CLN5 Subtype of Batten Signs and Symptoms
CLN5 is a subtype of Batten diseaseBatten disease is the common name for a broad class of rare, inherited disorders or diseases of the nervous system also known as neuronal ceroid lipofuscinoses, or NCLs. In these diseases, a defect in a specific gene triggers a cascade of problems that interferes with a cell’s ability to recycle certain molecules. The disease has several forms that share some of the same features and symptoms but vary in severity and age when symptoms first begin to appear. Each form is caused by a variant in a different gene. Although “Batten disease” originally referred specifically to the juvenile-onset form of NCL, the term Batten disease is increasingly used to describe all forms of NCL. The disease ultimately leads to shortened lifespan. with late infantile onset, which means that the signs and symptoms of CLN5 begin to show during childhood years. Children living with CLN5 will often experience normal development, until they reach the ages between 4 and 7 years old, when the first signs and symptoms of the disease typically appear. After disease onset occurs, the symptoms will continue to progress.
Birth Through Age 7
Children with CLN5 typically experience normal development until they reach the ages between 4-7. Initial common signs and symptoms may include:
- Cognitive difficulties
- Initial delays with learning
- Delays with motor function and movement
- Loss of motor skills that were previously acquired (developmental regressionWhen a child loses an acquired function, milestone or fails to progress beyond a prolonged plateau after a period of relatively normal development.)
Adolescent years
As the disease continues to progress through adolescent years, other symptoms may become apparent:
- Vision deterioration
- Progressive dementiaThe loss of cognitive functioning which includes thinking, remembering, and reasoning which result in behavioral issues that interfere with an individual’s daily life.
- Decline in language ability
- Difficulty eating
- Loss of motor function
Challenges with cognitive and motor skills may be perceived as behavioral issues such as hyperactivityA condition of being overly active., anxiety, and obsessive activities. The child’s description of vision loss associated with CLN5 may be interpreted as hallucinations by parents or caregivers.
Childhood Years
Signs and symptoms start to become most noticeable during this stage. The signs that are most commonly seen during this time may include:
- Continued learning disabilities, including struggles with concentration and memory issues
- Vision problems or impairments
- Recurrent seizures, or epilepsy
- Uncontrollable muscle jerks (myoclonusBrief, shock-like jerks or twitching of a muscle (myoclonus).)
- Motor clumsiness
- Difficulty coordinating movements
“Austin’s perception would be off. Sometimes he would run into a doorframe, or put his foot down to search before stepping down a stair. When he was on an uneven service, he would have trouble walking. Walking up and down hills, or going from sidewalk to grass, got increasingly difficult for him.”
- Wendy, mother of son living with CLN5
Birth Through Age 7
Children with CLN5 typically experience normal development until they reach the ages between 4-7. Initial common signs and symptoms may include:
- Cognitive difficulties
- Initial delays with learning
- Delays with motor function and movement
- Loss of motor skills that were previously acquired (developmental regression)
I didn’t notice any initial signs and symptoms because I was unsure of what I was looking for and he kept getting misdiagnosed.
- Wendy, mother of son living with CLN5
Childhood Years
Signs and symptoms start to become most noticeable during this stage. The signs that are most commonly seen during this time may include:
- Continued learning disabilities, including struggles with concentration and memory issues
- Vision problems or impairments
- Recurrent seizures, or epilepsy
- Uncontrollable muscle jerks (myoclonus)
- Motor clumsiness
- Difficulty coordinating movements
“Austin’s perception would be off. Sometimes he would run into a doorframe, or put his foot down to search before stepping down a stair. When he was on an uneven service, he would have trouble walking. Walking up and down hills, or going from sidewalk to grass, got increasingly difficult for him.”
- Wendy, mother of son living with CLN5
Adolescent years
As the disease continues to progress through adolescent years, other symptoms may become apparent:
- Vision deterioration
- Progressive dementia
- Decline in language ability
- Difficulty eating
- Loss of motor function
Challenges with cognitive and motor skills may be perceived as behavioral issues such as hyperactivity, anxiety, and obsessive activities. The child’s description of vision loss associated with CLN5 may be interpreted as hallucinations by parents or caregivers.
Signs & Symptoms Reported by Caregivers
While the signs, symptoms, and age of onset of CLN5 may vary and can progress differently in each individual, there are common signs and symptoms that are consistent across people living with CLN5. The examples below come from parents of children with CLN5.
- Progressive vision loss (reluctance to step off curbs, squinting to look at pictures, reads a book too close to face, sees things that aren’t there, especially at night)
- Cognitive delay (isn’t meeting milestones, slow to respond verbally)
- Seizures (appearing to nod off, looks like they are startled awake, twitches and tremors)
- Clumsiness and issues with gross motor function or coordination of movement (lack of agility, reluctance to run, difficulty hopping on one foot, tripping, and falling)
- Deterioration of fine motor skills (challenges with scissors, needing a fat crayon instead of a pencil, difficulty picking up small objects)
Sources:
- Neuronal ceroid lipofuscinosis 5 (n.d.). Retrieved August 16, 2019, from link.
- Batten DiseaseBatten disease is the common name for a broad class of rare, inherited disorders or diseases of the nervous system also known as neuronal ceroid lipofuscinoses, or NCLs. In these diseases, a defect in a specific gene triggers a cascade of problems that interferes with a cell’s ability to recycle certain molecules. The disease has several forms that share some of the same features and symptoms but vary in severity and age when symptoms first begin to appear. Each form is caused by a variant in a different gene. Although “Batten disease” originally referred specifically to the juvenile-onset form of NCL, the term Batten disease is increasingly used to describe all forms of NCL. The disease ultimately leads to shortened lifespan. Fact Sheet. (2019, June 24). Retrieved July 31, 2019, from link.
- Batten Disease Support and Research Association CLN5 disease. (n.d.). Retrieved August 16, 2019, from link.
- Malhas, A. Study Provides More Insight into Early Signs, Progression of CLN5 Disease. (n.d.). Retrieved August 16, 2019, from link.
- CEROID LIPOFUSCINOSIS, NEURONAL, 5; CLN5. (2016, March 15). Retrieved June 20, 2019, from link.
- Simonati, A., Williams, R. E., Nardocci, N., Laine, M., Battini, R., Schulz, A., Garavaglia, B., Moro, F., Pezzini, F., & Santorelli, F.M. (2017). Phenotype and natural history of variantA variant is a change in DNA. A variant may or may not cause disease. The following modifiers describe the variant: (i) pathogenic, (ii) likely pathogenic, (iii) uncertain significance, (iv) likely benign, or (v) benign depending on whether or not the variant causes disease. For example, a “pathogenic variant” may cause disease. The term “variant” has replaced the term “mutation.” late infantile ceroid‐lipofuscinosis 5. Developmental Medicine & Child Neurology, 59(8): 815-821. Retrieved December 17, 2019, from link.
