Brancher deficiency refers to a medical condition characterized by the absence or malfunctioning of the enzyme called lysosomal acid alpha-glucosidase (GAA) within the lysosomes of cells. This enzyme is responsible for breaking down glycogen, a complex sugar molecule, into glucose, which can be used as an energy source in various bodily tissues. In the absence or deficiency of GAA, glycogen accumulates within the lysosomes, leading to the impaired function of different organs and tissues.
Brancher deficiency, also known as glycogen storage disease type IV (GSD IV), is an inherited genetic disorder caused by mutations in the GAA gene. It can present in two forms: a more common infantile form, which manifests shortly after birth, or a rarer late-onset form, which may present in adolescence or adulthood. Symptoms can vary widely in severity, but commonly include muscle weakness, low muscle tone, enlarged liver, respiratory issues, and heart problems.
The diagnosis of brancher deficiency often involves a combination of clinical evaluations, genetic testing, and enzyme activity assays. Treatment mainly focuses on managing symptoms and preventing complications. This can involve dietary modifications, such as a low-sugar and high-protein diet, as well as physical and occupational therapy to address muscle weakness and develop motor skills.
In summary, brancher deficiency is a genetic disorder characterized by deficient or dysfunctional GAA enzyme, leading to abnormal glycogen accumulation and subsequent organ dysfunction.
