Batten Disease is the most common form of a group of disorders called Neuronal Ceroid Lipofuscinoses (or NCLs). Although Batten Disease is usually regarded as the juvenile form of NCL, it has now become the term to encompass all forms of NCL. Batten Disease/NCL is relatively rare, occurring in an estimated 2 to 4 of every 100,000 births in the United States but no one really knows how many children there may be in North America or anywhere else in the world. The diseases have been identified worldwide. Although NCLs are classified as rare diseases, they often strike more than one person in families that carry the defective gene. The forms of NCL are classified by age of onset and have the same basic cause, progression and outcome but are all genetically different, meaning each is the result of a different gene. There are four main types of NCL, including two forms that begin earlier in childhood and a very rare form that strikes adults. The symptoms are similar but they become apparent at different ages and progress at different rates.
Forms of NCL/Batten Disease:
- Infantile NCL (Santavuori-Haltia disease): begins between about 6 months and 2 years of age and progresses rapidly. Affected children fail to thrive and have abnormally small heads (microcephaly). Also typical are short, sharp muscle contractions called myoclonic jerks. Initial signs of this disorder include delayed psychomotor development with progressive deterioration, other motor disorders, or seizures. The infantile form has the most rapid progression and children live into their mid childhood years.
- Late Infantile NCL (Jansky-Bielschowsky disease): begins between ages 2 and 4. The typical early signs are loss of muscle coordination (ataxia) and seizures along with progressive mental deterioration.. This form progresses rapidly and ends in death between ages 8 and 12.
- Juvenile NCL (Batten Disease): begins between the ages of 5 and 8 years of age. The typical early signs are progressive vision loss, seizures, ataxia or clumsiness. This form progresses less rapidly and ends in death in the late teens or early 20s, although some may live into their 30s.
- Adult NCL (Kufs Disease or Parry's Disease): generally begins before the age of 40, causes milder symptoms that progress slowly, and does not cause blindness. Although age of death is variable among affected individuals, this form does shorten life expectancy.
Over time, affected children suffer mental impairment, worsening seizures, and progressive loss of sight and motor skills. Eventually, children with Batten Disease/NCL become blind, bedridden, and unable to communicate and it is presently always fatal.
Diagnostic tests used for Batten Disease/NCLs include:
- Skin or tissue sampling. The doctor can examine a small piece of tissue under an electron microscope. The powerful magnification of the microscope helps the doctor spot typical NCL deposits. These deposits are found in many different tissues, including skin, muscle, conjunctiva, rectal and others. Blood can also be used. See inclusion body pictures in question above.
- Electroencephalogram or EEG. An EEG uses special patches placed on the scalp to record electrical currents inside the brain. This helps doctors see telltale patterns in the brain's electrical activity that suggest a patient has seizures.
- Electrical studies of the eyes. These tests, which include visual-evoked responses (VER) and electro-retinagrams (ERG), can detect various eye problems common in childhood Batten Disease/NCLs.
- Brain scans. Imaging can help doctors look for changes in the brain's appearance. The most commonly used imaging technique is computed tomography (CT), which uses x-rays and a computer to create a sophisticated picture of the brain's tissues and structures. A CT scan may reveal brain areas that are decaying in NCL patients. A second imaging technique that is increasingly common is magnetic resonance imaging, or MRI. MRI uses a combination of magnetic fields and radio waves, instead of radiation, to create a picture of the brain.
- Enzyme assay. A recent development in diagnosis of Batten Disease/NCL is the use of enzyme assays that look for specific missing lysosomal enzymes for Infantile and Late Infantile only. This is a quick and easy diagnostic test. Genetic/DNA testing. Each 'form' of Batten disease is the result of a different gene. Genes for eight of the ten forms have been identified. Testing for these is available for diagnosis as well as carrier and prenatal status.
As yet, no specific treatment is known that can halt or reverse the symptoms of Batten Disease/NCL. However, seizures can be reduced or controlled with anticonvulsant drugs, and other medical problems can be treated appropriately as they arise. At the same time, physical and occupational therapy may help patients retain function as long as possible.
The Batten Disease Support and Research Association enables affected children, adults, and families to share common concerns and experiences. Meanwhile, scientists pursue medical research that will someday yield an effective treatment.
Contributed by MOM Jennifer Medley