Repurposing empagliflozin in individuals with glycogen storage disease Ib: A value-based healthcare approach and systematic benefit-risk assessment

Off-label repurposing of empagliflozin allows pathomechanism-based treatment of neutropenia/neutrophil-dysfunction in glycogen storage disease type Ib (GSDIb). From a value-based healthcare (VBHC) perspective, we here retrospectively studied patient-reported, clinical and pharmacoeconomic outcomes in 11 GSDIb individuals before and under empagliflozin at two centers (the Netherlands [NL], Austria [AT]), including a budget impact analysis, sensitivity-analysis, and systematic benefit-risk assessment. Under empagliflozin, all GSDIb individuals reported improved quality-of-life-scores. Neutrophil dysfunction related symptoms allowed either granulocyte colony-stimulating factor cessation or tapering. Calculated cost savings per patient per year ranged between € 6482-14 190 (NL) and € 1281-41 231 (AT). The budget impact analysis estimated annual total cost savings ranging between € 75 062-225 716 (NL) and € 37 697-231 790 (AT), based on conservative assumptions. The systematic benefit-risk assessment was favorable. From a VBHC perspective, empagliflozin treatment in GSDIb improved personal and clinical outcomes while saving costs, thereby creating value at multiple pillars. We emphasize the importance to reimburse empagliflozin for GSDIb individuals, further supported by the favorable systematic benefit-risk assessment. These observations in similar directions in two countries/health care systems strongly suggest that our findings can be extrapolated to other geographical areas and health care systems.

Hepatic ChREBP orchestrates intrahepatic carbohydrate metabolism to limit hepatic glucose 6-phosphate and glycogen accumulation in a mouse model for acute Glycogen Storage Disease type Ib

OBJECTIVE

Carbohydrate Response Element Binding Protein (ChREBP) is a glucose 6-phosphate (G6P)-sensitive transcription factor that acts as a metabolic switch to maintain intracellular glucose and phosphate homeostasis. Hepatic ChREBP is well-known for its regulatory role in glycolysis, the pentose phosphate pathway, and de novo lipogenesis. The physiological role of ChREBP in hepatic glycogen metabolism and blood glucose regulation has not been assessed in detail, and ChREBP's contribution to carbohydrate flux adaptations in hepatic Glycogen Storage Disease type 1 (GSD I) requires further investigation.

METHODS

The current study aimed to investigate the role of ChREBP as a regulator of glycogen metabolism in response to hepatic G6P accumulation, using a model for acute hepatic GSD type Ib. The immediate biochemical and regulatory responses to hepatic G6P accumulation were evaluated upon G6P transporter inhibition by the chlorogenic acid S4048 in mice that were either treated with a short hairpin RNA (shRNA) directed against ChREBP (shChREBP) or a scrambled shRNA (shSCR). Complementary stable isotope experiments were performed to quantify hepatic carbohydrate fluxes in vivo.

RESULTS

ShChREBP treatment normalized the S4048-mediated induction of hepatic ChREBP target genes to levels observed in vehicle- and shSCR-treated controls. In parallel, hepatic shChREBP treatment in S4048-infused mice resulted in a more pronounced accumulation of hepatic glycogen and further reduction of blood glucose levels compared to shSCR treatment. Hepatic ChREBP knockdown modestly increased glucokinase (GCK) flux in S4048-treated mice while it enhanced UDP-glucose turnover as well as glycogen synthase and phosphorylase fluxes. Hepatic GCK mRNA and protein levels were induced by shChREBP treatment in both vehicle- and S4048-treated mice, while glycogen synthase 2 (GYS2) and glycogen phosphorylase (PYGL) mRNA and protein levels were reduced. Finally, knockdown of hepatic ChREBP expression reduced starch domain binding protein 1 (STBD1) mRNA and protein levels while it inhibited acid alpha-glucosidase (GAA) activity, suggesting reduced capacity for lysosomal glycogen breakdown.

CONCLUSIONS

Our data show that ChREBP activation controls hepatic glycogen and blood glucose levels in acute hepatic GSD Ib through concomitant regulation of glucose phosphorylation, glycogenesis, and glycogenolysis. ChREBP-mediated control of GCK enzyme levels aligns with corresponding adaptations in GCK flux. In contrast, ChREBP activation in response to acute hepatic GSD Ib exerts opposite effects on GYS2/PYGL enzyme levels and their corresponding fluxes, indicating that GYS2/PYGL expression levels are not limiting to their respective fluxes under these conditions.

[Clinical characteristics and genetic analysis of a Chinese pedigree affected by glycogen storage disease type Ia with gout as the first manifestation]

OBJECTIVE

To explore the clinical and genetic characteristics of a Chinese pedigree affected by glycogen storage disease (GSD) type Ia with gout as the first manifestation.

METHODS

Clinical and biochemical data of the pedigree were collected. Available members of the pedigree were subjected to gene sequencing, and the result was analyzed by bioinformatics software. The pedigree was followed up for five years.

RESULTS

The proband was a young female manifesting recurrent gout flare, hypoglycemia, and hypertriglyceridemia. One of her younger brothers also presented with dysplasia and hepatic adenoma. Gene sequencing revealed that the proband and her younger brother both harbored c.1022T>A (p.I1e341Asn) and c.230+5G>A compound heterozygous variants of the G6PC gene , which were inherited from their father and mother, respectively. Among these, the c.230+5G>A is an intron region variant which was unreported previously, and bioinformatics analysis showed that it may impact mRNA splicing of the gene. The proband was treated with raw corn starch, allopurinol, and fenofibrate. Gout was well controlled, and she had given birth to a baby girl without GSD.

CONCLUSION

GSD Ia should be considered among young gout patients with hypoglycemia and hepatomegaly, for which gene sequencing is warranted. GSD Ia has a good prognosis after comprehensive treatment with diet and medicine.

A Prospective Study on Continuous Glucose Monitoring in Glycogen Storage Disease Type Ia: Toward Glycemic Targets

CONTEXT

Although previous research has shown the benefit of continuous glucose monitoring (CGM) for hepatic glycogen storage diseases (GSDs), current lack of prospectively collected CGM metrics and glycemic targets for CGM-derived outcomes in the hepatic GSD population limits its use.

OBJECTIVE

To assess CGM metrics for glycemic variation and glycemic control in adult patients with GSDIa as compared to matched healthy volunteers.

DESIGN

Prospective CGM data were collected during the ENGLUPRO GSDIa trial (NCT04311307) in which a Dexcom G6 device was used. Ten adult patients with GSDIa and 10 age-, sex- and body mass index-matched healthy volunteers were enrolled. Capillary blood glucose was concurrently measured during 2 standardized 2-hour time intervals. Descriptive [eg, glycemic variability (GV), time below range, time in range (TIR), time above range (TAR)] and advanced (ie, first- and second-order derivatives, Fourier analysis) CGM outcomes were calculated. For each descriptive CGM outcome measure, 95% CIs were computed in patients with GSDIa and healthy volunteers, respectively.

RESULTS

CGM overestimation was higher under preprandial and level 1 hypoglycemia (ie, capillary glucose values ≥ 3.0 mmol/L and < 3.9 mmol/L) conditions. GV and TAR were higher while TIR was lower in patients with GSDIa compared to healthy volunteers (P < 0.05). Three patients with GSDIa showed descriptive CGM outcomes outside the calculated 95% CI in GSDIa patients. Advanced CGM analysis revealed a distinct pattern (ie, first- and second-order derivatives and glucose curve amplitude) in each of these 3 patients within the patients group.

CONCLUSIONS

This is the first study to prospectively compare CGM outcomes between adult patients with GSDIa and matched healthy volunteers. The generation of a set of CGM metrics will provide guidance in using and interpreting CGM data in GSDIa and will be useful for the definition of glycemic targets for CGM in patients with GSDIa. Future studies should investigate the prognostic value of CGM outcomes and their major determinants in patients with GSDIa.

Molecular and clinical profiling in a large cohort of Asian Indians with glycogen storage disorders

Glycogen storage disorders occur due to enzyme deficiencies in the glycogenolysis and gluconeogenesis pathway, encoded by 26 genes. GSD’s present with overlapping phenotypes with variable severity. In this series, 57 individuals were molecularly confirmed for 7 GSD subtypes and their demographic data, clinical profiles and genotype-phenotype co-relations are studied. Genomic DNA from venous blood samples was isolated from clinically affected individuals. Targeted gene panel sequencing covering 23 genes and Sanger sequencing were employed. Various bioinformatic tools were used to predict pathogenicity for new variations. Close parental consanguinity was seen in 76%. Forty-nine pathogenic variations were detected of which 27 were novel. Variations were spread across GSDIa, Ib, III, VI, IXa, b and c. The largest subgroup was GSDIII in 28 individuals with 24 variations (12 novel) in AGL. The 1620+1G>C intronic variation was observed in 5 with GSDVI (PYGL). A total of eleven GSDIX are described with the first Indian report of type IXb. This is the largest study of GSDs from India. High levels of consanguinity in the local population and employment of targeted sequencing panels accounted for the range of GSDs reported here.

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.

Secondary diabetes as a rare complication of glycogen storage disease 1a: case report and review of literature

Glycogen storage diseases (GSDs) are disorders of carbohydrate metabolism and hypoglycemia is their hallmark. Secondary diabetes with glycogen storage disease, which seems rather paradoxical, has been rarely reported. A 13-year-old girl previously diagnosed to have GSD 1a presented to the emergency with multiple episodes of vomiting and loss of consciousness. She had hyperglycemia, ketonuria, hyperlactatemia and metabolic acidosis, suggestive of diabetic ketosis with acidosis possibly contributed by both high serum lactate and serum ketones. Her glycated hemoglobin was high, with detectable serum insulin levels, which suggested secondary diabetes in the background of GSD Ia. Her management posed a therapeutic challenge. She was managed with insulin and achieved good glycemic control. We wish to conclude that GSD may rarely lead to secondary diabetes as a complication and the management is complex owing to the nature of the disease. Insulin remains the mainstay of the treatment.

Tumorigenic Potential of Granulocyte Colony-Stimulating Factor Therapy-A Case Report and Review of Literature

An association between granulocyte colony-stimulating factor therapy (G-CSFT) in patients with glycogen storage disease type Ib (GSDIb) and the development of giant cell lesions of the maxillofacial complex has emerged. We have reported, to the best of our knowledge, the fourth case of giant cell granuloma (GCG) in a patient with GSDIb undergoing G-CSFT. GSDIb can present with hypoglycemia, hypertriglyceridemia, and neutropenia. G-CSFT has often been used in the treatment of recurrent infections or sepsis caused by neutropenia and to treat inflammatory bowel disease and diarrhea. The current reported data are lacking in both the association and the potential causation of G-CSFT and the development of giant cell tumors. Given the prevalence of GSDIb and its therapy, oral and maxillofacial surgeons should be aware of the tumorigenic potential of G-CSFT in patients with GSDIb. In the present report, we have described the case of a 17-year-old patient with GSDIb undergoing GCSFT who presented with a peripheral and central GCG. She was treated but presented again 13 months later with concerns for a new primary lesion. We have also discussed GSDIb, G-CSFT, and the current data, highlighting the association between G-CSFT for GSDIb, the potential mechanism of GCG development, the use of adjuvant therapy, and the need for close follow-up of this population. The purpose of the present case report is to highlight the presentation, management, and follow-up of giant cell lesions in patients with GSDIb treated with G-CSFT.

Antiviral effect of epigallocatechin gallate on enterovirus 71

Oxidative stress is known to be a determinant of a host's susceptibility to pathogens. Natural compounds with antioxidant activity may provide a preventive measure against infection. Tea polyphenols were evaluated for their ability to inhibit enterovirus 71 (EV71) replication in Vero cell culture. Among the polyphenolic compounds tested, epigallocatechin gallate (EGCG) and gallocatechin gallate (GCG) potently inhibited replication of EV71. EGCG and GCG reduced the titer of infectious progeny virus by 95%. Quantitative RT-PCR analysis also revealed that EGCG suppressed replication of genomic RNA. It was accompanied by an increased cytoprotective effect. EGCG and GCG caused 5-fold increase in the viability of EV71-infected cells. The viral inhibitory effect correlated well with the antioxidant capacity of polyphenol. Mechanistically, EV71 infection led to increased oxidative stress, as shown by increased dichlorofluorescein and MitoSOX Red fluorescence. Upon EGCG treatment, reactive oxygen species (ROS) generation was significantly reduced. Consistent with this, EV71 replication was enhanced in glucose-6-phosphate dehydrogenase deficient cells, and such enhancement was largely reversed by EGCG. These findings suggest that EGCG may suppress viral replication via modulation of cellular redox milieu.

Safety of the methylene blue plus chloroquine combination in the treatment of uncomplicated falciparum malaria in young children of Burkina Faso [ISRCTN27290841]

Background

Safe, effective and affordable drug combinations against falciparum malaria are urgently needed for the poor populations in malaria endemic countries. Methylene blue (MB) combined with chloroquine (CQ) has been considered as one promising new regimen.

Objectives

The primary objective of this study was to evaluate the safety of CQ-MB in African children with uncomplicated falciparum malaria. Secondary objectives were to assess the efficacy and the acceptance of CQ-MB in a rural population of West Africa.

Methods

In this hospital-based randomized controlled trial, 226 children (6–59 months) with uncomplicated falciparum malaria were treated in Burkina Faso. The children were 4:1 randomized to CQ-MB (n = 181; 25 mg/kg CQ and 12 mg/kg MB over three days) or CQ (n = 45; 25 mg/kg over three days) respectively. The primary outcome was the incidence of severe haemolysis or other serious adverse events (SAEs). Efficacy outcomes were defined according to the WHO 2003 classification system. Patients were hospitalized for four days and followed up until day 14.

Results

No differences in the incidence of SAEs and other adverse events were observed between children treated with CQ-MB (including 24 cases of G6PD deficiency) compared to children treated with CQ. There was no case of severe haemolysis and also no significant difference in mean haemoglobin between study groups. Treatment failure rates were 53.7% (95% CI [37.4%; 69.3%]) in the CQ group compared to 44.0% (95% CI [36.3%; 51.9%]) in the CQ-MB group.

Conclusion

MB is safe for the treatment of uncomplicated falciparum malaria, even in G6PD deficient African children. However, the efficacy of the CQ-MB combination has not been sufficient at the MB dose used in this study. Future studies need to assess the efficacy of MB at higher doses and in combination with appropriate partner drugs.

Genetic renal disease

Many genetic renal disease now have specific genetic definitions, allowing prognostication. Several glomerular basement membrane defects include Alport's syndrome and benign familial hematurias. Genetic tubular or interstitial structural defects likely include familial juvenile nephronophthisis, as well as the polycystic diseases. Hereditary metabolic diseases can result in storage processes and circulating lipid disorders, which result in progressive glomerular sclerosis. Hereditary metabolic errors result in products causing obstruction and interstitial damage. Other hereditary disorders cause hemodynamic process that result in renal damage. The vascular structural defects of Marfan syndrome, Alagille syndrome, neurofibromatosis, and Cockayne's syndrome can secondarily result in renal vascular destruction. An awareness of these hereditary disease pathways to renal disease is essential to primary care pediatrics.

Dynamic MR imaging of hepatic adenomas with pathologic correlation

Two patients with hepatic adenomas (HAs) were evaluated using dynamic magnetic resonance (MR) imaging. Findings of conventional MR imaging of HAs have varied according to reports in the literature, and dynamic MR imaging of HAs has not been previously reported. Dynamic MR imaging using Gd-DTPA showed homogeneous enhancement in the early dynamic phase and prolonged enhancement in the late phase in the typical HA of Case 2. The HA of Case 1 contained fibrosis and exhibited delayed enhancement. The opacification of contrast enhancement was homogeneous and did not occur from the peripheral region as is observed in typical hemangiomas. In addition, washout of contrast material was not as rapid as with typical hepatocellular carcinomas (HCCs).

Controlled clinical evaluations of chlorine dioxide, chlorite and chlorate in man

To assess the relative safety of chronically administered chlorine water disinfectants in man, a controlled study was undertaken. The clinical evaluation was conducted in the three phases common to investigational drug studies. Phase I, a rising dose tolerance investigation, examined the acute effects of progressively increasing single doses of chlorine disinfectants to normal healthy adult male volunteers. Phase II considered the impact on normal subjects of daily ingestion of the disinfectants at a concentration of 5 mg/l. for twelve consecutive weeks. Persons with a low level of glucose-6-phosphate dehydrogenase may be expected to be especially susceptible to oxidative stress; therefore, in Phase III, chlorite at a concentration of 5 mg/l. was administered daily for twelve consecutive weeks to a small group of potentially at-risk glucose-6-phosphate dehydrogenase-deficient subjects. Physiological impact was assessed by evaluation of a battery of qualitative and quantitative tests. The three phases of this controlled double-blind clinical evaluation of chlorine dioxide and its potential metabolites in human male volunteer subjects were completed uneventfully. There were no obvious undesirable clinical sequellae noted by any of the participating subjects or by the observing medical team. In several cases, statistically significant trends in certain biochemical or physiological parameters were associated with treatment; however, none of these trends was judged to have physiological consequence. One cannot rule out the possibility that, over a longer treatment period, these trends might indeed achieve proportions of clinical importance. However, by the absence of detrimental physiological responses within the limits of the study, the relative safety of oral ingestion of chlorine dioxide and its metabolites, chlorite and chlorate, was demonstrated.

Anaesthesia in Von Gierke's disease. Current approach to management

A case report of a patient with Von Gierke's (glycogen storage disease Cori type (1)1 disease who required femoral osteotomy is presented. Current techniques of management of this condition which are likely to improve the outcome of general anaesthesia and surgery are discussed.

Von Gierke's disease: report of case

Von Gierke's disease, or hepatorenal glycogenesis, type I, presents an interesting challenge to the dental practitioner. Showing an incidence of 1/400,000, it is a fairly rare occurrence. It indicates the importance of proper medical consultation in treating these children, and proper dental treatment and preventive programs to alleviate what could be dangerous for these patients.

Hemoglobin E and glucose-6-phosphate deficiency in the Khmer Air Force (Cambodia)

This study was designed to investigate the use of primaquine in malaria control in the Khmer Republic (Cambodia). Blood was drawn from 106 male Khmer Air Force troops for analysis of hemoglobin E and glucose-6-phosphate (G-6-PD) deficiency. A test group of 15 men with G-6-PD deficiency and a group of 31 normal controls were given 15 mg of primaquine each morning for 14 days. The patients were followed for hemoglobinuria and changes in hematocrit. Primaquine induced a significant, but not a dangerous, hemolysis in G-6pD-deficient Khmer troops. The G-6-PD deficiency seen in Khmer Air Force subjects was G-6-PD Mahidol. Statistically, G-6-PD Mahidol was linked to hemoglobin E.

[Various enzymes of isolated nuclear membranes and cell nuclei of the liver and hepatoma 27 of rats]

A comparative study of glucose-6-phosphatase, alcaline RNase, ATPase, inosine diphosphatase and 5'-nucleotidase activities in isolated rat liver and hepatoma-27 nuclei and nuclear envelopes was performed. The tumor nuclear membranes were shown to be free from G-6-Pase activity in contrast to the liver nuclear membranes. The nuclear RNase activity was strongly inhibited in the hepatoma and could be unmasked in the presence of 3-10(-4) M pCMB. Hepatoma nuclear and nuclear envelopes ATP-ase activity was found to be moderately decreased as compared to those of the normal tissue. The values of inosine diphosphatase activity in hepatoma were similar to those in liver. The role of the nuclear envelope in nuclear-cytoplasmic interactions as well as nuclear location of G-6-Pase are discussed.

[Congenital enzyme deficiency in carbohydrate metabolism. Its significance for clinical pediatrics and human biochemical genetics (author's transl)]

A review of the enzyme deficiencies of carbohydrate metabolism known at the present time is given. Through prominent clinical symptoms and consideration of food as a pathological agent, it is possible to suspect the various diseases before the results of the biochemical determinations are available. On account of the sometimes striking course, therapy can consequently be started at the earliest possible moment.

Hyperlipidaemia in children

Hyperlipidaemia in children is most commonly expressed as hypercholesterolaemia. "Normal values" for serum cholesterol, if defined statistically, vary between communities, and levels of cholesterol in childhood above which an increased risk of coronary heart disease in adult life may be expected have not been firmly established. It is suggested that serum cholesterol concentration over 250 mg/dl (6.47 mmol/l) in a child over 1 year of age merits detailed investigation, including full lipoprotein analysis, and levels of serum cholesterol between230 and 250 mg/dl (5.95-6.47 mmol/l) should be repeated with further studies if indicated. Secondary hyperlipoproteinaemia rarely presents diagnostic problems but must always be excluded. The only primary hyperlipoproteinaemia likely to be encountered in childhood is familial hyperbetalipoproteinaemia in its common heterozygous form. The most effective means to date of lowering serum cholesterol in this condition is cholestyramine, but the long-term consequences of therapy are not known and treatment should at present be limited to children from high-risk families. Long-term follow-up is essential and until results of such studies are available population screening is unjustified.