The signs and symptoms of late-onset Pompe disease (LOPD) differ from person to person and may become evident at any age from older than 1 year of age to late adulthood.
These sample patient experiences illustrate how the disease can affect people differently and variable the symptoms can be:
A 40-year-old woman experiences progressive facial and left-sided numbness followed by general achiness
A 36-year-old man starts falling asleep during the day and has trouble breathing when he is lying down
A 17-year-old girl has muscle weakness and trouble breathing that worsens, eventually requiring occasional respiratory support
A 72-year-old man notices increasing muscle weakness and breathing problems
No matter the symptoms, the cause of Pompe disease is the same: reduced or absent levels of a protein (acid alpha-glucosidase, or GAA enzyme) that results in the buildup of excess glycogen within the lysosomes of many cells but affects mainly muscle cells. This buildup of glycogen results in progressive muscle weakness which can affect many different parts of the body and cause a variety of health problems. In some cases, the initial impact may be very serious and progress (worsen) rapidly, while in others it may be less extreme and progress more gradually. Below you will find a list of some symptoms that are common in most people with LOPD, and a brief description of how the disease progresses. For a more comprehensive list of signs and symptoms of LOPD, click here.
Some broad generalizations can be made with respect to the signs and symptoms of LOPD. Most people experience muscle weakness in the arms and legs, usually most prominently in the legs, making walking or climbing stairs difficult. Pompe also affects muscles used for breathing, making it difficult to breathe, especially when lying down. Table 1 lists some other symptoms that patients with LOPD may experience in order of the frequency by which they usually appear.
Table 1.Common Symptoms Of LOPD, In Descending Order Of Frequency
|Respiratory Weakness in the Muscles that Help with Breathing||
Table 1.Common Symptoms Of LOPD, In Decreasing Order Of Frequency
Respiratory Weakness in the Muscles that Help with Breathing
Patients with LOPD have a slower progression of symptoms than patients with the infantile-onset form of the disease, but the disease is always progressive, meaning that its symptoms worsen over time. In general, the earlier in life the symptoms appear, the faster the rate of progression.
The rate of disease progression can sometimes be unpredictable. In addition, an abrupt and rapid decline can happen at any time, so careful monitoring of the disease’s progression is very important.1 Whether the disease progresses fast or slowly, movement and breathing difficulties will eventually worsen over time.