Andersen’s disease is a particularly severe form of glycogen storage disease. It is an inherited disease characterized by the production of abnormal glycogen. The prognosis of the disease is very poor.
What is Andersen’s disease?
Andersen’s disease stores an unusual form of glycogen. This glycogen has a structure similar to amylopectin, which is present in a high percentage in vegetable starch. Normally glycogen is highly branched. In Andersen’s disease, however, only a weakly branched polysaccharide is present. See nonprofitdictionary for Iliotibial Band Syndrome (abbreviated as ITBS).
The disease is characterized by rapid enlargement of the liver, which quickly leads to liver cirrhosis. The abnormal polysaccharide can no longer be broken down and continues to accumulate. The deficiency or even the absence of the enzyme amylo-1,4-1,6-transglucosidase is responsible for the faulty glycogen formation. It provides the branching in this polysaccharide molecule.
The disease is very rare, but still occurs in different manifestations or forms. In the extremely severe form, the child is often stillborn. Milder forms that start at a later age have also been described. In any case, however, there is a mutation in the gene (GBE1), which is located on chromosome 3.
Causes
The cause of Andersen’s disease is a genetic defect in gene GBE1 on chromosome 3, which is inherited in an autosomal recessive manner. This gene is responsible for the synthesis of the enzyme amylo-1,4-1,6-transglucosidase. If this enzyme is missing or only works to a limited extent, normal glycogen can no longer be synthesized. The enzyme is responsible for the branching of the polysaccharose molecule.
If this branching does not occur or is only carried out incompletely, a glycogen is formed which can no longer be broken down to supply energy quickly. On the contrary, it accumulates very quickly in the liver, spleen and lymph nodes. After each meal, some of the unused glucose is transported to the liver to be stored as glycogen.
However, this reserve substance cannot be used in its present form. The continued storage of the abnormal glycogen increases the size of the liver and spleen, leading to the inevitable destruction of both organs.
Symptoms, Ailments & Signs
Andersen’s disease is characterized by an extraordinary variability. It is about the constant storage of an abnormal glycogen, which can no longer be broken down. But the manifestation of the disease can be different. Nevertheless, the overall prognosis for Andersen’s disease is very poor. The prominent symptom is a constantly enlarging liver, from which liver cirrhosis quickly develops.
The most severe form is already evident in the absence or reduced movement of the child before birth. The fetus shows signs of joint stiffness and pulmonary hypoplasia. In these cases, the child is usually stillborn. In the classic cases, the child is still developing normally at birth. However, during the first months of life, hepatomegaly (enlarged liver) and hypotonia (lack of muscle tone) develop.
Overall, the development of the child is delayed. The disease progresses quickly. The liver develops cirrhosis. There is also increased portal vein pressure and the spleen enlarges. Due to cirrhosis of the liver, varices develop in the esophagus with associated bleeding and ascites. Death usually occurs in early childhood. In rarer cases, the disease has a later onset and shows symptoms of muscle weakness and heart failure. Neurological symptoms also appear here.
Diagnosis & course of disease
The diagnosis can be made on the basis of the clinical picture and accompanied by laboratory tests, liver biopsies and molecular genetic tests. The intracellular accumulation of stainable amylopectin-like structures is noticeable in the histological examinations. The responsible enzyme is examined in the hepatocytes, fibroblasts and leukocytes. A detected lack of amylo-1,4-1,6-transglucosidase confirms the diagnosis.
Complications
As a rule, the life expectancy of the child is significantly reduced by Andersen’s disease or the child is born dead. This can lead to severe psychological problems or depression, especially among relatives or parents. In most cases, these are then dependent on psychological treatment.
Affected children suffer from liver cirrhosis, which eventually leads to death. Furthermore, the joints are stiff and movements are no longer possible due to this complaint. The mental development of the child is also severely impaired by Andersen’s disease, so that those affected are usually always dependent on the help of other people. It is not uncommon for heart failure or muscle weakness to occur.
Patients can also die from cardiac death. Unfortunately, Andersen’s disease cannot be cured. Even a liver transplant can only alleviate the symptoms for a short time, since the damage to the new liver will also occur. This eventually leads to the death of the child. Until then, however, the complaints and symptoms can be limited with the help of medical measures.
When should you go to the doctor?
Andersen’s disease is a genetic disease that, in severe cases, can result in death of the fetus in the womb. Therefore, pregnant women should seek medical treatment as soon as any irregularities or abnormalities are noticed during pregnancy. If the mother-to-be has a vague feeling that something might be wrong with the unborn child, she should see a doctor. If the newborn survives the first few days and weeks after delivery, a doctor is needed as soon as there are any special features in the further course of development. A doctor should be consulted if there is muscle weakness or movement disorders.
Growth disorders are signs of an existing disease and must be clarified. Abnormal heart activity, deformations of the body and discrepancies in child behavior must be examined and treated. In many cases, the disease leads to an enlargement of the organs. The liver or spleen are particularly affected in these cases.
Therefore, a doctor is needed as soon as there is an unusual shape of the upper body compared to infants or children of the same age. A discoloration of the skin or other irregularities in the complexion are further signs of a health impairment. Yellowing of the face or eyes should be evaluated by a doctor.
Treatment & Therapy
Since the disease is genetic, no causal treatment can be given. Therapy is only symptomatic. As part of the treatment, doctors focus mainly on complications that arise. This reduces the pressure in the portal vein circulation. Furthermore, there is a substitution of albumin and coagulation factors.
In liver failure, a liver transplant can prolong life. However, the disease cannot be cured even with a liver transplant. The genetic defect is present and will also lead to deposits of the abnormal glycogen in the new liver. The storage of the faulty polysaccharide also continues in the other organs of the so-called reticulohistiocytic system of the spleen and lymph nodes, so that serious complications can still occur even after a successful liver transplant.
The reticulohistiocytic system is part of the immune system and includes the cells of the reticular connective tissue. These cells store particles and substances in order to break them down and then transport them out of the body. However, the breakdown of the defective polysaccharose molecules is no longer possible here either.
Outlook & Forecast
Andersen’s disease has a relatively poor prognosis. The metabolic disease has not yet been cured and causes severe liver damage. In some cases, muscle problems and concomitant diseases occur, which progress progressively if left untreated. Life expectancy is significantly reduced by the condition. On average, sick children reach the age of two to five years. Early liver transplantation improves the prognosis. The prognosis is particularly bad for the classic forms of the disease, especially if no liver transplant is performed in the first few months of life.
As a rule, the long-term prognosis is based on the extent, severity and progression of the disease. Andersen’s disease is one of the most severe glycogen diseases. Due to the liver problems and other symptoms, the quality of life is usually greatly reduced. Pain medication and comprehensive therapy improve the well-being of the child, but are also associated with risks. The responsible liver specialist makes the prognosis.
Life expectancy is significantly reduced by the condition. Any comorbidities that can occur with undetected diseases are also included in the prognosis. Overall, Andersen’s disease has a poor prognosis. Novel treatment methods could bring an improvement in the future.
Prevention
Prevention of Andersen’s disease can only refer to the fact that the offspring does not inherit this disease. Since Andersen’s disease is passed on in an autosomal recessive manner, several generations can be skipped during inheritance. If cases of Andersen’s disease have already occurred in the family and relatives, human genetic tests should therefore be carried out.
If the gene is found in both parents, human genetic counseling is recommended. In this case, there is a 25 percent probability of the offspring developing Andersen’s disease.
Aftercare
Since Andersen’s disease cannot be cured, the treatment of the symptoms and the containment of possible complications are the main focus throughout the treatment period. However, follow-up care is necessary after interventions that are carried out as part of the therapy. If there is a liver transplant, professional follow-up care is very important.
After the procedure, this ensures that the new liver is not rejected by the body. Special drugs dampen the body’s immune response. As a result, however, the body’s defenses against pathogens are also weakened, which must be taken into account in further therapy. During this time, the patient must undergo regular blood tests. Care is taken to ensure that there are neither rejection reactions nor other serious complications such as kidney dysfunction, which can occur as a side effect.
While the core symptoms of Andersen’s disease can be improved immediately following liver transplantation, the accumulation of defective glycogen continues to occur, so that complications and progressive symptoms must be expected even after transplantation. The responsible liver specialist can give more detailed information about the prognosis and the further course of the treatment.
You can do that yourself
The self-help measures that a patient with Andersen’s disease can take are limited to non-existent. Since the disease has genetic causes and cannot be controlled despite symptomatic treatment, the options for those affected are quickly exhausted. He is best advised to take any dietary and lifestyle advice from his treating physician seriously and to implement it.
Furthermore, after a liver transplant, the person concerned should think about careful behavior. Alcohol, fatty foods and exertion should be avoided. This makes it easier for the body to really accept the new organ. However, a successful transplantation including successful aftercare cannot stop type 4 glycogenosis itself.
Since the disease is inherited in an autosomal recessive manner (it can skip several generations), it makes sense to have a genetic profile created with regard to family planning. While those affected by Andersen’s disease know about their gene anyway, an analysis in this regard is particularly worthwhile for family members. In this way, the transmission of the triggering gene can be prevented by appropriate family planning. At least, however, certainty can be obtained about the risk of disease in one’s own offspring.
