Spongif.webporm encephalopathies (prion diseases) are those diseases in which the development of pathological forms of prion proteins is involved. We know more and more about prion diseases, but the key aspects are still unknown - currently medicine does not have the means to cure patients from these diseases.

Spongif.webporm encephalopathiesthat isprion diseasescan develop in the course of life, others arise from inherited, present from birth mutations genes. There are several human entities within this group, examples being Creutzfeldt-Jakob disease or fatal family insomnia.

Prion diseases have been very mysterious for a long time. Unlike other pathogens, such as bacteria, viruses or fungi, they do not contain nucleic acid - prions are made only of proteins. The theory of prion diseases was discovered by S. Prusiner, this discovery was greatly appreciated in the scientific community - in 1997 the researcher was awarded the Nobel Prize in medicine. Although relatively many years have passed since the prion concept was born, some scientists still believe it is incomplete and are investigating further the nature of these conditions - some of the factors responsible for spongif.webporm encephalopathies have now been confirmed.

Prion diseases: causes

The etiology of prion diseases is related to the transformation of normal prion proteins into pathogenic, pathogenic forms. Prions are protein molecules that are found in the body of every human being. Their function is not entirely clear yet, but it is known that under normal conditions, prion proteins do not harm the body. But when prions change their structure and become pathogenic particles, one of several spongif.webporm encephalopathies develops. Prions naturally occurring in the body are referred to as PRPC, while abnormal forms are referred to as PRPSC. The latter are a serious problem not only because they can accumulate in the nervous tissue in the form of deposits and generate its damage, but also because they have the ability to transform normal prions intoincorrect conformation (simply put, PRPSC can "infect" normal proteins with its pathogenic potential).

There are basically 3 causes of spongif.webporm encephalopathies:

  • sporadic (pathogenic mutation occurs in somatic cells, it occurs during the patient's life),
  • family (resulting from the burden of mutations inherited from parents),
  • passaged (related to the introduction of pathogenic prions into the human body, e.g. through growth hormone preparations contaminated with these particles or corneal transplantation from a person suffering from some spongif.webporm encephalopathy).

Spongif.webporm encephalopathies: Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) was first described in the early 1920s. There are 4 types of the disease:

  • sporadic CJD (the most common, accounting for up to 9/10 of all CJD cases)
  • family CJD
  • overwhelmed CJD
  • CJD variant

The clinical picture in the course of various variants of Creutzfeldt-Jakob disease can be variable. The most common ailments in the course of this group of spongif.webporm encephalopathies are:

  • dementia disorders (including progressive deterioration of memory, attention and concentration)
  • myoclonus (involuntary movements like sudden jerks of muscles)
  • cerebellar dysfunction (such as imbalance)
  • visual disturbance
  • pyramidal and extrapyramidal symptoms

In the course of CJD variants, mental disorders (e.g. anxiety, depressed mood), pain and other than the above-mentioned involuntary movements may also appear.

The prognosis for Creutzfeldt-Jakob disease is poor - for example, in patients with sporadic CJD, it takes an average of four to five months from the onset of symptoms to death.

Spongif.webporm encephalopathies: Gerstmann-Straussler-Scheinker syndrome

Gerstmann-Straussler-Scheinker syndrome (GSS) usually runs in families and is caused by an inherited mutation in the PRNP gene. It is considered to be the slowest-progressing spongif.webporm encephalopathy. The GSS team includes :

  • spinocerebellar ataxia
  • dyzartria
  • dementia disorders
  • swallowing disorders
  • nystagmus
  • increased muscle tension

Patients diagnosed with GSS experience a variable amount of time, some patients die more than 10 years after the onset of the disease.

Spongif.webporm encephalopathies:fatal family insomnia

Fatal familial insomnia is a prion disease caused by mutations in the PRNP gene. The disease is extremely rare and has so far been diagnosed in 28 families all over the world. In the course of fatal familial insomnia, the first symptom is inability to sleep. This problem results in anxiety disorders and the patient experiencing hallucinations. The effect of the constant lack of night rest are disturbances in the functioning of the autonomic system (including changes in heart function, sweating and digestive system disorders), there is also a progressive decrease in body weight. In more advanced stages of fatal familial insomnia, hormonal disturbances occur, and symptoms of dementia are present in the course of the disease. The prognosis for fatal familial insomnia, as in other spongif.webporm encephalopathies, is unfavorable: patients usually die within three years of onset.

Spongif.webporm encephalopathies: prionopathy with variable protease susceptibility

The occurrence of the discussed spongif.webporm encephalopathies is mainly related to mutations in the PRNP gene. However, these mutations concern different codons of this gene, therefore several different prion diseases are distinguished. A relatively recently described (in 2008) unit is prionopathy with variable susceptibility to protease. People suffering from this disease are carriers of mutations in as many as three codons of the PRNP gene. In the case of prionopathy with variable sensitivity to protease, patients experience:

  • cognitive impairment
  • extreme severity of psychiatric disorders: they can be euphoria and agitation, but also significant apathy
  • dysartrii
  • aphasia (language disorders)

The average duration of the disease in this prionopathy is less than 4 years.

Spongif.webporm encephalopathies: kuru

Kuru is now considered a disease that practically does not exist anymore - it was encountered in tribes from Papua New Guinea that practiced cannibalistic behavior. The dominant symptom of this spongif.webporm encephalopathy is progressive cerebellar ataxia. It may be accompanied by involuntary movements (mainly in the form of chorea, tremors and athetosis), as well as urinary and faecal incontinence. Patients on kuru also experience significant mood swings, they develop primitive reflexes (e.g. sucking). Quite a characteristic problem in the case of this prion disease are forced bouts of crying or laughing - due to the latter phenomena, kuru is sometimes referred to as "laughing death".

Spongif.webporm encephalopathies:diagnostics

Prion diseases can be suspected on the basis of the patient's symptoms. However, they are quite non-specific, as they can also appear in the course of a number of other diseases that are not related to prions. For this reason, the following are also used in the diagnosis of spongif.webporm encephalopathies:

  • imaging tests (e.g. magnetic resonance imaging, which allows to detect changes related to the degeneration of the brain by prion proteins),
  • laboratory tests (such as the assessment of protein concentrations in the cerebrospinal fluid, e.g. MAP-tau, S-100 or 14-3-3 proteins),
  • genetic tests (allowing to detect the presence of mutations in the patient),
  • immunization tests (using antibodies against prion proteins).

The diagnosis can also be confirmed by autopsy of the brain, in which it is possible to find changes characteristic of spongif.webporm encephalopathies. These can be spongy lesions, variously distributed and with a different structure (depending on a specific disease entity) amyloid plaques and neuronal defects.

Spongif.webporm encephalopathies: treatment

Prion diseases are currently incurable - despite numerous studies that have been going on for many years, medicine still does not have drugs that could slow down or completely inhibit their progress. Symptomatic treatment is used in patients with spongif.webporm encephalopathies to alleviate the intensity of the symptoms and improve their quality of life as much as possible. However, work on treating spongif.webporm encephalopathies is still ongoing. Scientists are trying to use various methods - the first example is gene therapy. They would affect nucleic acids and the mutations present in their structure - the purpose of applying gene therapy would be to neutralize errors in the genetic code. Another approach is the basis of immunological therapy - work is underway to create antibodies whose role would be to eliminate pathogenic prions. Another method where the potential for combating spongif.webporm encephalopathies is seen is treatment with the use of synthesized protein molecules, which - when introduced into the patient's body - would neutralize pathological proteins.

Category:

Neurology