What You Need to Know About Batten Disease

Batten disease is a class of rare, fatal genetic disorders that affect the nervous system.

Batten disease is caused when mutations in genes affect very small parts of cells called lysosomes. The lysosomes break down wastes within the cell so they can be discarded or recycled. When this discarding or recycling process is disrupted, it causes a buildup of cellular waste that, in turn, causes symptoms in the body.

Children and adults who have Batten disease may not notice signs of it until they develop worsening symptoms.

The timeframe for when symptoms develop varies greatly depending on the subtype of Batten disease that a person has. And what may start out as mild symptoms may get progressively more serious with time.

For babies and young children, Batten disease may eventually lead to death, according to the National Institute of Neurological Disorders and Stroke (NINDS). When the condition has a later onset or comes about in adulthood, it may not affect a person’s overall life expectancy.

Symptoms of Batten disease range in severity and can start at almost any age – from soon after birth to adulthood.

Early symptoms include:

• seizures
• worsening eyesight
• developmental delays or issues with learning
• loss of previous skills
• dementia
• trouble with balance or movement

As the condition progresses, symptoms may worsen and include:

• mood or behavior changes
• sleep concerns
• movement or gross motor issues
• muscle spasms or tics
• confusion
• learning difficulties
• total vision loss
• heart concerns
• paralysis
• parkinsonism (movement issues)
• spasticity (muscle stiffness)

Batten disease is an inherited disorder, also called a hereditary disorder. This is when a defect in the parents’ genes gets passed down to their child.

The gene that causes Batten disease is autosomal recessive. This means it does not cause symptoms unless a person inherits the disease-causing gene from both parents.

If a person has only one copy of the gene, they would not have symptoms. Yet they would still be a carrier of the condition because they can pass the gene to their child.

According to NINDS, parents who are both carriers of the disease-causing gene have a:

• 1 in 4 (25 percent) chance of having a child with Batten disease
• 2 in 4 (50 percent) chance their child will be a carrier of Batten disease
• 1 in 4 (25 percent) chance their child will inherit only “normal” genes

There are 13 types of Batten disease. Each is classified according to the affected gene that causes it, such as CLN1, CLN2, and so on.

Other important things to note are:

• the age of onset
• symptoms and their severity
• the rate at which those symptoms progress, or worsen

Usually, people who develop Batten disease have inherited two copies of the same mutation. In rare cases, a person can inherit two different mutations and may develop a milder form of the condition, especially in the adult-onset forms, according to NINDS.

The 13 types of Batten disease include:

CLN1 (infantile onset)

Symptoms typically develop before a child turns 12 months old. As a result, the child may not learn to stand, walk, or talk or may lose those skills rapidly. By 2 years old, the child may be blind. By 3 years old, the child may need a feeding tube and full-time care. Life expectancy generally does not extend beyond mid-childhood.

CLN1 (juvenile onset)

This subtype develops between ages 5 and 6. The progression of symptoms is generally slower and includes the same symptoms as in the infantile-onset subtype. Children may live to adolescence or, with even later onset, to adulthood.

CLN2 (late infantile onset)

Symptoms develop by the time a child turns 2 years old and include things like seizures, trouble walking, and trouble talking. Muscle spasms (called myoclonic jerks) may develop by the time a child is between 4 and 5 years old. As symptoms worsen, children become more dependent on caregivers. Life expectancy is between 6 and 12 years old.

CLN2 (juvenile onset)

Ataxia, or loss of coordination, is typically the first sign of this subtype. It affects children starting around age 6 or 7. Children may live through their teen years.

CLN3 (juvenile onset)

With this subtype, children between 4 and 7 years old may rapidly lose their eyesight. Seizures and learning and behavior issues begin by the time a child reaches age 10. Movement issues follow for older children and teenagers. Life expectancy is between 15 and 30 years.

CLN4 (adult onset)

This rare subtype doesn’t appear until a person reaches adulthood, around age 30. It is marked by dementia and movement issues and does not necessarily affect life expectancy.

CLN5 (late infantile onset)

While children may develop at an expected rate in their first years of life, behavior issues and loss of motor skills may appear by the time a child is between 6 and 13 years old. Additional symptoms include seizures, muscle spasms, and vision loss. Children may live into their teens, but they may need a feeding tube or other support.

CLN6 (late infantile onset)

Seizures, behavioral changes, and developmental delays may become apparent in the preschool years with this subtype. Children may lose previous skills, like speaking, walking, and playing. Vision loss, sleep issues, and muscle twitches are also possible. Life expectancy is generally between late childhood and the early teen years.

CLN6 (adult onset)

With onset in early adulthood, this subtype affects muscle control in the arms and legs and may cause seizures. As a result, a person may have trouble walking or with motion in general. Another characteristic of this subtype is a slow cognitive decline.

CLN7 (late infantile onset)

Onset is between ages 3 and 7 and is marked by seizures or epilepsy and loss of developmental skills. As time goes on, a child may also develop muscle twitches and issues with sleeping. With this subtype, there is a notable increase in symptoms when a child is between 9 and 11 years old, but most kids live to their teen years.

CLN8 EPMR (juvenile onset)

EPMR stands for “epilepsy with progressive mental retardation.” With this subtype, children experience seizures, cognitive decline, and sometimes a loss of speech starting between ages 5 and 10. The seizures may become less frequent as a child gets older. Children may live into adulthood.

CLN8 (late variant onset)

Symptom onset for this subtype is sometime between 2 and 7 years old. Primary symptoms include vision loss, issues with cognition, treatment-resistant epilepsy, changes in behavior, and muscle twitches. Issues with cognition tend to get worse around age 10. Life expectancy is variable, with some people living into their 20s.

CLN10

This very rare subtype can have an onset at birth, childhood, or adulthood. Some children may have a small head (microcephaly). This subtype can be further divided into two different forms:

• Congenital. Seizures appear before birth or soon after birth. Other symptoms include issues with breathing or with sleep apnea. Life expectancy is short — only a few weeks after birth.
• Late infantile. Seizures, vision loss, and issues with balance and cognition are characteristic of this form. It has a later onset and a slower progression than congenital. Life expectancy is generally not beyond childhood.

Batten disease is most commonly diagnosed using genetic testing, according to NINDS.

Your doctor may order genetic tests after recording your child’s medical history, hearing their family health history, and observing certain signs or characteristics of the disorder.

Other tests that may be used for diagnosing Batten disease include:

• Enzyme activity measurement: helps confirm or rule out CLN1 and CLN2 type Batten disease
• Skin or tissue sampling: may help discover skin and tissue changes consistent with Batten disease
• Blood or urine testing: can detect changes that may indicate the presence of Batten disease

These tests may be used to diagnose and monitor the effects of Batten disease:

• Electroencephalogram (EEG). An EEG may show the brain’s electrical activity that indicates seizures or other electrical patterns that may be caused by Batten disease.
• Imaging tests. CT scans and MRI scans can help see changes in the brain that may result from Batten disease.

Vision loss is an early symptom of many subtypes. Experts share that an eye exam may help detect Batten disease in its early form by noting the loss of cells inside the eyes. These results should be confirmed with further testing.

There is no cure for Batten disease, per NINDS. Treatment generally cannot reverse the progression of the disease and is, instead, focused on addressing symptoms and improving quality of life.

That said, the Food and Drug Administration (FDA) has approved a treatment for the CLN2 subtype. It is an enzyme replacement therapy that goes by the name of cerliponase alfa (Brineura). This treatment may slow or even stop the progression of this subtype of Batten disease — but only this subtype and no others.

Other treatment options for symptoms might include:

• antiseizure medications
• depression or anxiety medications
• medications to treat parkinsonism
• medications to treat spasticity
• physical therapy and occupational therapy

The outlook for Batten disease depends on the subtype and the individual person who has the condition.

Some subtypes have an aggressive progression and result in shorter life expectancy. Others bring about symptoms more slowly and may result in a longer life expectancy.

Individuals who deal with any subtype will likely need frequent medical care and additional support with everyday tasks. Many forms of Batten disease can lead to a person being unable to walk, talk, see, eat, or take care of themselves.

While this condition does not have a cure, there are various treatments available that can improve your child’s quality of life and comfort. In some cases, treatment may even slow or stop the disease progression.

If your child has been diagnosed with Batten disease, your doctor can give you more details about the subtype and the outlook specific to that subtype.

If you’re a caregiver for someone with Batten disease, you are not alone. Reach out to your doctor to find support near you. In addition, the Batten Disease Support & Research Association website provides resources to find support both in person and online.