Duchenne Facts
Heart
Cardiomyopathy: Almost all patients with DMD develop dilated cardiomyopathy, which impairs the heart's pumping function. The heart enlarges and the walls of the heart muscle become thinner and weaker.
Cardiac arrhythmias: In addition to the reduced pumping capacity, many sufferers also experience cardiac arrhythmias.
Symptoms: Symptoms such as shortness of breath, fatigue, dizziness or heart palpitations often only appear later on. In the early stages of the disease, cardiac involvement may be asymptomatic.
lung
Weakening of the respiratory muscles: DMD causes a progressive loss of muscle strength, including the diaphragm muscles and the muscles surrounding the ribs. These muscles are crucial for breathing, and their weakening leads to reduced respiratory efficiency.
As the disease progresses, patients must be ventilated 24/7. Many sufferers are ventilated using nasal masks and some are ventilated using a tracheotomy.
Reduced lung function: Weakened respiratory muscles impair the ability to fully fill the lungs and exhale air. This leads to reduced vital capacity (lung volume), which often begins in the teenage years and worsens as the disease progresses.
Respiratory infections: Due to the limited ability to breathe effectively and clear mucus from the airways, people with DMD are more susceptible to respiratory infections such as pneumonia.
Weakened cough reflex: A weakened cough reflex increases the risk of secretions remaining in the lungs, which in turn promotes infections. An electric cough aid makes it easier or possible for those affected to cough up.
Kidneys
Drug treatment: Patients with DMD often receive long-term drug treatments, such as corticosteroids (such as prednisone or deflazacort) to slow muscle degeneration. Long-term use of these drugs can in some cases cause kidney problems, such as impaired kidney function or an increased tendency to form kidney stones.
Heart and lung failure: The heart and lung complications caused by DMD can indirectly put a strain on the kidneys later in the disease. Severe heart failure or breathing problems can lead to reduced blood flow to the kidneys, which can lead to impaired kidney function in the long term.
Dehydration and infections: Patients with DMD, especially those on a ventilator later in the disease course, may be more susceptible to dehydration, which can increase the risk of kidney complications. Infections, which may occur more frequently when the immune system is weakened, also have the potential to affect the kidneys.
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Renal function in advanced DMD stages:
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In advanced stages of DMD, when cardiac or respiratory failure predominates, the kidneys may be affected due to poor blood supply or due to multiorgan failure.
Blood pressure management: Because many patients take medications to treat heart problems that also affect blood pressure (such as ACE inhibitors or diuretics), the kidneys need to be monitored regularly to make sure these medications are not having harmful effects on the kidneys.
Colon
Constipation:
One of the most common gastrointestinal complaints in DMD patients is constipation, which is caused by a combination of limited movement (immobility), low abdominal muscle strength and slower intestinal motility.
Muscle weakness also affects the smooth muscles of the intestine, resulting in delayed bowel movement. This can cause the digestive process to slow down, causing symptoms such as bloating, abdominal pain and a feeling of fullness.
Difficulty in defecation:
Patients in advanced stages of DMD may also have difficulty controlling bowel movements without assistance or completely emptying the bowel because the abdominal muscles are severely weakened.
Swallowing disorders (dysphagia):
Some people with DMD develop difficulty swallowing later in life because the muscles in the upper digestive tract, including the muscles of the throat and esophagus, can also be affected. This can make it difficult to eat and increase the risk of aspiration pneumonia (pneumonia caused by inhaling food or liquids).
Gastrointestinal reflux (GERD):
Some patients with DMD experience gastroesophageal reflux (GERD), in which stomach acid flows back into the esophagus. This can be exacerbated by weakness of the muscles in the lower esophageal sphincter (the muscle that separates the stomach from the esophagus).
Brain
Learning difficulties:
About one-third of boys with DMD have mild cognitive impairments. These may include delayed language development, learning difficulties, or problems with working memory and processing speed.
Language skills and executive functions, such as the ability to plan, solve problems and regulate oneself, are often particularly affected.
Attention Deficit and Hyperactivity (ADHD):
Some children with DMD exhibit symptoms of ADHD, including inattention, hyperactivity, and impulsivity. This can affect academic success and social behavior.
Autism spectrum disorders (ASD):
There is evidence that boys with DMD are more likely to exhibit features on the autism spectrum, including difficulties in social interaction, limited communication, and repetitive behavior patterns.
Intelligence level:
Although the majority of boys with DMD have normal intelligence, the average IQ tends to be somewhat lower than in the general population. However, more severe intellectual disabilities are rare.
Emotional and behavioral problems:
Boys with DMD may also experience emotional problems such as anxiety and depression, especially as they get older and their physical abilities decline. These emotional challenges are often due to the social and physical limitations that the disease imposes, but may also be related to the neural changes in the brain.
Epilepsy:
Some boys with DMD may experience seizures, although epilepsy in general is not common in DMD. When seizures do occur, they are often mild and easily treatable.
Tendons
Especially when eating and drinking, those affected may cough or choke more frequently because food or liquids enter the respiratory tract.
Longer meal times: Because the swallowing process becomes slower and less efficient, eating and drinking takes longer than usual.
Nutritional problems and weight loss: Difficulty swallowing can reduce food intake, leading to inadequate nutrition and weight loss.
Aspiration pneumonia: A serious risk is inhaling food or liquid into the lungs, which can lead to pneumonia (aspiration pneumonia).
In most cases, those affected are fed artificially during the course of the disease using a gastric tube (PEG), which leads through the abdominal wall directly into the stomach.
Nahrungsaufnahme
Achilles tendons: Shortening of the Achilles tendons leads to a condition called equinus, where the foot is pulled into a straight position. This can make walking difficult and often leads to patients walking on their tiptoes before they lose their ability to walk completely.
Knee and hip joints: These joints can also remain in a bent position due to shortened tendons, which makes sitting and standing difficult.
Elbows and wrists: Tendon shortening can also occur in the upper extremities, which limits the mobility of the arms and hands.
Stiffness and loss of mobility:
When the tendons and muscles shorten, the affected joints increasingly lose their mobility. This not only leads to pain and discomfort, but also limits the patient's independence.
Uneven muscle strain:
Because certain muscles are weaker than others, there is an uneven load on the tendons, which exacerbates the shortening and can lead to misalignment of the joints.