Childhood dementia explained: symptoms, diagnosis and hope for new treatments

What is childhood dementia?

Childhood dementia is an umbrella term covering between 100 and 140 rare genetic disorders, including Batten disease, Niemann Pick, Sanfilippo syndrome and Rett syndrome. Each condition is rare on its own, but together childhood dementias are as common as childhood cancers.

Most of us will have friends or family members affected by dementia. The term is linked to several conditions that often appear with ageing. Although definitions vary, dementia generally means a gradual loss of cognitive abilities. This includes difficulty recalling memories or forming new ones, problems with decision making, language, spatial awareness, and sometimes fine motor skills, such as using cutlery.

Well known examples include Alzheimer’s disease, frontotemporal dementia and vascular dementia. Some forms have genetic links, but for most we still do not know the exact cause. We can identify certain disease markers, like abnormal protein build up, but we do not yet understand what triggers these changes.

Childhood dementias share many of these features. Children may develop memory loss, confusion, loss of speech, declining motor skills and behavioural changes.

The key differences are the early age of onset and the rapid progression, which often leads to severely shortened lifespans.

What are the signs and symptoms of childhood dementia?

Because childhood dementia includes many different genetic disorders, the symptoms can look quite different from one child to another. These conditions affect how cells work, including how they produce energy and how they break down things like sugars and fats and recycle waste products.

When these basic processes go wrong, the brain is especially affected. This means children may show early problems with language, or they may begin to lose their vision, but difficulties with thinking and learning are always at the centre of the condition.

Challenges diagnosing childhood dementia

Diagnosing childhood dementia is extremely difficult. Although these conditions are collectively more common than most people realise, each individual disorder is very rare. There are so many different forms, each with its own pattern of symptoms and timing, and diagnosis can be slow and complicated. Most doctors in the UK will never see a case, and it is unrealistic to expect them to recognise every possible condition.

Batten disease is a good example. It is not one illness but a group of 13 or 14 related disorders that affect the lysosome, the cell’s waste recycling system. Because lysosomes are found in every cell, symptoms can appear across the whole body. Many children first lose their vision, then gradually develop memory problems, movement difficulties and sometimes seizures, before facing an early death. In some forms, early symptoms often resemble more common eye conditions, so children may first be diagnosed with retinopathy and later with a learning difficulty.

Statistically, doctors are far more likely to encounter two separate common conditions than one rare disease that causes many different problems, which makes the diagnostic journey even harder. Families often become experts out of necessity, and children are rarely diagnosed before symptoms appear unless an older sibling has already been correctly identified.

The positive news is that full genome sequencing could make diagnosis much easier. Current newborn screening, such as the heel prick test, only checks for a small number of specific conditions, and many childhood dementias are not included. Spinal Muscular Atrophy, for example - a childhood form of motor neuron disease - was only recently added in the UK.

Genome sequencing would allow doctors to spot known disease causing mutations early. Timing is crucial: the sooner a condition is identified, the sooner families can receive the right care, support and symptom management. When new treatments become available, early intervention will offer the best chance of improving outcomes.

How does childhood dementia differ from adult dementia?

A major difference between childhood dementia and adult dementia is the cause. Childhood dementias are driven by single genetic mutations that disrupt essential cellular systems. These systems are so fundamental that they are shared across many species, which means scientists can model the diseases more accurately in cells and animals and design targeted treatments. Because the underlying biological processes overlap with those seen in adult neurodegeneration, discoveries in childhood dementia research may also help shape future treatments for adult onset conditions.

One in 2,900 babies is born with a genetic change that will lead to childhood dementia, and half of these children will die before the age of ten. Some parts of the world have higher rates of certain types of childhood dementia, often because communities historically had little movement in or out. For example, the CLN3 form of Batten disease is more common in Finland.

In Scotland, more children live with childhood dementia than with childhood cancer, yet the condition remains largely unseen by the public, professionals and policymakers. At the moment, only Australia and the Scottish government officially recognise childhood dementia as its own disease category in planning and legislation.

How is childhood dementia treated?

Right now, most treatments for childhood dementia focus only on managing symptoms. Because these conditions are caused by faults in specific genes, researchers are exploring three main types of targeted therapies.

The first approach is gene therapy, which aims to replace or correct the faulty gene. Scientists can use harmless versions of viruses to deliver healthy genetic material into cells. Viruses, some of which are related to the common cold can carry a working copy of the gene without becoming part of the child’s DNA. Different viruses used as a therapy delivery tool have stronger effects in different tissues. For example, some will work best in tissues where cells divide regularly, such as the liver, gut or lungs. Clinical trials using such viral tools are already underway for some forms of Batten disease.

The second approach is enzyme replacement therapy. Some faulty genes fail to produce a working enzyme, so scientists can make the missing enzyme in the lab and infuse it into the child. This treatment must be repeated because the body uses up the enzyme. In CLN2 Batten disease, children receive therapy every two weeks into the nervous system. It is not a cure, but it can slow or halt disease progression. However, the cost of lifelong infusions is extremely high, and not sustainable for healthcare systems such as the NHS.

The third option is gene‑edited cell therapy. Doctors can take a child’s own cells, repair the faulty DNA, and return the corrected cells so they can produce the missing protein. This approach only works for certain genetic faults but has strong potential. New therapies are beginning to appear. A recent example is a breakthrough treatment for Hunter syndrome, where a child responded remarkably well to a world‑first cell based gene therapy.

We now have the scientific tools to develop treatments for childhood dementia—far more than we had even 20 years ago.

The biggest challenges are funding, keeping therapy development moving consistently, and finding reliable biological markers that show how each condition progresses and whether a new treatment is working.

What does the research show?

Better ways to diagnose, treat and monitor the disease depends on many different types of expertise working together. No single institution has all the knowledge and skills needed to do this alone.

Nottingham Trent University research, in partnership with other national and international disease experts, focuses on finding new treatment options. One part of this involves looking at medicines already used for other diseases to see whether they could be repurposed to slow childhood dementia. These treatments would not cure the condition but might help delay progression, although they would need to be given throughout a child’s life.

We also work on scaling up new therapies that have shown promise in rodent studies, testing whether they can work safely and effectively in humans. For viral gene therapies, the hope is that one treatment could be enough to correct the problem. For enzyme‑based therapies, the best outcome would be slowing or halting the disease, but children would still need regular infusions.

Another key part of our work is identifying biological changes that track how the disease progresses, also known as “biomarkers”. These might include visible changes in brain structure on MRI scans. They are essential because young children cannot reliably describe how they feel, and parents may understandably struggle to judge changes without bias. Biomarkers give an independent, objective measure of whether a disease is worsening or whether a treatment is helping.

We also work to raise awareness and influence policy. Childhood dementia is more common than people realise, yet public understanding is very low. In Scotland, more children live with childhood dementia than childhood cancer. We collaborate with families and charities, who have submitted documents to government calling for formal recognition and support, including contributions to Scotland’s 10‑year national dementia strategy.

We work with an international group of experts and companies who are deeply committed to supporting children with childhood dementia. Many of our colleagues study several conditions at once, and we stay connected with patients, families and charities.