Long-term complications of glycogen storage disease type Ia in the canine model treated with gene replacement therapy.

Conference Paper

BACKGROUND: Glycogen storage disease type Ia (GSD Ia) in dogs closely resembles human GSD Ia. Untreated patients with GSD Ia develop complications associated with glucose-6-phosphatase (G6Pase) deficiency. Survival of human patients on intensive nutritional management has improved; however, long-term complications persist including renal failure, nephrolithiasis, hepatocellular adenomas (HCA), and a high risk for hepatocellular carcinoma (HCC). Affected dogs fail to thrive with dietary therapy alone. Treatment with gene replacement therapy using adeno-associated viral vectors (AAV) expressing G6Pase has greatly prolonged life and prevented hypoglycemia in affected dogs. However, long-term complications have not been described to date. METHODS: Five GSD Ia-affected dogs treated with AAV-G6Pase were evaluated. Dogs were euthanized due to reaching humane endpoints related to liver and/or kidney involvement, at 4 to 8 years of life. Necropsies were performed and tissues were analyzed. RESULTS: Four dogs had liver tumors consistent with HCA and HCC. Three dogs developed renal failure, but all dogs exhibited progressive kidney disease histologically. Urolithiasis was detected in two dogs; uroliths were composed of calcium oxalate and calcium phosphate. One affected and one carrier dog had polycystic ovarian disease. Bone mineral density was not significantly affected. CONCLUSIONS: Here, we show that the canine GSD Ia model demonstrates similar long-term complications as GSD Ia patients in spite of gene replacement therapy. Further development of gene therapy is needed to develop a more effective treatment to prevent long-term complications of GSD Ia.

Full Text

Duke Authors

Cited Authors

  • Brooks, ED; Landau, DJ; Everitt, JI; Brown, TT; Grady, KM; Waskowicz, L; Bass, CR; D'Angelo, J; Asfaw, YG; Williams, K; Kishnani, PS; Koeberl, DD

Published Date

  • November 2018

Published In

Volume / Issue

  • 41 / 6

Start / End Page

  • 965 - 976

PubMed ID

  • 30043186

Pubmed Central ID

  • PMC6328337

Electronic International Standard Serial Number (EISSN)

  • 1573-2665

Digital Object Identifier (DOI)

  • 10.1007/s10545-018-0223-y

Conference Location

  • United States