Other types of dementia

Mixed dementia

It is characterized by the simultaneity of manifestations of Alzheimer's disease (EA) and vascular dementia (DV). It is estimated that more than a third of patients with AD also have vascular lesions and that a similar proportion of patients with VD have histopathological changes characteristic of AD. The most common presentation of mixed dementia corresponds to atypical clinical features and symptoms of AD, with abrupt worsening and clinical signs of cerebrovascular accident (CVA).

Lewy corpuscle dementia

This disease affects 20% of patients with dementia. It is diagnosed when the cognitive impairment is fluctuating and there are visual hallucinations and extrapyramidal symptoms or similar to those presented in Parkinson's disease. The dementia box has rapid onset and deterioration is progressive, with significant deficits in executive function, problem solving, verbal fluency and audiovisual performance. The most important histopathological findings are Lewy corpuscles - protein inclusions within the cell bodies of neurons found in the cerebral cortex and brainstem - and other types of abnormal accumulations in the central nervous system.

Frontotemporal dementia

The term frontotemporal dementia (FTD) refers to a neuropsychological syndrome characterized by dysfunction of the frontal and temporal lobes commonly associated with the atrophy of these structures and relative preservation of the rest of the brain regions. It is estimated that FTD affects between 10% and 15% of people with degenerative dementia over the age of 40. Patients in the initial stages of the disease present a discrete compromise of the episodic memory, but important cognitive deficits and social and behavioral disturbances. The latter include changes in behavior, disinhibition, mental rigidity and inflexibility, distractions and loss of self-criticism, among other manifestations. The predominant frontal lobe involvement is expressed by behavioral disturbances, disinhibition, apathy, affective dullness, and loss of self-criticism.

Huntington's disease

It is a disease of genetic origin, autosomal dominant, characterized by movement disorders, psychiatric symptoms, and dementia. Dementia becomes evident with the appearance of choreic (heterogeneous movements of the limbs, such as a poorly coordinated dance) and psychiatric symptoms. All aspects of the memory are affected and later arise aphasia, apraxia, agnosia, and global cognitive dysfunction.

Creutzfeldt-Jakob disease

It is the prototype of prion disease in humans. It is a invariably fatal infectious central nervous system disease characterized by dementia rapidly progressive with focal involvement of a region of variable extent of the cerebral cortex and other deeper areas. While it was experimentally shown that it can be transmitted from humans to animals, this appears to be rare among humans. It has been associated with the “mad cow disease”.

Reversible dementias

Normal pressure hydrocephalus

It is a potentially reversible cause of dementia. It is characterized by the triad of dementia, ataxia, and urinary incontinence. It can be idiopathic or secondary to conditions that interfere with the absorption of cerebrospinal fluid, such as meningitis or subarachnoid hemorrhage. It is a type of mild dementia, of insidious onset, which has the characteristic of being preceded by gait disturbances and urinary incontinence. His treatment would be the relief of increased pressure of the cerebrospinal fluid with the placement of a valve.

Pellagra

The cause of this disease is a deficiency of nicotinic acid (niacin or vitamin B3), which affects the neurons of the cerebral cortex, cerebellum and spinal cord. It manifests with diarrhea, swollen tongue, anemia, and skin lesions eczematous. It can cause dementia, psychosis, cerebellar and extrapyramidal signs of involvement, polyneuritis and optic neuritis.

Vitamin B12 deficiency

Vitamin B12 deficiency is a rare cause of reversible dementia and organic psychosis. It is characterized by global cognitive dysfunction, mental slowness, memory loss, and difficulty concentrating. The psychiatric manifestations dominate the clinical spectrum with depression, mania and psychotic pictures with visual and auditory hallucinations. It can be associated with anemia.

hypothyroidism

hypothyroidism causes reversible dementia and chronic psychosis. Dementia is characterized by mental slowness, memory loss, and irritability. The psychiatric manifestations They include depression, paranoia, auditory and visual hallucinations, mania, and suicidal behavior.

Chronic alcoholism

Some complications from alcoholism can cause dementia. These include chronic subdural hematoma from head trauma, hepatocellular degeneration from liver cirrhosis and nutritional deficiencies.

Wernicke-Korsakoff syndrome

This dementia syndrome, which occurs due to thiamine (vitamin B1) deficiency associated with chronic alcohol consumption, is an acute neurological disorder characterized by ataxia (gait and balance disorders), delirium and by the variant of ocular motor disturbances. May progress to chronic amnesic syndrome known as Korsakoff syndrome, in which severe damage to recent memory and learning ability and confabulations is observed, with poor response to vitamin B1 replacement therapy.

Infectious dementias

AIDS-dementia complex

The AIDS-dementia complex is the most common neurological complication of acquired immunodeficiency syndrome. It most frequently affects severely immunocompromised patients in advanced stages of the disease. But nevertheless, may be one of the initial manifestations of AIDS. In general, it is a subacute onset dementia, with apathy, concentration difficulties, memory loss, executive function difficulties and neurocognitive dysfunction.

Neurosyphilis

It was a frequent cause of dementia before the emergence and spread of the use of penicillin in the treatment of the initial stages of the disease. Although it is currently rare, neurosyphilis dementia is part of the differential diagnosis to consider in the face of atypical dementias or with frontal manifestations, particularly in lower income populations.