State of the art management practices for liver glycogen storage disorders: Results from an international survey among metabolic centres.

Matthias Gautschi and Michel Hochuli are members of the GSD Collaboration group.

Background
Liver glycogen storage disorders (GSDs) are rare inherited disorders of carbohydrate metabolism that are clinically characterized by hepatomegaly and fasting intolerance. This group of disorders comprises GSD Ia and Ib as well as the so-called ketotic GSDs including GSD III, VI, IX, XI and 0a. Although clinical practice guidelines exist for most GSD subtypes, diagnostics, treatment and monitoring differ significantly among metabolic centres. The aim of this study was to gain insight into current clinical practice for liver GSDs.
Methods
An international web-based survey was performed among health care professionals involved in the care of individuals with liver GSDs.
Results
Sixty-seven respondents from 28 different countries caring for approximately 2650 liver GSD patients completed the survey. While the diagnostic approach was generally consistent, significant differences among metabolic centres are still observed with respect to monitoring parameters and treatment approaches. Reasons for these differences are local availability of management tools and treatment options, the rarity of the different GSD subtypes, the experiences of health care professionals, and the existence of extreme phenotypes.
Conclusion
The development of a standard set of outcomes for patients with liver GSDs is warranted as a reference for both daily care and the evaluation of safety and efficacy of future therapies. For various parameters that serve as valuable outcome measures, tools and target values should be better defined.