If muscle weakness increases in adulthood, a neurologist should be consulted to rule out myotonic dystrophy type 2. This is especially true if there are additional medical conditions such as cardiac arrhythmias or thyroid disease. Other synonyms for this disorder are: PROMM, DM2, and Ricker disease.
What is myotonic dystrophy type 2?
Myotonic dystrophy type 2 has a number of alternative names, but they refer to the same disease. In addition to the abbreviation DM2, the terms proximal myotonic myopathy (PROMM) or Ricker’s disease are used in the literature. It is a rare disease that has been known in Germany for about 12 years and was first described by Professor Kenneth Ricker. The disease is characterized by muscle weakness, which occurs with a delayed muscle relaxation of the thigh and hand muscles after a previous strain. The muscle weakness is slowly progressive and most pronounced in the pelvic girdle and shoulder region. Many patients experience pulling muscle pain, especially when climbing stairs or standing up. A number of other conditions may also occur in myotonic dystrophy type 2. These include cataracts and diseases of the heart muscle but also thyroid dysfunction as well as diabetes and impaired fertility.
Causes
The cause of myotonic dystrophy type 2 is a gene defect on the third chromosome. The sequences of the four bases here repeat more than in normal cases. Inheritance is autosomal dominant, whereby half of the children of an affected parent inherit the genetic defect, while the other half receive the healthy genetic makeup. The disease occurs between the ages of 16 and 50. Unlike type 1 of this disease, type 2 myotonic dystrophy also does not worsen from one generation to the next.
Symptoms, complaints, and signs
Myotonic dystrophy type 2 is characterized by symptoms similar to those of myotonic dystrophy type 1. The main feature is severely delayed muscle relaxation at older ages. This manifests itself in increasing [[Stiff joints (joint stiffness) and weakness of the musculature. Disturbed movements and muscle pain occur. In the course of the disease, cataracts also occur very frequently. The risk of developing diabetes mellitus is greatly increased. Cardiac arrhythmias are also very often observed. Since the testosterone level is too low, testicular atrophy may also occur. However, the ability to walk is usually only impaired at an older age. #
Overall, the course of myotonic dystrophy type 2 is much more benign than myotonic dystrophy type 1. Although it is a genetic disease, the first symptoms always begin in adulthood. There is no congenital form of the disease as in myotonic dystrophy type 1. Mental and physical developmental disorders do not occur. However, lens opacity and diabetes mellitus can often be diagnosed early. In contrast to myotonic dystrophy type 1, there is also no anticipation here. This means that when the disease is inherited, there is no advancement of symptoms to earlier years of life. However, instead of a cure of the disease, only an alleviation of the symptoms is possible.
Diagnosis and course
Diagnosis of myotonic dystrophy type 2 is difficult and therefore requires an experienced neurologist. After taking a history and performing a physical examination, an electromyogram (EMG) may provide initial evidence of the disease. If the first symptom is a cataract or a cardiac arrhythmia, the patient must be referred to a neurologist by the ophthalmologist or internist for further diagnosis. A targeted genetic test can confirm the diagnosis of myotonic dystrophy type 2 even before the onset of symptoms, especially if there is a corresponding family history. This is a blood test that is paid for by the health insurance. The course of the disease varies greatly. In general, the later the affected person experiences the first symptoms, the slower the progression of myotonic dystrophy type 2 can be expected.
Complications
As a result of this disease, affected individuals suffer from various symptoms that can make everyday life significantly more difficult.First and foremost, this results in severe muscle atrophy and pain in the muscles. This pain can also occur in the form of pain at rest and can lead to sleep problems at night and thus to depression or other psychological complaints. Furthermore, the patient’s ability to cope with stress decreases significantly and the eye lens becomes cloudy, possibly leading to cataracts. The patient’s everyday life is negatively affected by the visual complaints. Furthermore, the disease leads to heart problems, so that in the worst case the patient may die of cardiac death. The life expectancy of the affected person is thus significantly reduced by this disease. As a rule, there are no further complications during treatment. The discomfort of the eyes can be solved relatively well and easily, so that the affected person can see normally again. Further complaints are treated with the help of surgical interventions or through various therapies. In the process, no particular discomfort usually occurs either.
When should one go to the doctor?
A visit to the doctor should take place as soon as there is a weakening of muscle strength. Low physical performance or a decrease in the ability to bear weight are signs from the body of an existing disease. A doctor should be consulted as soon as the complaints persist over a longer period of time or increase in intensity. Pain in the muscles that is not due to short-term overuse or one-sided posture should be clarified by a doctor. If the affected person suffers from disturbances in mobility or if there are abnormalities in general movement patterns, a doctor is needed. If there are delays or peculiarities in the development of a growing adolescent, there is cause for concern. A visit to the doctor is necessary as soon as there are strong differences of the affected person in direct comparison with the possibilities of a peer. A reduction in the ability to walk, unsteadiness of gait, or an increased risk of falls and accidents should be discussed with a physician. Irregularities of the heart rhythm as well as impaired vision are further signs of an existing health disorder that must be examined and treated. If usual sporting activities can no longer be performed, consultation with a physician is necessary. If, in addition to the physical discrepancies, there is also mental stress, a visit to the doctor is also advisable. In case of behavioral abnormalities, mood swings as well as depressive tendencies, the affected person needs medical help.
Treatment and therapy
There is currently no direct drug therapy for myotonic dystrophy type 2. Therefore, treatment is based on the symptoms that occur and is intended to alleviate the impairments that do occur. This includes above all physiotherapy and other physiotherapeutic applications against the muscular complaints as well as medication to treat diabetes and possible thyroid disorders and cardiac arrhythmias. Most patients have little muscular impairment, since fine motor skills and also sensations in the limbs do not deteriorate in this disease. There are also no impairments in chewing and swallowing. Cataracts can be removed by surgery, which is usually performed on an outpatient basis. Local anesthesia is not a problem for the patient. However, in case of planned general anesthesia, it is essential to inform the anesthesiologist about the existing myotonic dystrophy type 2 in order to select the medication during anesthesia accordingly.
Outlook and prognosis
The prognosis for myotonic dystrophy type 2 is mixed. The main problem appears to be that the disease cannot be cured. The cause is a genetic defect. Doctors can only try to alleviate the symptoms that occur. In contrast, the disease does not appear until old age. The muscle weakness is usually less pronounced than in myotonic dystrophy type 1. Also, according to current knowledge, it is not accompanied by mental limitations. Fine motor skills are preserved. With appropriate therapy and physiotherapy, most signs can be abolished. Myotonic dystrophy type 2 can contribute to a shortened lifespan. Often a heart problem is the trigger for an early demise. The disease is very rare. One person out of 100,000 inhabitants suffers from it. There is usually an accumulation in families.Myotonic dystrophy type 2 is inherited. The probability of developing the disease as a senior citizen therefore increases if the muscle weakness was also present in other family members. The best chances of being free of symptoms for a long time result if myotonic dystrophy type 2 is treated at an early stage with appropriate therapies.
Prevention
Because myotonic dystrophy type 2 is a genetic disease, there are no direct preventive measures. However, if there is a relevant family history, genetic testing for this disorder should be considered, as it can be inherited. Possible symptoms of myotonic dystrophy type 2 can be detected and treated in a more targeted manner through a confirmed diagnosis. The patient can also cope better with the sometimes diffuse complaints due to the unambiguous diagnosis.
Follow-up
Follow-up care is not possible in myotonic dystrophy type 2. The disease is not treatable, and affected individuals can only enter inpatient treatment. During these inpatient stays, patients are taught how to maintain as much independence as possible despite their physical limitations. Both outpatient therapy and inpatient rehabilitation are adapted to the individual symptoms of the patients. Patients use physiotherapy and occupational therapy exercises to train their muscles in order to maintain their mobility for as long as possible. Speech therapists are on hand to help those affected improve their speech or even relearn it. Because in many cases the disease can also trigger psychological suffering such as depression, psychologists and social workers are available to help patients. The extent of the exercises depends on the physical and psychological condition. Precisely matching the right physical load is difficult. On the one hand, muscles and joints should be exercised. On the other hand, patients must not overexert themselves so as not to aggravate their symptoms. Inpatient stays usually last between four and six weeks. Afterwards, patients can receive regular physiotherapy or occupational therapy in their own environment. However, it is also possible to repeat the inpatient stay.
What you can do yourself
In the case of the disease, self-help is mainly aimed at improving the existing quality of life. This primarily includes maintaining mobility, independence and working capacity. Through physiotherapy, affected individuals can maintain or improve functions of individual muscles and strengthen the musculature in a targeted manner. In the case of swallowing or speech disorders, a speech therapist can relieve the symptoms and alleviate suffering through targeted exercises. In the case of problems with fine motor skills, occupational therapists help with targeted exercises to improve these again or to compensate for them with substitute movements. Since it is a genetic disease, it is important to inform the relatives about possible symptoms, who can exclude or diagnose the disease by means of a genetic test.
Some medications can lead to worsening of the disease. Therefore, it is helpful to carry a muscle emergency card with you. This can be obtained, for example, from the German Society for Muscle Diseases (Deutsche Gesellschaft für Muskelkranke e.V.). This can be actively shown to new doctors and passively helps in the event of accidents by providing the rescue service with all the necessary information and informing the attending doctors. Especially in case of general anesthesia, the anesthesiologist has to be considerate and tolerable therapeutics have to be used. Due to the progression of the disease, mood swings up to depression may occur, which can be treated within the framework of psychotherapy.
