Kufs disease

Last updated
Kufs disease
Other namesAdult neuronal ceroid lipofuscinosis, ANCL, Adult NCL

Kufs disease is one of many diseases categorized under a disorder known as neuronal ceroid lipofuscinosis (NCLs) or Batten disease. NCLs are broadly described to create problems with vision, movement and cognitive function. [1] Among all NCLs diseases, Kufs is the only one that does not affect vision, and although this is a distinguishing factor of Kufs, NCLs are typically differentiated by the age at which they appear in a patient. [2]

Contents

Signs and symptoms

Kufs is a neuronal disease, meaning it affects the nervous system, specifically voluntary movement and intellectual function. Symptoms of Kufs can manifest anytime between adolescence and adulthood; however, it usually appears around age 30. There are two types of Kufs: [2] Type A and Type B. Type A causes seizures, myoclonic epilepsy (muscle jerks), dementia, ataxia (compromised muscle coordination), tremors and tics, dysarthria (speech difficulties), confusion, and psychotic behaviour. Although similar to Type A, patients with Type B do not experience myoclonic epilepsy or dysarthria, and they do display changes in personality. Occasionally, patients present with skin disorders causing dryness, roughness, and scaliness. The skin symptoms are a result of keratin buildup in the skin cells (see Genetics for more information). Regardless of the type, most Kufs patients do not survive more than 15 years after their symptoms manifest.[ citation needed ]

Genetics

Type A and Type B Kufs disease are caused by mutations in two sets of different genes. Both gene sets are responsible for producing proteins and enzymes that are heavily involved in protein degradation and excretion in the cell – specifically, the nerve cell.[ citation needed ]

Type A

Mutations to the CLN6 and PPT1 genes result in Kufs disease Type A. [3] CLN6 produces proteins that facilitate fat transport throughout a cell, as well as excretion out of the cell. The PPT1 gene codes for the enzyme palmotoyl-protein thioesterase-1. This enzyme is responsible for removing the fatty-acid side chains off of proteins that have been translocated into the lysozyme. By removing the surrounding fats, palmotoyl-protein thioesterase-1 creates easier access for other enzymes to break down the rest of the protein. Fatty substance build up in the brain is a consequence of the mutated genes. The fats and proteins that build up are called lipopigments. Eventually the buildup of lipopigments results in death of the neuron cells, giving way to the phenotypic symptoms. Type A is an autosomal recessive disease, indicating that it is inherited from the parents. Each parent must carry one copy of the mutation; however, the recessive designation indicates that with only one copy, the parents are not affected, and do not show any symptoms.[ citation needed ]

Type B

Kufs disease Type B is caused by mutations to the DNAJC5 and CTSF genes. [3] This form of Kufs is autosomal dominant, meaning that only one copy of each mutated gene is enough for the disease to manifest. When there is a mutation in the DNAJC5 gene, it affects the production of a cysteine string protein (CSP) that is coded within DNAJC5. [4] CSP aids in transmitting signals through the nerves found in the brain. When the CTSF gene is mutated, it cannot produce Cathepsin F, an enzyme that cuts proteins in the lysosome. [5] By cutting proteins, Cathepsin F can modify the function of the proteins as well as help break them down. Similar to Type A, when both DNAJC5 and CTSF are non-functional, it results in the incomplete breakdown of proteins. Once again, lipopigments build up and brain function is decreased as the neuron cells die.[ citation needed ]

Diagnosis

Diagnosis is usually done by performing genetic analysis (e.g. sequencing, genotyping) when there is reason to suspect Kufs disease. Clinicians may order such tests when the common phenotypes of Kufs disease are observed in patients in order to confirm the diagnosis.[ citation needed ]

Treatment

Kufs disease is managed through supportive care.[ citation needed ]

Related Research Articles

<span class="mw-page-title-main">Lysosomal storage disease</span> Medical condition

Lysosomal storage diseases are a group of over 70 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other parts of the cell for recycling. This process requires several critical enzymes. If one of these enzymes is defective due to a mutation, the large molecules accumulate within the cell, eventually killing it.

Batten disease is a fatal disease of the nervous system that typically begins in childhood. Onset of symptoms is usually between 5 and 10 years of age. Often, it is autosomal recessive. It is the common name for a group of disorders called the neuronal ceroid lipofuscinoses (NCLs).

<span class="mw-page-title-main">Neuronal ceroid lipofuscinosis</span> Medical condition

Neuronal ceroid lipofuscinosis is a family of at least eight genetically separate neurodegenerative lysosomal storage diseases that result from excessive accumulation of lipopigments (lipofuscin) in the body's tissues. These lipopigments are made up of fats and proteins. Their name comes from the word stem "lipo-", which is a variation on lipid, and from the term "pigment", used because the substances take on a greenish-yellow color when viewed under an ultraviolet light microscope. These lipofuscin materials build up in neuronal cells and many organs, including the liver, spleen, myocardium, and kidneys.

Infantile neuronal ceroid lipofuscinoses (INCL) or Santavuori disease or Hagberg–Santavuori disease or Santavuori–Haltia disease or Infantile Finnish type neuronal ceroid lipofuscinosis or Balkan disease is a form of NCL and inherited as a recessive autosomal genetic trait. The disorder is progressive, degenerative and fatal, extremely rare worldwide – with approximately 60 official cases reported by 1982.

Myoclonic epilepsy refers to a family of epilepsies that present with myoclonus. When myoclonic jerks are occasionally associated with abnormal brain wave activity, it can be categorized as myoclonic seizure. If the abnormal brain wave activity is persistent and results from ongoing seizures, then a diagnosis of myoclonic epilepsy may be considered.

<span class="mw-page-title-main">Battenin</span> Protein found in humans

Battenin is a protein that in humans is encoded by the CLN3 gene located on chromosome 16. Battenin is not clustered into any Pfam clan, but it is included in the TCDB suggesting that it is a transporter. In humans, it belongs to the atypical SLCs due to its structural and phylogenetic similarity to other SLC transporters.

Unverricht–Lundborg disease is the most common form of an uncommon group of genetic epilepsy disorders called the progressive myoclonus epilepsies. It is caused due to a mutation in the cystatin B gene (CSTB). The disease is named after Heinrich Unverricht, who first described it in 1891, and Herman Bernhard Lundborg, who researched it in greater detail in 1901 and 1903. ULD onsets in children between the ages of 6 and 16; there are no known cases in which the person was older than 18. Most cases originate from the Baltic region of Europe, though many have been reported from countries in the Mediterranean.

Progressive Myoclonic Epilepsies (PME) are a rare group of inherited neurodegenerative diseases characterized by myoclonus, resistance to treatment, and neurological deterioration. The cause of PME depends largely on the type of PME. Most PMEs are caused by autosomal dominant or recessive and mitochondrial mutations. The location of the mutation also affects the inheritance and treatment of PME. Diagnosing PME is difficult due to their genetic heterogeneity and the lack of a genetic mutation identified in some patients. The prognosis depends largely on the worsening symptoms and failure to respond to treatment. There is no current cure for PME and treatment focuses on managing myoclonus and seizures through antiepileptic medication (AED).

<span class="mw-page-title-main">Palmitoyl(protein) hydrolase</span> Class of enzymes

Palmitoyl protein hydrolase/thioesterases is an enzyme (EC 3.1.2.22) that removes thioester-linked fatty acyl groups such as palmitate from modified cysteine residues in proteins or peptides during lysosomal degradation. It catalyzes the reaction

<span class="mw-page-title-main">Tripeptidyl peptidase I</span> Protein-coding gene in the species Homo sapiens

Tripeptidyl-peptidase 1, also known as Lysosomal pepstatin-insensitive protease, is an enzyme that in humans is encoded by the TPP1 gene, also known as CLN2. TPP1 should not be confused with the TPP1 shelterin protein which protects telomeres and is encoded by the ACD gene. Mutations in the TPP1 gene leads to late-infantile neuronal ceroid lipofuscinosis.

<span class="mw-page-title-main">CLN6</span> Protein-coding gene in humans

Ceroid-lipofuscinosis neuronal protein 6 is a protein that in humans is encoded by the CLN6 gene.

<span class="mw-page-title-main">CLN5</span> Protein-coding gene in humans

Ceroid-lipofuscinosis neuronal protein 5 is a protein that in humans is encoded by the CLN5 gene.

<span class="mw-page-title-main">CLN8</span> Protein-coding gene in humans

Protein CLN8 is a protein that in humans is encoded by the CLN8 gene.

<span class="mw-page-title-main">PPT1</span> Protein-coding gene in the species Homo sapiens

Palmitoyl-protein thioesterase 1 (PPT-1), also known as palmitoyl-protein hydrolase 1, is an enzyme that in humans is encoded by the PPT1 gene.

<span class="mw-page-title-main">Jansky–Bielschowsky disease</span> Medical condition

Jansky–Bielschowsky disease is an extremely rare autosomal recessive genetic disorder that is part of the neuronal ceroid lipofuscinosis (NCL) family of neurodegenerative disorders. It is caused by the accumulation of lipopigments in the body due to a deficiency in tripeptidyl peptidase I as a result of a mutation in the TPP1 gene. Symptoms appear between ages 2 and 4 and consist of typical neurodegenerative complications: loss of muscle function (ataxia), drug resistant seizures (epilepsy), apraxia, development of muscle twitches (myoclonus), and vision impairment. This late-infantile form of the disease progresses rapidly once symptoms are onset and ends in death between age 8 and teens. The prevalence of Jansky–Bielschowsky disease is unknown; however, NCL collectively affects an estimated 1 in 100,000 individuals worldwide. Jansky–Bielschowsky disease is related to late-infantile Batten disease and LINCL, and is under the umbrella of neuronal ceroid lipofuscinosis.

<span class="mw-page-title-main">Galactosialidosis</span> Rare disease

Galactosialidosis, also known as neuraminidase deficiency with beta-galactosidase deficiency, is a genetic lysosomal storage disease. It is caused by a mutation in the CTSA gene which leads to a deficiency of enzymes β-galactosidase and neuraminidase. This deficiency inhibits the lysosomes of cells from functioning properly, resulting in the accumulation of toxic matter within the cell. Hallmark symptoms include abnormal spinal structure, vision problems, coarse facial features, hearing impairment, and intellectual disability. Because galactosialidosis involves the lysosomes of all cells, it can affect various areas of the body, including the brain, eyes, bones, and muscles. Depending on the patient's age at the onset of symptoms, the disease consists of three subtypes: early infantile, late infantile, and juvenile/adult. This condition is considered rare, with most cases having been in the juvenile/adult group of patients.

A Finnish heritage disease is any genetic disease or disorder that is significantly more common in people whose ancestors were ethnic Finns, natives of Finland and Northern Sweden (Meänmaa) and Northwest Russia. There are 36 rare diseases regarded as Finnish heritage diseases. The diseases are not restricted to Finns; they are genetic diseases with far wider distribution in the world, but due to founder effects and genetic isolation they are more common in Finns.

<span class="mw-page-title-main">Northern epilepsy syndrome</span> Medical condition

Northern epilepsy syndrome (NE), or progressive epilepsy with mental retardation (EPMR), is a subtype of neuronal ceroid lipofuscinosis and a rare disease that is regarded as a Finnish heritage disease. Unlike most Finnish heritage diseases, this syndrome has been reported only in Finland. The disease is characterized by seizures in early childhood that progressively get worse until after puberty. Once the onset of seizures occurs, mental degradation is seen. This continues into adulthood, even after seizure frequency has decreased. The cause of the disease is a missense mutation on chromosome 8. The creation of a new protein occurs, and the lipid content of the brain is altered because of it. The ratio of the mutation carriers is 1:135. There is nothing that has been found to stop the progression of the disease, but symptomatic approaches, such as the use of benzodiazepines, have helped control seizures.

<span class="mw-page-title-main">Autosomal recessive cerebellar ataxia type 1</span> Hereditary ataxia that has material basis in autosomal recessive inheritance

Autosomal recessive cerebellar ataxia type 1 (ARCA1) is a condition characterized by progressive problems with movement. Signs and symptoms of the disorder first appear in early to mid-adulthood. People with this condition initially experience impaired speech (dysarthria), problems with coordination and balance (ataxia), or both. They may also have difficulty with movements that involve judging distance or scale (dysmetria). Other features of ARCA1 include abnormal eye movements (nystagmus) and problems following the movements of objects with their eyes. The movement problems are slowly progressive, often resulting in the need for a cane, walker, or wheelchair.

Cerliponase alfa, marketed as Brineura, is an enzyme replacement treatment for Batten disease, a neurodegenerative lysosomal storage disease. Specifically, Cerliponase alfa is meant to slow loss of motor function in symptomatic children over three years old with late infantile neuronal ceroid lipofuscinosis type 2 (CLN2). The disease is also known as tripeptidyl peptidase-1 (TPP1) deficiency, a soluble lysosomal enzyme deficiency. Approved by the United States Food and Drug Administration (FDA) on 27 April 2017, this is the first treatment for a neuronal ceroid lipofuscinosis of its kind, acting to slow disease progression rather than palliatively treat symptoms by giving patients the TPP1 enzyme they are lacking.

References

  1. Pardo, C.; et al. (1994). "Accumulation of the adenosine triphosphate synthase subunit c in the mnd mutant mouse". Am J Pathol. 144 (4): 829–835. PMC   1887237 . PMID   8160780. There are more than eight variants of NCL, found in 1 in 12,500 people worldwide.
  2. 1 2 Wisnewsky, Krystyna E; et al. (2006). "Neuronal Ceroid Lipofuscinoses". GeneReviews (NCBI).
  3. 1 2 Arsov, T; et al. (13 May 2011). "Kufs Disease, the Major Adult Form of Neuronal Ceroid Lipofuscinosis, Caused by Mutations in CLN6". American Journal of Human Genetics. 88 (5): 566–73. doi:10.1016/j.ajhg.2011.04.004. PMC   3146726 . PMID   21549341.
  4. Benitez BA, Alvarado D, Cai Y, Mayo K, Chakraverty S, Norton J, Morris JC, Sands MS, Goate A, et al. (2011). "Exome-sequencing confirms DNAJC5 mutations as cause of Adult Neuronal Ceroid-Lipofuscinosis". PLOS ONE. 6 (11): e26741. Bibcode:2011PLoSO...626741B. doi: 10.1371/journal.pone.0026741 . PMC   3208569 . PMID   22073189.
  5. Noskova L, Stranecky V, Hartmannova H, Pristoupilova A, Baresova V, Ivanek R, Hulkova H, Jahnova H, van der Zee J, et al. (2011). "Mutations in DNAJC5, encoding cysteine-string protein alpha, cause autosomal-dominant adult-onset neuronal ceroid lipofuscinosis". American Journal of Human Genetics. 89 (241–252): 241–52. doi:10.1016/j.ajhg.2011.07.003. PMC   3155175 . PMID   21820099.