Pompe’s Disease

Abstract

Pompe disease is also known as Glycogen storage disease type II or GAA deficiency or Acid alpha-glucosidase deficiency. It is a disorder that damages the nerves cells and muscles throughout the body.  It is an autosomal recessive metabolic disorder that is as a result of glycogen accumulation in the lysosome which causes lysosomal acid alpha-glucosidase enzyme deficiency. The enzymes that are affected usually catalyze the reactions which convert glycogen compounds into monosaccharides and in this case the glucose is the predominant component. When this happens there is glycogen accumulation in tissues and mainly in the muscles which impair their ability to function as they are intended to. The main organs that the disease affects are the muscles, liver, and heart. The disease is mostly inherited from the parents but the symptoms can start at birth or when one is even more than 60 years.

Introduction

Pompe disease is a disorder that is inherited from parents. A person can start having the symptoms either at early ages or at late adulthood. The disease is named after Joannes Cassianus Pompe and it is because he is the one who characterized it in the year 1932. Previously the disease was a just unknown disorder but Pompe described it as the accumulation of glycogen in the muscles. Nevertheless, the disease remained just a mystery until 1955 when Christian de Duve’s discovered the lysosomes. It was in 1965 when Henri G. Hers who was a co-worker of Christian realized that lysosomal enzyme deficiency which breaks down the glycogen could be used to know the symptoms of Pompe disease. The paper will focus on what causes Pompe disease, what has been altered or damaged in this disorder and the age and race that are affected. It will further look at the symptoms, treatment options, and the prognosis.

Pompe disease is caused by inheriting it from the parents. The child inherits from both parents where he or she inherits two flawed genes one from each parent. According to U.S. Department of Health & Human Services (2018), the disease is as a result of lack of enough acid alpha-glucosidase which helps to break down glycogen. Since glycogen is not broken down as it is supposed to be then it builds up in the body cells. When this occurs for sometimes then it damages the muscles and it will depend on where the damage has occurred for instance if it is on the legs then walking will not be usual and if it is on the lungs then breathing will be difficult (Chien, Hwu & Lee, 2013). The parents may be a carrier in that they have the disease yet they are not affected by the symptoms. Statistics show that there is 50% chance that when parents are carriers they can get a baby who is a carrier too and 25% to have a child who is not affected nor a carrier. Obligate carriers are the parents who have a child with Pompeo disease (Emory University School of Medicine, 2017).

According to Emory University School of Medicine (2017), in every 40,000 individuals, one person has Pompe disease. Nevertheless, this rate varies with ethnicity. On these 1 in 40,000 individuals, the chance of a person to have the disease without the family history is 1 in 10. Pompe disease affects every race but it is more common in some races (Emory University School of Medicine, 2017). For instance, in the Caucasian population, 1 in 100,000 individuals has the infantile-onset Pompe disease and 1 in every 60,000 individuals has the late-onset Pompe disease. On the other hand, in African-American population 1 in 14, 000 individuals has the disease (Emory University School of Medicine, 2017). Furthermore, cases of infantile-onset Pompe disease are more in Taiwan and China than other countries.

According to (Chien, Hwu & Lee, 2013), the symptoms are different for different people and they vary if one suffered the disease at an early age or at adulthood. For babies between a few months old and an age of one year, the disease is referred as early-onset Pompe disease. The symptoms include trouble when eating and lack of weight gain, poor neck and head control, enlarged liver, delays in rolling over as well as sitting up, enlarged tongue, hearts defects and breathing problems which are caused by lungs infections.  The symptoms can start at an older age as late as at the age of 60 years and is mostly referred to as late-onset Pompe disease (Chien, Hwu & Lee, 2013). The symptoms include stiff joints, a spinal curve, and weakness in the trunk, legs, and arms, breathing problems while sleeping and enlarge liver. Other symptoms are chewing and swallowing problems due to the enlarged tongue, lung infections, shortness in breath, as well as hard time while exercising (ACMG Work Group on Management of Pompe Disease, 2016).

Currently, there is no cure for Pompe disease. Nevertheless, FDA has approved a treatment called Myozyme which is basically an enzyme replacement therapy that is produced by Genzyme Therapeutics (Chien, Hwu & Lee, 2013). The therapy replaces the missing enzymes in the patient’s body by way of lifetime IV infusions of Myozyme (U.S. Department of Health & Human Services, 2018). Nevertheless, the therapy can improve the condition of some patients whereas others cannot improve. The major improvements that the therapy does include the decrease of the heart size, normal heart functioning, improvement in tone, strength, muscle functioning, as well as reduction of glycogen accumulation. In addition, supportive care is one of the most imperative treatments for Pompe disease since the patient requires being helped when breathing, walking among others. Other treatment researches that are been conducted include the chaperone therapy which will make enzyme replacement more effective.

If a baby is not treated with enzyme replacement therapy then he or she will die of cardiac failure or respiratory infection before the age of one or 2 years (Emory University School of Medicine, 2017). On the other hand, for the late-onset individuals, it depends on the age of the onset, the later the age of the symptoms on late-onset, the slower the progression of the disease. When one is treated with enzyme replacement therapy be it a baby or an adult, then he or she can stay a normal life with no threatening symptoms. Nevertheless, in all the cases, the respiratory muscle involvement will determine the prognosis (Emory University School of Medicine, 2017). Some of the risk factors that can cause the disease to be more serious is air regulation, this is mostly in cases where the disease has affected the respiratory system and the patient is kept in a room where there is air pollution or no sufficient air. Other risk factors include smoking, alcohol among others.

In conclusion, Pompe disease is a rare condition but it affects people of all ages and gender. The disease is passed through from the parents to the kinds. It has numerous symptoms but the major one is muscle weakness which when left untreated it gets worse and can result in death. The main cause for this disease is the accumulation of glycogen in the lysosome which causes lysosomal acid alpha-glucosidase enzyme deficiency. Nevertheless, the disease has no cure but it can be controlled through enzyme replacement therapy. When detected early the patient has a chance of resuming his or her normal working activity but if left for a long time the patient risks permanent negative health effects.