[Psychiatric manifestations by prions. A narrative review]. / Manifestaciones psiquiátricas por priones. Una revisión narrativa.

Prion diseases are a group of rare and rapidly progressive neurodegenerative conditions that may cause neuropsychiatric symptoms. This group of diseases has been described since the 18(th) century, but they were recognized decades later, when it became clear that the humans were affected by infected animals. There was controversy when the problem was attributed to a single protein with infective capacity. The common pathological process is characterized by the conversion of the normal cellular prion protein into an abnormal form. In humans, the illness has been classified as idiopathic, inherited and acquired through exposure to exogenous material containing abnormal prions. The most prominent neurological manifestation of prion diseases is the emergence of a rapidly progressive dementia, mioclonus associated with cerebellar ataxia and also extra pyramidal symptoms. Psychiatric symptoms occur in early stages of the illness and can contribute to timely diagnosis of this syndrome. Psychiatric symptoms have traditionally been grouped in three categories: affective symptoms, impaired motor function and psychotic symptoms. Such events usually occur during the prodromal period prior to the neurological manifestations and consists in the presence of social isolation, onset of delusions, irritability/aggression, visual hallucinations, anxiety and depression, and less frequent first-rank symptoms among others. Definite diagnosis requires post mortem examination. The possibility that a large number of cases may occur in the next years or that many cases have not been considered with this diagnosis is a fact. In our opinion, psychiatrists should be aware of symptoms of this disease. The main objective of this research consisted of assessing the correlation between this disturbance and neuro-psychiatric symptoms and particularly if this psychiatric manifestations integrate a clinical picture suggestive for the diagnosis of these diseases, but firstly reviewed taxonomic, pathogenic and pathological aspects. The authors of this project also added an element in relation to some diagnostic considerations based on scientific evidence. For the search controlled descriptors applied to the research for indexing scientific articles in databases were used. The electronic data bases used were PubMed, EMBASE and also PsycInfo. The descriptors were prion diseases, psychotic disorders, depression, mood disorders, pathology, classification, prion protein, history, neurological manifestations, and psychiatric manifestations. The selection criteria for the material were qualitative. To conclude, and based on the extensive literature review, the authors propose that the period where the evidence is more robust for mental impaired is named "psychiatric symptoms phase, which can be extended for a few months, being the psychiatric affective symptoms the most characteristic of this phase. In conclusion, we considered that the identification of these symptoms in a patient with risk factors for developing the disease will contribute to the early identification, and would regulate the guidelines in suspected diagnosis of this group of disorders. The intention is provide a better quality of life to the sick people.

Manifestaciones psiquiátricas por priones. Una revisión narrativa / Psychiatric manifestations by prions. A narrative review

Las enfermedades priónicas son un grupo de enfermedades neurodegenerativas raras y rápidamente progresivas que causan síntomas neuropsiquiátricos diversos. Estas enfermedades se describieron hace más de 200 arios, y con el tiempo se reconoció que los animales eran portadores de esta alteración; sin embargo, hasta finales de los noventa este problema conmocionó Europa, ya que para entonces la enfermedad había cruzado la barrera de especie y podía afectar al hombre. La polémica fue mayor al atribuirse la alteración a una proteína con capacidad infecciosa. El proceso patológico común se caracteriza por la conversión de la proteína priónica celular normal (PsPc) a una forma anómala y patológica (PrPSc). En el ser humano se han clasificado como padecimientos idiopáticos, hereditarios o adquiridos por la exposición a material exógeno con contenido priónico. La manifestación neurológica más sobresaliente de las prionopatías consiste en la aparición de una demencia rápidamente progresiva asociada a mioclonías y ataxia cerebelosa, además de síntomas extrapiramidales. Los síntomas psiquiátricos ocurren en etapas tempranas de la enfermedad y su presencia, además de la valoración de factores de riesgo, puede contribuir al diagnóstico oportuno de este síndrome. Clásicamente los síntomas psiquiátricos se han agrupado en tres categorías: síntomas afectivos, alteraciones de la motricidad y síntomas psicóticos. Este tipo de manifestaciones suele aparecer durante un periodo prodrómico previo a los signos neurológicos y consiste en la aparición de aislamiento social, ideas delirantes, irritabilidad/agresión, alucinaciones predominantemente visuales, ansiedad y depresión, así como otros menos frecuentes. El diagnóstico definitivo requiere de un estudio post mortem. La posibilidad de que un número mayor de casos pueda ocurrir en los próximos años o que en muchos pacientes no se haya considerado el diagnóstico es una realidad. En opinión de los autores de este trabajo, los psiquiatras debemos tener conocimiento de los síntomas de esta enfermedad. El objetivo de esta investigación es evaluar las alteraciones neuropsiquiátricas presentes en las prionopatías y, en particular, determinar si las manifestaciones psiquiátricas en conjunto integran un cuadro clínico que apunte al diagnóstico de estas enfermedades, aunque en primer término se revisan aspectos taxonómicos, patogénicos y patológicos. Como elemento agregado en este trabajo, los autores hacen algunas consideraciones diagnósticas basadas en la evidencia científica disponible hasta el momento. Los descriptores controlados aplicados a la búsqueda bibliográfica son los utilizados para indexación de artículos científicos en las bases de datos. Las bases de datos y EMBASE, aunque también se empleó PsycInfo. Los descriptores empleados son: enfermedades priónicas, trastornos psicóticos, depresión, trastornos afectivos, patología, clasificación, proteína priónica, historia, manifestaciones neurológicas y manifestaciones psiquiátricas. Los criterios de selección de material fueron cualitativos. Como conclusión y con base en la extensa bibliografía revisada, los autores plantean que el periodo en que hay más evidencia de alteraciones en la esfera mental se denomine «fase de síntomas psiquiátricos¼, la cual puede extenderse por algunos meses (hasta 4). Los síntomas afectivos son los más característicos de dicha fase. Como conclusiones, se considera que la identificación de estos síntomas en un paciente con factores de riesgo de sufrir esta enfermedad contribuiría a la identificación temprana del padecimiento y normaría qué pautas seguir ante la sospecha del diagnóstico de este grupo de trastornos, sobre todo con la idea de mejorar la calidad de vida de estos pacientes.

Prion diseases are a group of rare and rapidly progressive neurodegenerative conditions that may cause neuropsychiatric symptoms. This group of diseases has been described since the 18th century, but they were recognized decades later, when it became clear that the humans were affected by infected animals. There was controversy when the problem was attributed to a single protein with infective capacity. The common pathological process is characterized by the conversion of the normal cellular prion protein into an abnormal form. In humans, the illness has been classified as idiopathic, inherited and acquired through exposure to exogenous material containing abnormal prions. The most prominent neurological manifestation of prion diseases is the emergence of a rapidly progressive dementia, mioclonus associated with cerebellar ataxia and also extra pyramidal symptoms. Psychiatric symptoms occur in early stages of the illness and can contribute to timely diagnosis of this syndrome. Psychiatric symptoms have traditionally been grouped in three categories: affective symptoms, impaired motor function and psychotic symptoms. Such events usually occur during the prodromal period prior to the neurological manifestations and consists in the presence of social isolation, onset of delusions, irritability/aggression, visual hallucinations, anxiety and depression, and less frequent first-rank symptoms among others. Definite diagnosis requires post mortem examination. The possibility that a large number of cases may occur in the next years or that many cases have not been considered with this diagnosis is a fact. In our opinion, psychiatrists should be aware of symptoms of this disease. The main objective of this research consisted of assessing the correlation between this disturbance and neuro-psychiatric symptoms and particularly if this psychiatric manifestations integrate a clinical picture suggestive for the diagnosis of these diseases, but firstly reviewed taxonomic, pathogenic and pathological aspects. The authors of this project also added an element in relation to some diagnostic considerations based on scientific evidence. For the search controlled descriptors applied to the research for indexing scientific articles in databases were used. The electronic data bases used were PubMed, EMBASE and also PsycInfo. The descriptors were prion diseases, psychotic disorders, depression, mood disorders, pathology, classification, prion protein, history, neurological manifestations, and psychiatric manifestations. The selection criteria for the material were qualitative. To conclude, and based on the extensive literature review, the authors propose that the period where the evidence is more robust for mental impaired is named "psychiatric symptoms phase, which can be extended for a few months, being the psychiatric affective symptoms the most characteristic of this phase. In conclusion, we considered that the identification of these symptoms in a patient with risk factors for developing the disease will contribute to the early identification, and would regulate the guidelines in suspected diagnosis of this group of disorders. The intention is provide a better quality of life to the sick people.