Glycogen storage disease type 4
- GSD 4
- Andersen disease
- Brancher deficiency
- Glycogen branching enzyme deficiency
There have also been reports of neuromuscular forms of GSD 4, most of which become apparent in late childhood. These may be characterized by skeletal muscle or heart muscle disease (myopathy or cardiomyopathy) caused by the accumulation of glycogen in the muscle tissue. Signs and symptoms in these cases may include muscle weakness or fatigue, exercise intolerance, and muscle wasting (atrophy). Complications with these forms may include heart failure.
A more severe neuromuscular form that is apparent at birth has also been reported; this form may be characterized by generalized edema (swelling cause by fluid); decreased muscle tone (hypotonia); muscle weakness and wasting; joints having fixed positions (contractures); and neurologic involvement, which can cause life-threatening complications early in life.
The Human Phenotype Ontology provides the following list of signs and symptoms for Glycogen storage disease type 4. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms.
The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature.
The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined.
Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
- Marsden D. Andersen Disease (GSD IV). NORD. 2012; http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/394/viewAbstract. Accessed 12/23/2012.