Archibaldo Donoso S

Variabilidad y variantesde la enfermedad de Alzheimer

The heterogeneity and variants of Alzheimer disease (AD) are reviewed. There are cases with a slow or fast evolution and with early or late onset. Most cases are sporadic but there are also hereditary forms. About 50% of patients show neuropsychiatric disorders (depression and psychoses). Some cases have a greater deficit of right or left hemispheric functions. Among the variants, there are forms that start as pure aphasias, predominantly prefrontal cases and posterior cortical forms. Occasionally AD may simulate other disorders such as supranuclear palsy, corticobasal ganglionar degeneration and Jacob-Creutzfeldt disease. Finally, there are mixed forms, in which AD is associated with cerebrovascular disease (very commonly) and with other diseases such as dementia with Lewy bodies. We conclude that AD is a heterogeneous disorder and, therefore, clinical diagnosis may be insufficient. Biological markers and specific imaging studies are needed for a correct clinical diagnosis

Demencia frontotemporal: Experiencia clínica

Front temporal dementias (FTD) are neurodegenerative disorders characterized by alterations in behavior, affection and language, with relative sparing of episodic memory. There are three major forms of FTD: the frontal or behavioral form, progressive non-fluent aphasia and semantic dementia (that may begin as a fluent progressive aphasia). Aim: To report a retrospective clinical experience of patients with frontotemporal dementia. Material and methods: Review of 3,700 records of neuropsychological assessments of patients with behavioral disturbances, studied between 1981 and 2008. Of these, 63 patients (59% females) complied with the criteria for frontotemporal dementia. Results: There were 47 cases with the frontal variant, four with non-fluent progressive aphasia and six with fluent progressive aphasias (2 evolved to semantic dementia). The mean age of onset was 60±11 years. There were no familiar cases of FTD. Conclusions: It is clinically difficult to diagnose FTD, since evaluation of attitude or language is required. In addition to structural images, functional images were helpful in some cases, but the definitive diagnosis is anatomical

Demencias frontotemporales: Tres casos de la variante frontal

En la clinica de las demencias frontotemporales, a diferencia de la enfermedad de Mzheimer, destacan las alteraciones de la conducta y del lenguaje y no las fallas de la memoria episodica. Todavia son poco reconocidas en nuestro medio a pesar de ser una de las 3 primeras causas de demencia degenerativa. Se presentan 3 casos seleccionados de una serie clinica: uno con apatia, otro con desinhibicion y el tercero con una conducta estereotipada. Se senalan los aspectos clinicos y los errores diagnosticos cometidos en cada caso.

Anartria o apraxia del habla progresiva

Se presentan dos casos de anartria progresiva, discutiendo la relacion o el diagnostico diferencial con la apraxia del habla progresiva. En ambos casos se trataba de mujeres mayores de 65 anos con un cuadro de perdida progresiva del lenguaje oral, con diparesia facial, lingual y velar, deterioro cognitivo de tipo frontal y discretos signos piramidales. Las imagenes cerebrales estructurales fueron normales. Uno de ellos pudo corresponder a una paralisis supranuclear progresiva, la otra a una degeneracion corticobasal. Se analiza la literatura, llegando a la conclusion de que existen una serie de cuadros que pueden presentarse con un sindrome pseudobulbar progresivo. El diagnostico definitivo debiera ser patologico.

Demencia por déficit de vitamina B12: Caso clínico

Cyanocobalamin (vitamin B12) deficiency can cause polyneuropathy, myelopathy, blindness, confusion, psychosis and dementia. Nonetheless, its deficiency as the sole cause of dementia is infrequent. We report a 59 years old man with a 6 months history of progressive loss of memory, disorientation, apathy, paranoid delusions, gait difficulties with falls, and urinary incontinence. He had suffered a similar episode 3 years before, with a complete remission. On examination there was frontal type dementia with Korsakoff syndrome, a decrease in propioception and ataxic gait. Cerebrospinal fluid examination showed a protein of 0.42 g/L. Brain computed tomography showed sequelae of a frontal left trauma. Brain single photon computed tomography (SPECT) was normal. Complete blood count showed a macrocytic anemia with a hematocrit 29% and a mean corpuscular volume of 117 µ3. Plasma vitamin B12 levels were undetectable, erythrocyte folate levels were 3.9 ng/ml and plasma folate was normal. The myelogram showed megaloblastosis and the gastric biopsy showed atrophic gastritis. Treatment with parenteral B12 vitamin and folic acid reverted the symptoms, with normalization of the neuropsychological tests and reintegration to work (Rev Med Chile 2003; 131: 915-9)

Atrofia cortical posterior

Posterior cortical atrophy (PCA) is a neurodegenerative syndrome, usually due to Alzheimers disease. The first symptoms are progressive impairment of visuo spatial (Balints and Gertsmanns syndromes) or visuo perceptive (visual agnosia, alexia) function. Episodic memory and executive function are spared until later stages. We report two males aged 51 and 55years and three females aged 50, 54 and 56 years, with posterior cortical atrophy. Ophthalmologic study was normal in all. Presenting signs and symptoms were visual ataxia, simultagnosia, agraphia, acalculia, spatial disorientation and unilateral neglect (Balints and Gerstmanns syndromes). Apperceptive visual agnosia, aphasia, apraxia and alexia were also observed. One female had cortical blindness. Structural images were inconclusive, but PET scan and SPECT disclosed functional impairments in occipitotemporal or occipitoparietal areas.

Síndrome de Charles Bonnet: presentación de tres casos y revisión de la literatura

Charles Bonnet syndrome is characterized by the presence ofvisual hallucinations associated with loss of vision. We report three patients aged 74, 84 and 80years (two women) with a severe loss of vision due to ocular diseases and silent visualhallucinations, that they recognized as unreal. Two patients felt that the hallucinations wereominous. Years later, two suffered a probable Alzheimer’s disease (AD). One of them had a mildcognitive impairment when the syndrome appeared, that evolved into an AD with psychosis.This syndrome is not uncommon in older patients with loss of vision and it is probablyunderdiagnosed. Its pathogenesis is probably a cortical deafferentation. The content of thevisual hallucinations (faces, landscaped, and so on) coincides with the activation of differentareas of the visual association cortices) (Rev Med Chile 2007; 135: 1034-39).(

Somatoparafrenia: Presentación de 3 casos

Se presentan 3 casos de somatoparafrenia reunidos en el curso de 30 anos. Se trata de adultos con lesiones vasculares extensas del hemisferio derecho, con hemiplejia, heminanestesia y heminanopsia. Todos tuvieron la conviccion delirante de que su brazo paralizado pertenecia a un familiar proximo. Se senala la variabilidad de los sintomas (somatoparafrenia, personificacion, misoplejia), la relacion de estos con la anosodiaforia mas que con la anosognosia y con lesiones del hemisferio derecho. Se concluye que, a semejanza de los problemas en el reconocimiento de rostros o del entorno, es necesario distinguir entre el nivel de la percepcion y el nivel de la interpretacion como propio o como familiar

Parálisis general sifilítica: presentación de 5 casos

We report five male patients, aged 35 to 63 years who suffered from paretic neurosyphilis. The clinical course was that of a subacute dementia with a frontal syndrome, with more apathy than euphoria. All were HIV negative and four were heterosexual. In all, the cerebrospinal fluid had a mononuclear pleocytosis and a positive VDRL. EEG was abnormal in the 3 cases in whom it was performed. One patient in whom a brain angiography was performed, had images of vasculitis. Treatment with 18-24 million units of penicillin per day during two weeks or more, was partially effective.We report five male patients, aged 35 to 63 years who suffered from paretic neurosyphilis. The clinical course was that of a subacute dementia with a frontal syndrome, with more apathy than euphoria. All were HIV negative and four were heterosexual. In all, the cerebrospinal fluid had a mononuclear pleocytosis and a positive VDRL. EEG was abnormal in the 3 cases in whom it was performed. One patient in whom a brain angiography was performed, had images of vasculitis. Treatment with 18-24 million units of penicillin per day during two weeks or more, was partially effective.

Demencia semántica: Presentación de dos casos y revisión de la literatura

Frontotemporal dementia is a neurodegenerative condition that presents with a number of distinct behavioral phenotypes. One of them is semantic dementia (SD), where exists a profound impairment for semantic knowledge related to atrophy of temporal poles. Pathologically, in most cases positive intraneuronal ubiquitin and tau negative inclusions are observed. SD is characterized by fluent, effortless, grammatical speech which lacks informational content, with limited and repetitive content, as well as semantic paraphasias. Also, patients may present with associative visual agnosia, surface dyslexia or dysgraphia, behavioral alterations. Both episodic and autobiographical memory are close to normality. Two female patients with fluent progressive aphasia are reported; they failed in a simple test of semantic association (to point to one of four objects with lesser relation to others). Autobiographical memory was fair. SD can be wrongly diagnosed as left-sided variant of Alzheimer’s disease; absence of episodic amnesia and parietal defects may be useful for clinical diagnosis.