Werdnig Hoffmann disease is a form of spinal muscular atrophy. This condition impacts nerves that control voluntary movement in the body. There is currently no cure for it. But physical therapy and other treatments can help manage symptoms.
This article will explain Werdnig Hoffmann disease, its symptoms, causes, and risk factors.
It will also cover diagnosis and treatment for people living with the disease.
Finally, we consider the outlook for a person with this condition.
Werdnig Hoffmann disease is a type of spinal muscular atrophy also known as spinal muscular atrophy type 1 (SMA-1).
SMA-1 is a neuromuscular condition that damages and kills motor neurons, which are nerve cells that control certain voluntary movements in the body. These include muscles in the face, throat, legs, and tongue.
Individuals with Werdnig Hoffmann disease typically receive a diagnosis before
Werdnig Hoffmann disease makes up about
Symptoms of Werdnig Hoffmann disease can vary between infants. Some common symptoms
- difficulty swallowing and breathing
- decreased muscle tone
- absence of certain tendon reflexes
- joint hypermobility
- tongue twitches or spasms
- lack of head control
- inability to walk, stand, or sit
- difficulty controlling muscles
Most infants with Werdnig Hoffmann disease are very weak at birth. The muscles in their limbs are typically underdeveloped.
Only half of babies with this condition will survive until birth. For those that survive, as they grow, the disease continues to progress. More motor neurons become damaged over time, leading to worsened symptoms.
People with Werdnig Hoffmann disease have a damaged copy of a certain gene. This is the SMN1 gene, which plays an important part in motor neuron function. Damage to this gene causes the symptoms of Werdnig Hoffmann disease.
Researchers believe that another gene, SMN2, affects the severity of this condition. Damage to this gene can lead to more severe cases of Werdnig Hoffmann disease.
The disease impacts around
People with a family history of spinal muscular atrophy have a higher risk of passing this condition on to their children. These people may pursue genetic testing before having a child. A blood test can determine whether a person is a carrier of spinal muscular atrophy.
If both parents are carriers, the risk of having a child with spinal muscular atrophy is 1 in 4. Parents may pursue in vitro fertilization (IVF) or sperm donation to reduce the chance of their child having this condition.
Infants with symptoms of Werdnig Hoffmann disease should receive a full evaluation from a medical professional. A doctor can perform a physical exam to see if the child has physical signs of the condition.
A person with a family history of Werdnig Hoffmann disease may seek genetic testing prenatally. Testing tissue from a developing fetus can also show whether it has this condition.
Other diagnostic tests
- electromyography (EMG) tests
- muscle biopsy
- nerve conduction tests
- additional blood tests
Receiving a diagnosis may require several visits to different clinicians. However, it is necessary to conduct these tests to ensure that each person receives an accurate diagnosis.
There is currently no cure for Werdnig Hoffmann disease.
Because infants with Werdnig Hoffmann disease experience muscle weakness, they
These infants may also need breathing support. A ventilator can assist with breathing, which becomes harder as symptoms progress. Similarly, feeding tubes can help provide nutrients for infants who cannot eat independently.
Although there is no cure for this condition, new studies are looking into gene therapy as a potential treatment. A
The researchers found that children who received gene therapy showed improvement in their symptoms. In the future, new gene therapies could further improve outcomes for people with Werdnig Hoffmann disease.
Learn more about treatment for spinal muscular atrophy here.
About 74 in 100 infants with Werdnig Hoffmann disease will receive a diagnosis within the first 2 months of life. The remaining 26% should receive this diagnosis by the age of 6 months.
Infants who present with clear signs of disease at birth typically survive for around 3 months. Those who develop symptoms within 2 months generally survive between 4 and 8 months. Most children with Werdnig Hoffmann disease will not survive for more than 18 months.
Breathing and nutritional support can help increase survival rates for these infants. Ultimately, breathing complications are the most common cause of death from Werdnig Hoffmann disease.
Learn more about life expectancy for spinal muscular atrophy here.
The most common complications of Werdnig Hoffmann disease are respiratory problems. Many infants with this condition have trouble breathing. They may later develop respiratory infections such as pneumonia.
A person with Werdnig Hoffmann disease also experiences feeding difficulties. They may be unable to swallow independently and require a feeding tube.
This disease can also cause scoliosis, a condition that involves curvature of the spine. It can also lead to shortened muscles that limit movement and joint mobility.
Werdnig Hoffmann disease is the most severe form of spinal muscular atrophy. The other types of conditions in this group
- Spinal muscular atrophy type 2: Children with type 2 typically exhibit symptoms between 6 and 18 months old. They also experience muscle weakness, difficulty breathing, and trouble walking without support. Although life expectancy varies, a person with type 2 can survive into adulthood.
- Spinal muscular atrophy type 3: Also known as Kugelberg-Welander disease, this condition presents after the age of 18 months. Children with type 3 may exhibit muscle weakness, shortened muscles or tendons, and scoliosis. With proper care, a person with type 3 can experience a typical lifespan.
- Spinal muscular atrophy type 4: This condition leads to symptoms that occur in adulthood. The symptoms of this type are generally mild and do not reduce life expectancy.
Werdnig Hoffmann disease is a severe form of spinal muscular atrophy. Infants with this condition generally receive a diagnosis by six months of age.
There is currently no cure for this disease, and children do not typically survive for longer than 18 months.
New research suggests that gene therapy may help treat or cure Werdnig Hoffmann disease in the future. Additional studies into gene therapy may offer better outlooks in the future for children with this disease.