Nondegenerative Dementias and Encephalopathies

Nondegenerative dementias are a diverse but important group of cognitive disorders because they may be reversible with treatment. Thus, evaluation is important when a nondegenerative dementia is suspected. Many causes of nondegenerative dementia result in what is known as subcortical dementia, which is thought to be primarily due to damage to the frontal subcortical connections. Typical clinical features include inattention, bradyphrenia (slowed thought process), executive dysfunction (difficulties planning and sequencing tasks), apathy, psychomotor slowing, and mood disorders. Gait apraxia and urinary difficulties may coexist. Cortical features such as agnosia, seizures, aphasia, and ideomotor apraxia are typically absent.

Neurologic Associations With Cardiac, Pulmonary, Renal, Hepatobiliary, and Hematologic Disease

The brain has a higher demand for cardiac output than any other organ, and it strictly relies on oxygen and glucose metabolism. Consequently, the brain is exquisitely sensitive to homeostatic disturbances and extraneural organ dysfunction leading to cardiac, pulmonary, renal, hepatobiliary, and hematologic diseases. The primary neurologic manifestation of extraneural organic dysfunction is diffuse bihemispheric dysfunction or encephalopathy, which often lacks lateralizing or localizing signs. Common clinical findings are lethargy, difficulty with attention and orientation, sleep-wake disturbance, and psychomotor slowing. As organic dysfunction progresses, a moderate encephalopathy ensues, with worsening cognitive function, gross disorientation, hypoactive or hyperactive psychomotor state, frontal release signs, asterixis, and myoclonus. If organ failure (eg, hepatic or renal) progresses further, stupor and coma may result unless organ function improves. Patients with underlying organic brain disease from degenerative dementia can decompensate out of proportion to neurologically normal counterparts, resulting in encephalopathy even from minor organ dysfunction or infection.

505 - Reversible Dementia caused by Hypothyroidism – a case report

OBJECTIVES:Reversible causes are thought to explain about eight percent of all dementias. Hypothyroidism is one of the most important causes of potentially reversible dementia. Deficits in memory, psychomotor slowing, general intelligence, and visuoperceptual skills are particularly involved and may not fully recover. We review a clinical case of a reversible dementia caused by hypothyroidism, in a patientfollowed in our institution.METHODS:Case report using clinical files, and brief literature review using Pubmed database, searching for the keywords “reversible dementia”, “hypothyroidism” and“psychosis”.RESULTS:We present a case of a 76-year-old female patient admitted in our acute unitwith visual and auditive hallucinations and persecutory delusional ideation for 1 month. There was no previous psychiatric history. The patient was fully oriented in space, time and person, but there were clear memory deficits and sensitivity to antipsychotics. We used the Montreal Cognitive Assessment (MoCA) and the Frontal Assessment Battery (FAB), having the patient scored 17 on the former and 3 on the latter, failing in all tests except for grasping. On the blood tests, fT3 and fT4 levels werenear 0 and TSH was 40 µg/dL. We then discovered that the patient had a thyroidectomy 25 years ago and had been doing replacement treatment since then buthad discontinuated treatment on the previous six months. We also did magnetic resonance imaging that showed frontal microcirculatory changes but without clear atrophy. The patient was treated with aripiprazole 30mg and levothyroxine 0,150mg, being discharged after 1 month, without psychotic symptoms. About 1 year after, we repeated MoCa and FAB, scoring 27 and 16, respectively. The psychotic symptoms didn’t recur even after the antipsychotic discontinuation.CONCLUSION:We present a case of hypothyroidism induced dementia with psychotic symptoms, that fully recovered with thyroid replacement treatment, without previous neurological or psychiatric history.

Fulminating Autoimmune Demyelination with Optic Neuropathy in a Case of Pediatric Cerebral Adrenoleukodystrophy: Case Report and Review of the Literature

X-linked adrenoleukodystrophy (ALD) is a leukodystrophy characterized not only by progressive loss of myelin in the central nervous system due to dysmyelination, but also by acute, subacute, or chronic inflammatory demyelination. This results in the phenotypic variability of cerebral ALD (cerALD), which is independent of the genotype. In this manuscript, we report a fulminant presentation with fluctuating encephalopathy and visual loss in a patient with childhood onset cerALD. Brain MRI showed symmetric confluent occipito-temporal demyelination with severe disruption of the blood–brain barrier and prechiasmal optic neuropathy. The patient's cerebral spinal fluid (CSF) demonstrated an elevated IgG index, myelin basic proteins, and oligoclonal bands. Within 48 hours of receiving immunomodulating therapy, the patient's symptoms of psychomotor slowing, visual impairment, and areflexia partially resolved. High plasma C26:0 levels and high ratios of C24/22 and C26/22 were diagnostic of ALD. It has been shown that environmental factors play an important role in the inflammatory demyelination responsible for the severe phenotypes of cerALD.

Creutzfeldt-Jakob disease Heidenhain variant: case report with progressive cognitive decline recorded by videos

Context: Creutzfeldt-Jakob disease (CJD) is a rapidly progressive neurodegenerative disease. Heidenhain’s variant has isolated visual symptoms that persist even without any cognitive decline for a few weeks. Objective: To report a case of the Heidenhain variant of the CJD with evolution documented. Methods: Case report:A 67-year-old woman was admitted to the emergency room with a report of “seizures and dementia for 1 month”. It all started in August 2020 with a decrease in visual acuity. The son started to record the evolution of the disease in vídeos on his mobile phone. It got worse, with an inability to reach objects and optical apraxia,psychomotor slowing, abnormal repetition of acts and impairment of judgment. MRI of the brain (normal) and EEG was performed, with diffuse slowing of the base activity. It evolved with intermittent myoclonus and abulia. Extensive investigation for encephalitis: normal. Treatment with acyclovir and pulsetherapy with methylprednisolone were performed. Results: new brain MRI: restricted area following the diffusion and T2 / FLAIR hypersignal exclusively cortical involving both posterior hemispheres. Also new EEG: generalized periodic discharges. The 14-3-3 protein was detected in her CSF.The patient died 4 months after the onset of the condition due to infectious complications. Conclusions: The Heidenhain variant of CJD should be considered a differential diagnosis in all patients who have isolated visual complaints, especially if associated with cognitive complaints. The video recording of the patient allows a detailed analysis of the clinical picture and becomes an important diagnostic complementation tool.

Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

Objective: Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenenace and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task.Methods: 41 depressed participants and 41 age- and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz). Results: MDD participants had prolonged response times and more positive P3 amplitudes relative to controls. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty.Conclusions: Depression is associated with generalized psychomotor slowing of working memory processes, as well as compensatory hyperactivity in frontal regions.Significance: These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable workig memory performance to controls.

319 - Challenges in the diagnosis and treatment of dementia in schizophrenic patients: on the behalf of a clinical case

Studies have been showing that schizophrenia is significantly associated with the risk of all-cause dementia. The neurobiological mechanisms underlying this association are not clarified, as well as, the role of antipsychotics mediating the risk of dementia.The main aim of this work is, through the presentation of a clinical case, to show the evolution from symptoms of schizophrenia to dementia. The second aim is to present the challenges in the diagnosis and management of dementia in schizophrenic patients.Along with the description of the clinical case we present a brief summary of a Pubmed search with the Mesh terms “schizophrenia” and “risk” and “dementia”. We selected clinical trials and review articles published in the last 5 years. From a total of 132 articles, we selected those who matched better our aims.The patient is a 66-year-old man with a diagnosis of schizophrenia since the age of 40. In 2017 he began to develop episodes of temporal and spatial disorientation, followed by difficulties in naming and eventually functional impairment for daily activities. The initial mini mental test quoted 26/30, halving in less than two years.The lumbar puncture revealed a Tau/Amyloid beta42 ratio compatible with Alzheimer dementia. Since language was clearly the first domain affected, it was diagnosed a logopenic variant of Alzheimer dementia.We associated to the antipsychotic treatment galantamine 10mg and then raised it to 16mg. The loss of language was progressive, and the patient started to show psychomotor slowing and abnormal gait. We reduced paliperidone from 75mg/ml 50mg/ml but after two years of functional deterioration and apathy we eventually stopped the antipsychotic.In the last six months the patient has been stable with galantamine 16mg, memantine 20mg, although dependent for daily activities.Whether schizophrenia independently increases dementia incidence, or whether this correlation is confounded by traditional dementia predispositions (cerebrovascular disease, substance abuse and others) is unclear as studies have shown inconsistent results. On the other side, the cumulative use of antipsychotics for schizophrenia patients was related to cognitive decline in an observational follow-up study.Further studies should explore whether treating schizophrenia is a potentially modifiable risk factor for dementia.