What is Hers disease?
Hers disease (or Hers disease , glycogenosis type VI ) is a genetic metabolic disorder caused by a deficiency of the enzyme, liver phosphorylase. This enzyme is necessary for the breakdown (metabolism) of glycogen, a carbohydrate that is stored in the liver and muscles and used for energy production. Deficiency of this enzyme leads to abnormal accumulation of glycogen in the body. Hers disease belongs to a group of disorders known as glycogen storage diseases. Hers disease is characterized by an enlarged liver (hepatomegaly), moderately low blood sugar (hypoglycemia), elevated levels of acetone and other ketone bodies in the blood (ketosis), and mild growth retardation. Symptoms are not always obvious during childhood, and children are usually able to lead normal lives.
Treatment and patient care
Therapy for Alzheimer's disease includes a set of measures, including drug treatment, psychosocial correction, and patient care.
There are no medications that can cure the disease. To treat cognitive impairment, doctors prescribe chemicals from the group of inhibitors that can delay the course of physiological processes in the body, as well as NMDA receptor antagonists, designed to reduce the manifestation of negative symptoms.
Behavioral correction involves the use of art therapy, music therapy, communication with animals and stimulation of any type of activity in the patient. The goal is to improve the patient’s quality of life.
No care is required at first. We are talking only about help in performing certain functions, possible tips. Relatives cope with this successfully. But in the last stages of Alzheimer's disease, the patient requires complete care. If relatives do not have the opportunity to constantly be with the patient, a nurse is hired for these purposes. Many people choose help from specialized institutions.
A good example is the private boarding house “Idyll” in Yekaterinburg. The cost of the stay is comparable to the pension of many patients. The institution employs doctors and medical staff who are well acquainted with the specifics of diseases such as Alzheimer's disease. Elderly people are provided with 24-hour care. Restorative and cultural events are being carried out.
Signs and symptoms
Although symptoms of Hers disease may not appear during childhood, some enlargement of the liver will be observed. Many patients will have no obvious symptoms. In general, low or moderately low blood sugar (hypoglycemia) may be present, which can cause symptoms of weakness, fatigue, hunger and nervousness. In some cases, there is a decrease in muscle tone (muscle hypotonia) and mild muscle weakness.
Affected children may grow slowly and the liver will become enlarged due to excess glycogen accumulation. Glycogen is a stored form of energy obtained from carbohydrates. In many cases, the body can adapt to low blood sugar levels and can produce energy in other ways. Therefore, symptoms may go undetected for long periods of time.
Liver enlargement often disappears during puberty, and final height in adults is often normal. Also, muscle strength and tone usually return by adulthood.
Symptoms of Alzheimer's disease
Neither patients nor their loved ones can say exactly when the changes began. The person becomes forgetful and cannot remember individual words. The mood often changes, tearfulness and touchiness occur. Possible sleep disturbances. Poor night sleep gives way to daytime sleepiness.
The first symptoms of Alzheimer's over time are complemented by other manifestations:
- the circle of interests narrows, life becomes monotonous;
- lack of composure, confusion, suspiciousness, and uncertainty are manifested in everything;
- professional skills are lost;
- It becomes more and more difficult to perform everyday tasks;
- a person gets lost in the area, disoriented in space;
- degradation of thought processes occurs.
Visual dysfunction is added to acquired dementia. In the final stages, the sick person does not recognize loved ones, cannot eat, dress, or take care of himself.
Causes
Hers disease is inherited in an autosomal recessive manner. The disorder is caused by a deficiency of an enzyme known as liver phosphorylase. Because of this enzyme deficiency, a stored form of energy derived from carbohydrates (glycogen) can accumulate in the liver.
Genetic diseases are determined by two genes, one from the father and the other from the mother. Recessive genetic disorders occur when a person inherits the same abnormal gene for one trait from each parent. If a person receives one normal gene and one disease gene, the person will be a carrier of the disease, but usually asymptomatic. The risk of two carrier parents both passing on the abnormal gene and therefore infecting the child is 25% in each pregnancy. The risk of having a child who will be a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%.
Researchers have determined that Hers disease occurs as a result of a disruption or change (mutation) in the liver glycogen phosphorylase gene (PYGL gene, located on the long arm (q) of chromosome 14 (14q21-q22). The PYGL gene encodes the liver phosphorylase enzyme. Chromosomes that are present in the nucleus human cells, carry the genetic information of each person. Pairs of human chromosomes are numbered 1 to 22 with an additional 23rd pair of sex chromosomes, which include one X and one Y chromosome in males and two X chromosomes in females. Each chromosome has a short arm, labeled "p", and the long arm labeled "q". Chromosomes are further subdivided into many numbered bands. For example, "chromosome 14q21-q22" refers to bands 21-22 on the long arm of chromosome 14. The numbered bands indicate the location of the thousands of genes present on every chromosome.
Classification of the disease
Throughout the disease, a pattern of progressive disorders is observed. According to symptoms, there are four stages of Alzheimer's: predementia, early, moderate and severe. Slow degradation occurs over an average of 7 years, ending in the death of the patient.
Initial stage (pre-dementia)
The first manifestations of Alzheimer's disease, such as memory impairment and lack of concentration, are mistakenly perceived by relatives as manifestations of aging. Problems with the performance of everyday functions are still barely noticeable. It is typical that already at this time the person becomes apathetic, which persists throughout the disease.
Early stage
Memory continues to decline. The patient retains clear consciousness and high sensitivity, but the ability to normally perceive information is lost. For example, a person does not recognize or partially recognizes familiar faces. Or he cannot determine which objects in his environment have the same color. Clumsiness in performing daily tasks appears, fine motor skills are impaired. With some manipulations, the patient requires help, although he can still do many things on his own.
Moderate stage
The condition is worsening, as evidenced by obvious speech impairments. To replace a forgotten word, a person often selects the wrong words. Consistent movements are difficult. Most everyday tasks require significant effort. Psychiatric deviations appear, for example, the idea of vagrancy. Irritability can come and go quickly. Symptoms of delirium often occur. The person becomes whiny. It happens that he resists help. In order to smooth out the increase in general stress, relatives often move the sick person to a hospital for care.
Severe stage
At this stage, the patient cannot live without outside help. He is able to pronounce individual words and phrases, understands other people's speech and can show emotions. The condition is characterized as apathetic, exhausted. In the end, even small actions are impossible without the participation of others.
Based on its form, Alzheimer's disease is divided into presenile and senile. The first is a disease detected before age 65. The senile form refers to patients older than this age. Presenile dementia is characterized by rapid progression, family history, and rapid impairment of speech functions. The pace of progress depends on the standard of living, type of activity, heredity, and the presence of chronic diseases.
Senile dementia develops slowly at first. The first stages last 2-4 years. Temporary improvements in condition are characteristic. An elderly patient remembers the past perfectly, but does not perceive new knowledge. As it progresses, false memories arise, and people from the current environment are associated with people from their youth. There is no complete breakdown of speech. On the contrary, a sick person can speak vividly to the end and retain a rich vocabulary.
Disorders with similar symptoms
Symptoms of the following disorders may be similar to those of Hers disease. Comparisons can be useful for differential diagnosis:
- Gierke's disease (von Gierke's glycogenosis, glycogenosis type I) is characterized by the accumulation of glycogen and fat in the liver and kidneys, which can lead to liver and kidney enlargement and growth retardation leading to short stature. Glycogenosis type I is associated with abnormalities in the G6PC gene or the SLC37A4 gene, which lead to enzyme deficiencies that cause excess glycogen in body tissues and low blood glucose levels. Glycogenosis type I is inherited as an autosomal recessive genetic disease.
- Forbes disease (glycogenosis type III) is characterized by excess amounts of abnormal glycogen (a stored form of energy that comes from carbohydrates) in the liver, muscles and, in some cases, the heart. Symptoms are caused by a deficiency of the enzyme amylo-1-6-glucosidase and include growth retardation, low blood sugar (hypoglycemia), increased levels of fatty substances in the blood (hyperlipemia), bloating and an enlarged liver. Forbes disease is inherited in an autosomal recessive manner.
- Hereditary fructose intolerance is an inherited inability to digest fructose (fruit sugar) or its precursors (sugar, sorbitol and brown sugar). The disease is associated with a deficiency in the activity of the enzyme fructose-1-phosphate aldolase, which leads to the accumulation of fructose-1-phosphate in the liver, kidneys and small intestine. Fructose is a naturally occurring sugar that is used as a sweetener in many foods, including many baby foods. This disorder can be life-threatening in infants and ranges from mild to severe in older children and adults. People who have hereditary fructose intolerance usually have a strong aversion to sweets and fruits. After eating foods containing fructose, they may experience symptoms such as severe abdominal pain, vomiting, and low blood sugar (hypoglycemia). Hereditary fructose intolerance is inherited in an autosomal recessive manner.
Standard Treatments
Because the symptoms of Hers disease are usually mild, the disorder usually does not require treatment other than avoiding prolonged fasting and monitoring by a doctor. People experiencing hypoglycemia during fasting may be advised to eat foods high in carbohydrates frequently.
Genetic counseling may also be helpful for affected individuals and their families. Other treatment is symptomatic and supportive.
Forecast
People with Hers disease have an excellent prognosis for normal growth and development, even without diet during childhood. Most patients experience resolution of hepatomegaly, hypotension, muscle weakness, risk of fasting hypoglycemia, and abnormal biochemical parameters before or during puberty. The overall prognosis of rare variants of the disease involving muscle or heart failure depends on the degree of organ dysfunction.
