuminuria was comparable in the GSD-I and BA groups (median eGFR: 111 vs. 123 ml/min/1.73m2, P = 0.268; median urine microalbuminuria to creatinine ratio: 16.0 vs. 7.2 mg/g, P = 0.099, respectively) after LT. However, in the subgroups of the GSD cohort, patients starting cornstarch therapy at an older age (≥ 6-year-old) before transplantation demonstrated a worse renal outcome in terms of eGFR change over years (P < 0.001). In addition, the enlarged kidney in GSD-I returned to within normal range after LT.

CONCLUSIONS

Post-LT renal function was well-preserved in most GSD-I patients. Early initiation of cornstarch therapy before preschool age, followed by LT, achieved a good renal prognosis.

Long-term outcome after liver transplantation in children with type 1 glycogen storage disease

Patients with GSD type 1 (von Gierke disease) are initially managed medically to maintain normoglycemia. However, if they do not achieve good metabolic control, LT is then considered. We describe the long-term outcome of 6 children with GSD type 1 who underwent LT. Retrospective chart review of the data of 6 children with GSD type 1 who underwent LT at National University Hospital, Singapore, from May 1998 to October 2018, was performed. The median (IQR) age at diagnosis of the GSD was 1 year (0.92-5.50) and at transplant was 13.88 years (11.46-16.38). All of the patients had elevated liver enzymes, hypercholesterolemia, hypertriglyceridemia, and hyperlactatemia prior to transplant. All of the patients are alive at the time of analysis and follow-up. None of them required a re-transplant. For the three patients who had hypoglycemia pretransplant, there was no recurrence post-transplant. All of the patients had normalization of liver enzymes by 1 year post-transplant. Long-term outcome of patients with GSD who underwent LT has been positive with improvement in metabolic control for most patients. We report the unusual finding of two siblings with persistent hyperuricemia post-transplant requiring allopurinol.