Batten disease, along with other forms of neuronal ceroid lipofuscinoses (NCL) affect an estimated 1 in 100,000 individuals worldwide. It can occur with greater frequency in families of Northern European Scandinavian ancestry; in particular, those of Swedish heritage. It is thought to affect one in 25, 000 infants in northern Europe. Juvenile Batten Disease is the most common form of NCL.

Most cases of Batten disease are caused by mutations in the CLN3 gene. This gene provides instructions for making a protein whose function is unknown, although it is localized to lysosomes (see definition below). It is unclear how these mutations lead to the features of Batten disease. These mutations somehow disrupt the function of cellular structures called lysosomes, which are compartments in the cell that normally digest and recycle different types of molecules. The malfunction of lysosomes leads to a buildup of fatty substances called lipopigments within the cell structures. These occur throughout the body, with neurons in the brain being particularly vulnerable to the damage. The progressive death of cells, especially in the brain, leads to vision loss, seizures, and intellectual decline in people with Batten disease.

Only a small percentage of cases are caused by mutations in other genes. Many of these genes are also involved in lysosomal function.

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

The symptoms typically appear between 5 and 15 years of age. Affected children may develop slowly progressive vision abnormalities, behavioural changes, and intellectual decline. An early finding in Batten disease is progressive loss of vision characterized macular degeneration, deterioration of the nerves of the eye (optic nerves) that transmit impulses from the membrane lining the eyes (retina) to the brain (optic atrophy), and abnormal accumulation of colored (pigmented) material on the retinas. Children with Batten disease often lose their sight by the age of 10 years old. In some, the first signs are seizures and the loss of previously acquired physical and mental abilities (developmental regression). As these individuals age, seizures worsen, signs of dementia become apparent, and motor abnormalities develop. During this period, behavioural and personality changes often occur. This include mood disturbances, psychotic states, anxiety, and hallucinations. Speech disturbances may also occur. During the late teens or twenties, additional abnormalities develop such as sudden involuntary muscle contractions (myoclonus), muscle spasms (spasticity) that result in slow, stiff movement of the legs, weakness or paralysis of all four limbs (quadriparesis), and sleep disturbance. Typically, progressive neurological and mental degeneration leaves affected individuals bedridden and unable to communicate easily. This eventually results in life-threatening complications by the twenties.

In many cases, Batten disease is initially observed by an ophthalmologist because one of the first symptoms is vision loss. A diagnosis may be made through a thorough clinical evaluation, detailed patient history and identification of characteristic physical findings. During the initial stage of the disease; retinitis pigmentosa may be suspected. Later in the disease course, the differential diagnosis may also include other causes of dementia and seizures at school age, such as mitochondrial disorders.

A variety of specialized tests aid the diagnosis of Batten disease. This includes microscopic examination and study of the chemical components of samples of tissue (biopsy), usually from the skin. The study of such samples reveals abnormal accumulations of deposits (i.e. pigmented lipids ceroid and lipofuscin) in membrane-bound cavities within the body of cells. In Batten disease, these have a characteristic appearance, like fingerprints. Similar deposits may also be present in other tissues and cells of the body (e.g. certain white blood cells [lymphocytes]). Other tests include blood or urine tests, electroencephalogram or EEG (suggests if an individual has seizures), electrical studies of the eyes (which detect various eye problems common in Batten disease), diagnostic imaging using CT or MRI, measurement of enzyme activity, and DNA analysis (confirms the diagnosis or provides a prenatal diagnosis of Batten disease).

The treatment of Batten disease is directed toward the specific symptoms that are apparent in each affected individual. Treatment will most likely require the coordinated efforts of a team of specialists such as pediatricians, neurologists, ophthalmologists, physical therapists, psychiatrists, etc. Specific therapies for Batten disease are symptomatic and supportive. In some cases, treatment with anticonvulsant drugs such as lamotrigine and valproate may help prevent, reduce, or control various types of seizures. Medications may also be used to help with psychiatric symptoms such as hallucinations. Early intervention is important to ensure the affected children reach their potential. Special services may be beneficial as well such as special social support, special remedial education, and other medical, social, and/or vocational services. Genetic counseling may be beneficial to affected individual and families.

The prognosis for Batten disease is severe, but life expectancy varies. Life expectancy generally ranges from the late teens to the 30's. Some patients can live into their 40’s.

Batten disease will greatly impact the patient and the patient’s family. In rare and currently incurable diseases such as Batten disease, lack of a diagnosis or misdiagnosis increases family stress and is expensive, time consuming, can result in mistreatment, and prevents access to effective family and medical support services. It is recommended to get diagnostic testing, health management, and genetic counseling services for Batten disease if it is suspected.

GHR: http://ghr.nlm.nih.gov/condition/juvenile-batten-disease

Orphanet: http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=79264

ORDR: https://rarediseases.info.nih.gov/gard/5897/batten-disease/resources/1

NORD: https://rarediseases.org/rare-diseases/batten-disease/

OMIM: http://www.omim.org/entry/204200?search=batten%20disease&highlight=batten%20disease

Wikipedia: https://en.wikipedia.org/wiki/Batten_disease

Beyond Batten Disease Foundation: http://beyondbatten.org/understanding-batten/living-with-batten/