What is the management plan for glycogen storage disease?

From the Guidelines

The management plan for glycogen storage disease (GSD) should focus on maintaining stable blood glucose levels and preventing metabolic complications, with the cornerstone of treatment being frequent feeding with complex carbohydrates, typically cornstarch (1-2 g/kg every 4-6 hours) for children and adults with GSD types I and III, as recommended by 1. The goal of treatment is to prevent hypoglycemia, promote normal growth and development, and manage long-term complications. Key aspects of dietary management include:

• Frequent feeding with complex carbohydrates, such as cornstarch, to maintain stable blood glucose levels
• Avoiding simple sugars and limiting fructose and galactose, especially in GSD type I
• Ensuring adequate protein intake, with 2-3 g/kg/day recommended for children with GSD type III, as noted in 1 Regular monitoring of blood glucose levels is essential, with target levels above 70 mg/dL (3.9 mmol/L), and long-term complications require monitoring and management, including regular assessment of liver function, kidney function, and growth parameters, as outlined in 1 and 1. Some patients may benefit from medications like allopurinol for hyperuricemia or lipid-lowering agents for hypertriglyceridemia, as mentioned in 1 and 1. A multidisciplinary team approach, including a metabolic disease specialist, cardiologist, neuromuscular specialist, gastroenterologist, and metabolic dietitian, is recommended for the management of GSD, as emphasized in 1 and 1. Overall, a comprehensive approach to management is necessary to prevent metabolic derangements and promote optimal outcomes for patients with GSD, as highlighted in 1, 1, and 1.

From the FDA Drug Label

Pompe disease (acid maltase deficiency, glycogen storage disease type II, GSD II, glycogenosis type II) is an inherited disorder of glycogen metabolism caused by the absence or marked deficiency of the lysosomal enzyme GAA. Alglucosidase alfa provides an exogenous source of GAA Binding to mannose-6-phosphate receptors on the cell surface has been shown to occur via carbohydrate groups on the GAA molecule, after which it is internalized and transported into lysosomes, where it undergoes proteolytic cleavage that results in increased enzymatic activity. The recommended dosage is 20 mg/per kg body weight administered every 2 weeks as an intravenous infusion.

The management plan for glycogen storage disease involves the use of alglucosidase alfa (IV), which provides an exogenous source of the lysosomal enzyme GAA. The recommended dosage is 20 mg/kg administered every 2 weeks as an intravenous infusion. It is essential to monitor patients for potential hypersensitivity reactions, immune-mediated reactions, and cardiorespiratory failure. Patients should be managed by a clinical specialist knowledgeable in immune tolerance induction in Pompe disease 2.

From the Research

Management Plan for Glycogen Storage Disease

The management plan for glycogen storage disease (GSD) involves dietary modifications to prevent hypoglycemia and its biochemical consequences.

• The goal is to maintain blood glucose concentrations within a normal range to minimize biochemical abnormalities and optimize clinical outcome.
• Uncooked cornstarch (UCCS) is a key component of the treatment plan, as it helps to regulate blood glucose levels 3, 4, 5, 6.

Dietary Regimens

Different dietary regimens have been studied to determine the most effective way to manage GSD:

• A single dose of UCCS at bedtime can maintain plasma glucose concentrations above 3.9 mmol/L for at least 7 hours in most young adults with GSD-I 4.
• Divided doses of UCCS can also be effective, with one study showing that plasma glucose concentrations were maintained above 3.9 mmol/L for 9 hours in six out of seven subjects 4.
• A daytime schedule of six UCCS feedings, given with the three main meals and 180 minutes later, can maintain blood glucose concentrations at levels that minimize biochemical abnormalities and optimize clinical outcome 5.

Modified Uncooked Cornstarch

A new modified UCCS, Glycosade, has been developed to prolong euglycemia:

• A study found that Glycosade can maintain a longer fasting period and improve sleep quality in patients with GSD-Ia 6.
• The introduction of Glycosade was shown to improve sleep disturbances and maintain normal quality of life in patients with GSD-Ia 6.

Growth and Development

The effects of long-term use of dextrose and UCCS on physical growth and development have been compared:

• A study found that intermittent feedings of UCCS can provide an effective alternative to continuous overnight glucose for the treatment of GSD-I, with normal growth progression and maintenance of normal growth rate 7.
• However, growth failure that occurs before the onset of treatment may only be partially corrected, highlighting the importance of early intervention 7.