The Batten's disease , Also known as juvenile ceroid ceroid lipofuscinosis, is a pathology Potentially deadly, of genetic origin, which fundamentally affects the nervous system (Cleveland Clinic, 2016).
At the genetic level, most cases are due to the presence of a mutation in the gene CLN3 , Located on chromosome 16 (Mareque Rivas, 2008). As a consequence, there is a systematic and progressive accumulation of proteins and fatty substances in different body tissues (Cleveland Clinic, 2016).
As for its clinical course, Batten disease generates a regression of the development, characterized by the loss of vision, cognitive deterioration, ataxia And even premature death (Andrade-Bañuelos et al., 2012).
Diagnosis is usually made in the final stage of childhood or early adolescence, based on clinical findings. Generally, the Visual deficit is the earliest sign of the pathology, being suspected through an ocular examination.
In addition, a neurological Ophthalmological examination, together with some laboratory tests Electroencephalography And genetic study (Cleveland Clinic, 2016).
There is currently no curative treatment for Batten disease. The therapeutic interventions are oriented to the symptomatic treatment And palliative care, until the death of the affected person occurs (Mareque Rivas, 2008).
Characteristics of Batten disease
Batten's disease is a rare disease, of genetic origin and, in addition, it is a medical condition that is part of pathologies Classified as Lysosomal storage disorders (Batten Disease Support and Research Association, 2016).
In the case of Batten disease, the presence of genetic abnormalities alters the ability of the body's cells to remove substances and waste. In this way, there is an abnormal accumulation of proteins and lipids (fatty substances) (Batten Disease Support and Research Association, 2016).
In Batten disease, the area most commonly affected is the nervous system and, more specifically brain . Because of this, Denominates juvenile ceroid neural lipofuscinosis (National Institutes of Health, 2013).
Thus, this gradual storage of substances will produce serious lesions in cellular function and structure, which leads to progressive deterioration Characteristic of Batten disease (Batten Disease Support and Research Association, 2016).
Specifically, the first description of this pathology was made in 1903, by a British pediatric doctor, Frederick Batten, from whom he received his first name. In addition, this disease is also known as Spielmeyer-Vogt-Sjogren-Batten (National Institute of Neurological Disorders and Stroke, 2015).
About us
Although Batten disease is one of the most common types of Neuronal ceroid lipofuscinosis , Does not present a high prevalence in Comparison with other degenerative and / or neurological diseases (Genetis Home Reference, 2016).
Disorders of the neuronal ceroid lipofuscinosis type show an approximate prevalence of 1 case per 100,000 people in the general population. In addition, although no sex-related differences have been identified, it is a more common disease in Finnish regions where its prevalence Reaches a figure of 1 case per 12,500 people (Genetis Home Reference, 2016).
In the United States, the prevalence of Batten disease and other related disorders has been at least 3 cases per 100,000 Births (National Organization for Rare Disorders, 2007).
Specifically, Batten disease, is part of the set of 6,800 Rare diseases Which affect 30 million people, that is to say almost 1 Every 10 Americans (Beyond Batten Disease Foundation, 2016).
Signs and symptoms
As we have pointed out, Batten disease essentially affects the nervous system, so the most characteristic and frequent signs and symptoms in This pathology, will be related to the neurological area (Genetics Home Referece, 2016).
The clinical pattern of Batten disease is marked by the progressive deterioration of various abilities: vision, cognition, motor, etc. Genetics Home Reference, 2016).
The first signs and symptoms usually appear subtly, especially in the ages between 4 and 8-15 years of age, progressing Rapidly towards a regression of development (Genetics Home Reference, 2016).
Thus, some of the more common clinical findings include (National Organization for Rare Disorders):
Progressive loss of vision
Progressive alteration of visual capacity is one of the earliest symptoms of Batten's disease. It usually starts during the early years Of life and, at around 10 years of age, those affected have partial or total blindness.
Thus, throughout the course of macular and visual degeneration, various pathologies and medical conditions continue to occur, among which we can highlight:
- Macular degeneration : This pathology affects the macula, an ocular region located in the retina. Specifically, this structure is In charge of the control of the central vision, that is to say, that allows us the perception of details with clarity. Thus, degeneration affects Cells thereof, causing its injury and / or destruction and, consequently, progressive deterioration of vision.
- Optic atrophy : This medical condition refers to the progressive deterioration or presence of lesions in the optic nerve. This is Is responsible for the transmission of visual information from the ocular areas to the nervous system, therefore, it is fundamental for the ability Visual efficiency.
- Retinitis Pigmentosa : This pathology is characterized by the presence and accumulation of dark deposits in the retina. Thus, some of The symptoms that it causes is the diminution of the vision in conditions of low light, of the lateral vision and central.
Convulsive Episodes
In other cases, the first symptoms of the disease become visible through the presentation of recurrent seizures.
The International League Against Epilepsy and the International Bureau for Epilepsy define In the seizure as a transient event of signs and / or symptoms due to abnormal, excessive or absent neuronal activity. synchrony.
In addition, we can distinguish two basic types of crisis:
- Focal convulsions : Epileptic events are the product of abnormal activity in a single specific area of the brain, which can With or without loss of consciousness, accompanied by rapid, rhythmic and involuntary movements of different body areas.
- Generalized seizures : Generalized convulsions are those in which the epileptic event, the product of the activity Neuronal abnormality, will affect all or most of the brain areas. In addition, within these, we can distinguish other types:
- Absence crisis : In this type of events, the person who suffers is presented with fixed gaze or with subtle movements Like blinking. When they occur in a group and in succession, they can cause loss of consciousness. They are usually produced in greater proportion in children.
- Tonic seizures : Tonic events are characterized by the development of great muscular rigidity, especially in the Back, arms and legs. In many cases they cause falls to the ground.
- Atonic seizures : Atonic seizures produce a loss of muscle control, therefore, can cause falls.
- Clonic convulsions : Clonic events are characterized by the presence of repetitive and / or repetitive rhythmic muscular movements Abrupt Clonic seizures often affect the neck, face, and arms.
- Myoclonic seizures : Miclonic crises or events develop as sudden and sudden jerks in the arms and legs.
- Tonic-clonic convulsions : Tonic-clonic events, previously known generically as epileptic seizures, Can cause loss of consciousness, muscle stiffness, tremors, loss of sphincter control, etc. Tonic-clonic seizures are the type of event More severe epilepsy.
Cognitive deficits
The accumulation of fatty substances in brain areas and the presence of recurrent seizures produces a significant neurological effect.
In most of the affected, from the first moments can be observed a regression of capacities previously acquired and developed, thus, These symptoms are usually categorized as cognitive impairment.
Mild impairment of cognitive functions may involve deficits in memory, language, impairment of judgment or thinking. TO Some of the most frequent symptoms in the Mild cognitive impairment Are the difficulties to remember names of people, to lose the thread of a Conversation or a significant tendency to lose things. However, they can perform all the activities of their daily life with a degree of effectiveness variable.
On the other hand, when the disease progresses and a degree of severe affection is reached, at the cognitive level, most functions are found Affected: memory , Learning, language, orientation, processing speed, etc.
In addition, this deterioration is usually accompanied by some behavioral alterations and personality changes, mainly related to the state of Mood, anxiety or Psychotic episodes .
Psychomotor Alteration
In the case of the musculoskeletal and motor area, many of the affected can begin to present diverse alterations, some of the most frequent Are related to:
- Hypotonia / Muscle hypertonia : Variable presence of reduced or increased muscle tone.
- Spasticity : Involuntary contraction of various muscle groups, causing tension and muscular rigidity
- Paresthesia : Sensations of burning, numbness, tingling, itching or stinging, which is usually felt in the upper extremities (arms and hands) and Lower (legs and feet).
- Tetraparesis : The affected individuals have significant paralysis in the four limbs of the body.
All these medical events will reduce motor skills and, therefore, will limit the mobility of the affected person. In addition, in In many cases, it is possible to observe motor alterations similar to those Parkinson's disease .
Functional Limitation
As a consequence of all the disorders described above, in the more advanced stages of Batten disease, To be in a situation of total dependency.
Generally, they are in bed, unable to communicate and developing other types of medical complications that can threaten their survival.
Causes
Recent research has shown that the cause of most cases of Batten disease is the presence of Various mutations (interruptions or changes) of the CLN3 gene, located on chromosome 16 (National Organization for Rare Disorders, 2007).
Specifically, this gene is responsible for coding a protein called CLN3, which is located in cell membranes, especially in lysosomes (Recycling centers) and Endosomes (Conveyor Organs) (Bayond Batten Disease Foundation, 2016).
Although the specific function of this protein is not exactly known, Batten disease is related to the pathological accumulation of Fatty material in the tissues of the body, especially the areas of the nervous system (National Institute of Neurological Disorders and Stroke, 2015).
Specifically, the substance that is stored massively is known as lipofuscin, a type of lipopigment, composed of proteins and Fatty substances. These types of substances are usually found in tissues such as the brain, eyes or skin (National Institute of Neurological Disorders and Stroke, 2015)
As a consequence, high levels of this waste substance will lead to the development of important cellular lesions in the affected areas and, Therefore, to the development of the characteristic degeneration of Batten disease (National Institute of Neurological Disorders and Stroke, 2015).
In addition, recent research has also succeeded in identifying a pattern of heritability associated with Batten disease. This pathology has a Genetic pattern Autosomal recessive , So it will be inherited if the affected person has two copies of the altered gene (Genetics Home Reference, 2016).
If a person inherits a single copy of the gene, usually does not show signs and symptoms, therefore, does not develop Batten disease (Genetics Home Reference, 2016).
Diagnosis
The diagnosis of Batten disease is usually made at the infantile stage, the presence of clinical signs and symptoms compatible with this pathology Makes necessary in the use of diverse diagnostic approaches:
- Physical exploration
- Neurological exploration
- Ophthalmologic examination
- Blood analysis
- Urine analysis
- Nerve or skin tissue biopsy
- Electroencephalography
- Genesis Study
In addition to this condition, when the parents know that they have a genetic load compatible with Batten disease, it is possible to perform a Prenatal diagnosis through tests such as amniocentesis or the Sampling of chorionic villi .
Treatment
There is no treatment for Batten disease, as this is a chronic, life-threatening condition.
Although there are some symptoms that can be controlled or reversed, such as seizures, other medical problems with Neurological degeneration (Cleveland Clinic, 2016).
Therapeutic interventions focus on palliative care, physical therapy, Neuropsychology Y Occupational therapy , With the aim of increasing the Quality of life and the survival time of the affected person (Cleveland Clinic, 2016).
References
- Andrade-Bañuelos, A., Jean-Tron, G., Ortega-Ponce, F., Arnold, S., Rana, S., & Islas-García, D. (2012). Childhood Neural Zyroid Lipofuscinosis Late One case report. Anales Médicos, 256-261.
- BBDF. (2016). The juvenile Batten disease gene. Retrieved from the Beyond Batten Disease Foundation.
- BDSRA. (2016). Batten Disease. Retrieved from the Batten Disease Support and Research Association.
- Cleveland Clinic. (2016). Batten Disease. Obtained from Cleveland Clinic.
- Mark Rivas, F. (2008). Juve4nil form of neuronal ceroid lipofuscinosis (Batten's disease). Med Clin (Bar), 676-679.
- NIH. (2015). Batten Disease Fact Sheet. Retrieved from the National Institute of Neurological Disorders and Stroke.
- NIH. (2016). Batten Disease. Retrieved from the Genetics Home Reference.
- NORD. (2007). Batten Disease. Retrieved from the National Organization for Rare Disorders.