Tag Archives: Cognitive dysfunction

Subacute Encephalopathies (Rapidly Progressive Dementias)

This is a group of conditions that are collected under the term subacute encephalopathy, which is also called rapidly progressive dementias. These conditions manifest with cognitive dysfunction over weeks or months. Therefore the onset and progression is slower than encephalopathy due to systemic disease and faster than usual causes of dementia which progress over years. … Continue reading Subacute Encephalopathies (Rapidly Progressive Dementias)

Non-vasculitic Autoimmune Inflammatory Meningoencephalitis (NAIM)

Clinical features: Progressive encephalopathy, cognitive impairment. Ataxia, seizures, tremors and visual hallucinations can occur. Findings on investigations: ESR may be raised SS-A or SS-B: may be positive CSF analysis: Often raised WCC and protein Immunoglobulin (Ig)G index and synthesis rate EEG: mild-moderate diffuse slowing MRI: normal Cerebral angiography: normal Pathology, brain biopsy: Leptomeningeal perivascular lymphocytic … Continue reading Non-vasculitic Autoimmune Inflammatory Meningoencephalitis (NAIM)

Niemann-Pick Disease

Diagnosis: A type of lysosomal storage disease Biochemical diagnosis: Fibroblast culture to test for impaired LDL-cholesterol trafficking. Filipin staining: accumulated free cholesterol. Impaired LDL-induced cholesterol ester formation. A variant biochemical form exists Genetics: Autosomal recessive Niemann-Pick disease type C: gene= NPC1 at 18q11 or NPC2 14q Clinical features: Type A: Infantile, severe, cherry red macula, … Continue reading Niemann-Pick Disease

Cerebrotendinous Xanthomatosis

Clinical features: Neonates: cataracts, diarrhea, pyramidal and cerebellar signs, learning disability later on Adults: Seizures, dementia, myelopathy (spinal form), Enlarged tongue, tendon xanthomas, premature vascular disease, cataracts Genetics: Autosomal recessive, CYP27A1 gene on chromosome 2q, sterol 27-hydroxylase deficiency, Findings on investigations: Lipid profile: increased cholesterol CT: white matter hypdensities in cerebrum, cerebellar dentate nucleus hypdensities, … Continue reading Cerebrotendinous Xanthomatosis

Zellweger Syndrome

Synonyms: a.k.a. cerebro-hepato-renal syndrome Diagnosis: A type of Leukodystrophy and peroxisome biogenesis disorders (PBD) Confirmed by Serum very long chain fatty acids: elevated Genetics: PEX3 gene mutations Clinical features: Severe weakness, hypotonia, seizures and developmental delay high forehead, underdeveloped eyebrow ridges, deformed earlobes Hepatomegaly Facial features: high forehead, hypoplastic supraorbital ridges, and midface hypoplasia. A … Continue reading Zellweger Syndrome

Megalencephalic Leukodystrophy with Subcortical Cysts

Diagnosis: A type of leukodystrophy Genetics: MLC1 gene mutation Clinical features: Large head circumference Findings on investigations: MRI: subcortical cysts in the frontal and temporal poles Related articles: White matter diseases, Leukodystrophies,

Vanishing White Matter disease VWM

Synonyms: a.k.a. leukoencephalopathy with vanishing white matter a.k.a. childhood ataxia and cerebral hypomyelination CACH Diagnosis: A type of leukodystrophy. A type of dysmyelination Genetics: Autosomal recessive Mutations in one of five genes for translation factor (eukaryotic initiation factor 2B, elF2B) on chromosome 3: ELF2B1, ELF2B2, ELF2B3, ELF2B4, ELF2B5 Clinical features: <6 year olds at presentation, … Continue reading Vanishing White Matter disease VWM

Canavan Disease

A type of leukodystrophy. A type of dysmyelination. Synonyms: a.k.a. spongiform degeneration a.k.a. N-acetylaspartatoacylase deficiency Genetics: Autosomal recessive. Gene encoding acetylaspartoacylase. Findings on investigations: Imaging: Deep grey matter, subcortical white matter, U fibres, cerebellar, brain stem. Ventriculomegaly/megalencephaly. CT: low density T2 MRI: hyperintense MRS magnetic resonance spectroscopy: Raised NAA Pathology: Vacuolation of white matter. Gliosis. … Continue reading Canavan Disease

Alexander Disease

Diagnosis: A type of leukodystrophy a.k.a. dysmyelination. A type of intermediate filament disease. Genetics: Sporadic. GFAP gene mutation. Encoding Glial fibrillary acidic protein. Findings on investigations: Imaging: Cerebral white matter lesions frontal >occipital. Brain stem atrophy CT: hypodense white matter diffusely. Hyperdense caudate. T1: hypodense white matter. T2: hyperintense white matter Enhancement early in disease … Continue reading Alexander Disease


Synonyms: Leucodystrophy, leukodystrophies Introduction: This is a group of various disorders of abnormal white matter myelination. They are often referred to as dysmyelinating disorders. Types: Adrenoleukodystrophy and adrenomyeloneuropathy Metachromatic leukodystrophy MLD a.k.a. arylsulfatase A deficiency Krabbe disease (Globoid Cell Leukodystrophy) a.k.a. galactocerebroside b-galactosidase deficiency Alexander disease Canavan disease a.k.a. spongiform degeneration a.k.a. N-acetylaspartatoacylase deficiency Sudanophilic … Continue reading Leukodystrophy

Bilateral Striatal Necrosis

Clinical features: Gradual progressive generalised dystonia, choreoathetosis, febrile illness, Genetics: Mitochondrial DNA: ND6 gene, T1487C mutation, Findings on investigations: Respiratory chain analysis: decreased activity of complex 1 Related articles: Mitochondrial disorders,

Leigh’s disease (Subacute necrotizing encephalomyelopathy)

Synonyms: Leigh’s disease a.k.a. Subacute necrotizing encephalomyelopathy Clinical features: 3 months- 2 years of age, poor suck, loss of head control, seizures, cardiac problems Genetics: Mutations in the mitochondrial DNA or deficiencies of pyruvate dehydrogenase Findings on investigations: MRI: symmetric hyperintensity in periaqueductal area, midbrain tectum, caudate, putamen, globus pallidus, substantia nigra. Spares mammillary bodies … Continue reading Leigh’s disease (Subacute necrotizing encephalomyelopathy)

Mitochondrial Neurogastrointestinal Encephalomyopathy MNGIE

Synonyms: a.k.a. MINGE, rare Diagnosis: Genetic analysis Genetics: POLG gene or Thymidine phosphorylase (TP) mutation TP mutation: Autosomal recessive Mitochondrial DNA (mtDNA) analysis: depletion, deletions, and point mutation Clinical features: External ophthalmoplegia, gastrointestinal dysmotility (dysphagia and intestinal pseudoobstruction) and pain, cachexia, peripheral neuropathy, encephalopathy Findings on investigations: MRI: leukoencephalopathy Muscle biopsy: ragged red fibres Treatment: … Continue reading Mitochondrial Neurogastrointestinal Encephalomyopathy MNGIE

General Learning Disability

Synonyms: Formerly mental disability, intellectual disability, a.k.a. mental retardation in some countries Investigations to consider: Vision testing Hearing testing Needs assessment Metabolic tests Genetic testing Tests for neurologic diseases

Leukoencephalopathy (white matter disease)

Damage to white matter may occur due to may conditions that can affect the brain. The clinical features, prognosis and treatment are related to the underlying condition Clinical features: There is a wide range of symptoms: Rapidly progressive dementia/subacute encephalopathy, lower body parkinsonism/gait apraxia, behavioural changes, pseudobulbar speech and pseudobulbar affect may occur Later on … Continue reading Leukoencephalopathy (white matter disease)

Charles Bonnet Syndrome

Diagnosis: This is a clincial diagnosis Clinical features: Vivid visual hallucinations occurring in healthy people with visual impairments e.g. cataracts. Related articles: Approach to cognitive impairment,

Klüver-Bucy syndrome

Diagnosis: This is a clinical diagnosis Clinical features: Hypersexuality, hyperorality, visual agnosia, and placidity (diminished emotional reactions). Investigations to consider: MRI: Lesions in bilateral medial temporal lobes, e.g. Traumatic brain injury, herpes, other infections Consider tests for dementias (FTLD, Alzheimer’s) & infections Related articles: Traumatic brain injury, encephalitis, frontotemporal dementia, Alzheimer disease,

Balint’s Syndrome

Diagnosis: This is a clinical diagnosis Clinical features: Ocular apraxia/ sticky fixation: the inability to move the eyes volitionally Optic ataxia: inability to reach for a target under visual guidance in the absence of primary visual deficits, patients are able to reach under auditory guidance. Simultinagnosia Investigations to consider: MRI: bilateral parietooccipital lesions Consider testing … Continue reading Balint’s Syndrome

Mild Cognitive Impairment (MCI)

Synonyms: a.k.a. Cognitive impairment no dementia CIND: Diagnosis: Clinical examination: Impairment of memory without impairment of functions in activities of daily living ADLs May be amnestic type (amnestic MCI) or non-amnestic Related articles: Approach to cognitive impairment, approach to acute confusion, dementia, Alzheimer’s disease AD, vascular dementia, Frontotemporal dementia FTD,corticobasal degeneration CBD, Progressive supranuclear palsy … Continue reading Mild Cognitive Impairment (MCI)


Diagnosis: Neuropsychological/Psychometric testing Or Clinical features The underlying etiology is determined by a combination of clinical features, neuropsychological testing, imaging and laboratory testing   Clinical features: This is an acquired persistent disorder where there is an impairment of the content of consciousness (intellectual function) with compromise in at least 2, e.g.: Memory Language i.e. aphasia … Continue reading Dementia

Bickerstaff Brainstem Encephalitis (BBE)

Diagnosis: Clinical features plus antibody tests Clinical features: Decreased level of consciousness, areflexia Findings on Investigations: Anti-GQ1b IgG antibody: positive Treatment: Intravenous Immunoglobulin IVIG  

Osmotic Demyelination Syndrome

Synonyms: central pontine myelinolysis, and extrapontine myelinolysis Diagnosis: Clinical features plus MRI plus history of rapid change (increase or decrease) in sodium levels Clinical features: Encephalopathy, coma, quadriparesis, upper motor neuron signs, dysphagia Findings on Investigations: MRI : T2 : high signal in pons, basal ganglia, thalami FLAIR: high signal in pons, basal ganglia, thalami Treatment: Supportive … Continue reading Osmotic Demyelination Syndrome

Organic-Solvent Related Acute Leukoencephalopathy

Diagnosis: Clincial features, exposure to solvent and MRI Clinical features: Solvent exposure Rapidly progressive dementia, akinetic mute, other features Findings on Investigations: MRI: Diffuse symmetric involvement of white matter Pathology: PAS-positive macrophages Electron microscopy EM: membrane-bound lamellar material within macrophage Treatment: Supportive care Related articles: Approach to cognitive impairment, approach to acute confusion, Leukoencephalopathy, Acute … Continue reading Organic-Solvent Related Acute Leukoencephalopathy

Heroin related Acute leukoencephalopathy “chasing the dragon"

Diagnosis: Clinical features plus MRI Clinical features: Initially: Ataxia, dysmetria, and dysarthria, gait abnormalities Later on: akinetic mute, spastic quadraparesis, After recover: tremor Inhalation of vaporised heroin (heroin pyrolysate) “chasing the dragon” Findings on Investigations: MRI: Involvement of white matter (cerebellum, posterior cerebrum, posterior limbs of the internal capsule, splenium of the corpus callosum, medial … Continue reading Heroin related Acute leukoencephalopathy “chasing the dragon"

Hashimoto Encephalopathy

Synonyms: Steroid Responsive Encephalopathy Associated With Autoimmune Thyroiditis SREAT a.k.a. Hashimoto’s encephalopathy Diagnosis: A diagnosis by exclusion with the following: Encephalopathy characterised by: Tremor, transient aphasia, myoclonus, gait ataxia, seizures, and sleep abnormalities +no other identifiable cause +Positive antithyroid antibodies: anti-thyroglobulin or anti-thyroperoxidase antibodies +/-abnormal TFTs: usually hypothyroidism, but may be euthyroid to hyperthyroid +response … Continue reading Hashimoto Encephalopathy

Progressive Multifocal Leukoencephalopathy (PML)

Diagnosis: Clinical and imaging features plus laboratory findings Clinical features: Gradual onset & progressive. Seizures & aphasia may occur Occurs in the setting of immunosupression: e.g. HIV infection/AIDS, immunosupressant medications, Findings on Investigations: JC virus in CSF: by PCR MRI: White matter lesions, usually asymmetric but bilateral, periventricular and subcortical involvement of U fibres, spares … Continue reading Progressive Multifocal Leukoencephalopathy (PML)

Disseminated Necrotizing Leukoencephalopathy (DNL)

Synonyms: a.k.a. Multifocal necrotizing leukoencephalopathy Diagnosis: Clinical +MRI +/-biopsy Occurs after Radiation therapy and/or chemotherapy Clinical features: Encephalopathy Occurs after Radiation therapy and/or chemotherapy Findings on Investigations: CT: White matter, Periventricular, centrum semiovale. Spares the U fibres Hypodensity in white matter. Enhancement can occur. MRI: White matter, Periventricular, centrum semiovale. Spares the U fibres T2 … Continue reading Disseminated Necrotizing Leukoencephalopathy (DNL)

Acute Disseminated Encephalomyelitis (ADEM)

Synonyms: a.k.a. Acute dissemniated leukoencephalitis a.k.a. Acute postinfectious/post-vaccinial perivenous encephalitis, a.k.a. acute demyelinating encephalomyelitis, Diagnosis: Clinical  features plus MRI and supportive tests Clinical features: Encephalopathy, focal findings may occur. Often follows an infectious illness or exposure to new antigen to medication Findings on Investigations: MRI T2: preferred. High signal intensities (large patchy) in white matter … Continue reading Acute Disseminated Encephalomyelitis (ADEM)

Biotin-Responsive Encephalopathy

Diagnosis: Clinical features, laboratory testing and MRI Clinical features: Ophthalmoplegia, nystagmus, ataxia, diplopia and ptosis Complex partial seizures with status epilepticus. Thiamine-responsive Genetics: Thiamine-Transporter Gene Findings on Investigations: MRI: High-intensity signals in the bilateral medial thalamus Laboratory: Thiamine levels: normal Treatment: Thiamine Related articles: Approach to cognitive impairment, approach to acute confusion, approach to diplopia, … Continue reading Biotin-Responsive Encephalopathy

Wernicke Encephalopathy

Diagnosis: Clinical features lone or with MRI findings or low B1 levels +/-Response to thiamine treatment +/-B1 Thiamine: by functional transketolase assay, thiamine chromatography or urinary thiamine Clinical features: Triad: Confusion, ataxia, ophthalmoplegia Not all features are necessary. Occasionally hypothermia occurs. Findings on Investigations: MRI features: Hyperintense signals in the periaqueductal gray area, dorsal medial … Continue reading Wernicke Encephalopathy

Normal Pressure Hydrocephalus

Diagnosis: A combination of clinical features, response to high volume lumbar puncture spinal tap plus imaging Clinical features: Gait disorder, the first symptom: Marche a petis pas: wide-based slow shuffling gait Ignition failure: hesitation on starting to walk Magnetic foot: difficulty lifting foot of the ground Poor postural control Cognitive impairment: Apathy, memory impairment Urinary … Continue reading Normal Pressure Hydrocephalus

Frontotemporal Dementia (FTD)

Synonyms: a.k.a. Frontotemporal lobar dementia FTLD Diagnosis: Clinical features, plus supportive imaging Clinical features: Behavioural symptoms: Progressive change in personality Decline of reasoning Social inappropriateness Primary progressive aphasia: Anomia (inability to retrieve nouns upon demand), Agrammatism (inappropriate word order or use of prepositions), Loss of semantic knowledge about words and objects Clinical variants: progressive nonfluent … Continue reading Frontotemporal Dementia (FTD)

Vascular Parkinsonism

Diagnosis: Clinical features plus supportive MRI and poor response to dopamine agonists Clinical features: Lower body Parkinsonism. Variable cognitive & behavioural deficits. May accompany vascular dementia Findings on Imaging: MRI: multiple subcortical infarcts +/-subcortical leukoaraiosis Treatment: Supportive care Address vascular risk factors Related articles: Approach to movement disorders, Idiopathic Parkinson disease, vascular dementia, ischemic stroke,

Vascular Dementia

Diagnosis: Vascular dementia VaD, NINDS AIREN criteria for probable disease: Dementia +evidence of cerebrovascular disease +a relationship between them Evidence of cerebrovascular disease: Clinical features: Exam showing evidence of previous Also, a triad of: short shuffling gait “marche au petit pas”, pseudobulbar palsy, pseudobulbar affect can occur. MRI (1st choice) or CT: Large vessel disease: Bilateral … Continue reading Vascular Dementia

Transient Global Amnesia

Diagnosis: Clinical features plus supported investigations Clinical features: Acute onset. Lasts 1-24 hours. Complete antrograde amnesia & limited retrograde amnesia (weeks or months). May be disoriented to time, place but not to self. Preserved cognitive functions apart from memory & disorientation No decrease in level of consciousness. Able to interact appropriately during the episode No … Continue reading Transient Global Amnesia


Diagnosis: Clinical features: ataxia, loss of facial motor control, dementia, leg pain Pathology: PRNP gene chr. 20p codon 129 status: MM is a risk factor, Related articles: Approach to cognitive impairment, approach to movement disorders, Sporadic CJD,

Gerstmann–Sträussler–Scheinker Syndrome:

Diagnosis: Clinical features plus imaging Clinical features: 2-10 years, Progressive ataxia & dementia Truncal ataxia, dysesthesia and hyporeflexia of the lower legs, and mild dysarthria Supranuclear gaze palsy Pyramidal signs Pathology: Amyloid plaques: PrP positive Minimal spongiform (vacuolar) change PRNP gene (GSS102) chr. 20p mutation usually Pro102Leu, octapeptide repeats also occur. Findings on Investigations: EEG: … Continue reading Gerstmann–Sträussler–Scheinker Syndrome:

Variant Creudtzfedt-Jakob Disease (vCJD)

Synonyms: New variant CJD, Diagnosis: Clinical +/-EEG +/-MRI +/-CSF findings +/-brain biopsy Clinical features: Abnormal movements (myoclonus, dystonia, chorea), ataxia, slurred speech, tremor, dementia, akinetic mutism Non-specific sensory symptoms Psychiatric symptoms: withdrawal, delusions, depression Findings on Investigations: MRI: Thalamic hyperintensities: bilateral pulvinar (posterior thalamus) a.k.a. ‘Pulvinar sign’. In some there is also bilateral dorsomedial nucleus … Continue reading Variant Creudtzfedt-Jakob Disease (vCJD)

Sporadic Creutzfeldt-Jakob Disease (sCJD)

Diagnosis: A type of transmissible spongiform encephalopathy TSE Clinical +/-EEG +/-MRI +/-CSF findings +/-brain biopsy Clinical features: Rapidly progressive, death usually <1 year Dementia (rapidly progressive), ataxia, myoclonus, rigidity, visual disturbances Focal cortical symptoms (aphasia, neglect, apraxia, acalculia) Akinetic mutism (late feature) Heidenhain variant: Visual symptoms: perception difficulties (colours & structures e.g. metamorphopsia/dysmorphopsia), optical hallucinations, … Continue reading Sporadic Creutzfeldt-Jakob Disease (sCJD)

Epidural Abscess (intracranial or spinal)

Diagnosis: Imaging (MRI with and without contrast) plus biopsy for confirmation Pathology: Biopsy: Necrosis with inflammation (neutrophils & later macrophages & lymphocytes), rim of fibrosis (if absent this is cerebritis) Surrounding gliosis Clinical features: Intracranial: focal neurological deficit Spinal: transverse myelopathy and a flexed posture resisting extension, back pain with fever. Investigations to consider: FBC, … Continue reading Epidural Abscess (intracranial or spinal)

Subacute Sclerosing Panencephalitis (SSPE)

Diagnosis: Clinical features, plus EEG Clinical features: Previous measles infection. Children or young adults. Subacute onset of progressive cognitive deficits, behavioural problems, spasticity, rigidity, Myoclonus, generalised seizures Findings on Investigations: EEG: flat with episodic bursts Anti-measles antibodies CSF: raised IgG index Pathology: Gross: hard brain (gliosis), Microscopic: intracellular (type A) and intracytoplasmic neuronal and glial … Continue reading Subacute Sclerosing Panencephalitis (SSPE)

HIV Associated Neurocognitive Disorders (HAND)

Synonyms: HIV associated dementia HAD, formerly Subacute or Chronic HIV encephalitis a.k.a. AIDS dementia complex formerly AIDS encephalopathy/AIDS encephalitis Diagnosis: Acquired impairment in at least 2 cognitive domains: Learning, information processing speed, attention/concentration +Marked impairment of ADLS +No delirium +No other cause for dementia Other features & tests: Limb incoordination, gait ataxia, abnormal smooth pursuit … Continue reading HIV Associated Neurocognitive Disorders (HAND)

Nonparaneoplastic Autoimmune Limibic Encephalitis

Diagnosis: Clinical features plus antibodies and negative investigations for neoplastic disease Clinical features: Subacute impairment, seizures, temporal lobe seizures & hallucinations, Findings on Investigations: Associated antibodies: VGKC, voltage-gated potassium channels (Kv1) antibodies: These are positive in patients with limbic encephalitis, Morovan’s syndrome. These have differnet targets. Lgi1: leucine-rich, glioma inactivated 1 protein, a subtype of … Continue reading Nonparaneoplastic Autoimmune Limibic Encephalitis

Paraneoplastic Encephalomyelitis, Paraneoplastic Encephalitis

Synonyms: a.k.a. paraneoplastic encephalitis, a.k.a. paraneoplastic limbic encephalits Diagnosis: A combination of serology,  clinical features and identification of underlying tumor Clinical features: Subacute impairment, seizures, temporal lobe seizures & hallucinations, Other features may occur:, Pathology: Limbic encephalitis (medial temporal lobe, hippocampus, amygdala, cingulate gyrus, inula), thalamus, brainstem encephalitis, cerebellum, spinal cord grey matter, dorsal root … Continue reading Paraneoplastic Encephalomyelitis, Paraneoplastic Encephalitis

Fahr disease

Synonyms: a.k.a. idiopathic basal ganglia calcification Diagnosis: A combination of clinical features, imaging and other testing Clinical features: 30-60 y.o. Progressive dystonia, dysphagia, neuropsychiatric symptoms, ataxia Genetics: Autosomal dominant Chr. 14q, Findings on investigations: CT: calcification in the globus pallidus, but also occurs in putamen, caudate, dentate, thalamus and cerebral white matter Serum calcium & … Continue reading Fahr disease


A group of disorders with the following general features Neuroacanthocytosis general features Neurologic symptoms +blood smear with increased acanthocytes (spiky appearing RBCs). Note: wet preparation with a 1:1 dilution with normal saline, i.e. one drop of blood with one drop of saline. Choreoacanthocytosis: Diagnosis: Clinical features: Chorea, orofaciolingual dyskinesia Dysphagia, dysarthria, Seizures Dementia Areflexia (peripheral … Continue reading Neuroacanthocytosis


Diagnosis: Clinical Classification: Grade 1: Transient confusion; no loss of consciousness; concussion symptoms clear in less than 15 minutes. Grade 2: Transient confusion; No loss of consciousness; concussion symptoms or mental status abnormalities last longer than 15 minutes. Grade 3: Any loss of consciousness, either brief (seconds) or prolonged (minutes). Treatment: Return to play (quick … Continue reading Concussion

Subcortical Arteriosclerosis Encephalopathy

Now considered a subtype of Subcortical Vascular Dementia when cognitive dysfunction is present. It is the result of longstanding small vessel disease, particularly due to uncontrolled hypertension. Synonyms: Binswanger disease a.k.a. subcortical arteriosclerosis encephalopathy: Diagnosis: MRI T2/FLAIR: subcortical white matter hyperintensities in confluent areas (initially multifocal), more prominant periventricularly, usually with evidence of previous lacunar … Continue reading Subcortical Arteriosclerosis Encephalopathy

Posterior Reversible Leukoencephalopathy Syndrome PRES

Synonyms: Reversible posterior leukoencephalopathy syndrome RPLS Diagnosis: CT: Hypodensity in affected areas, MRI is better. MRI: T2: Hyperintensity in the occipital and sometimes parietal areas bilaterally. Involves the white matter and sometimes the grey matter. Other affected areas; basal ganglia, cerebellum, brain stem, frontal lobes. Areas usually spared: calcarine cortex, paramedian occipital lobe DWI: hyperintense … Continue reading Posterior Reversible Leukoencephalopathy Syndrome PRES

Posterior Cortical Atrophy

Synonyms: Visual variant of Alzheimer’s disease, Benson’s syndrome   Clinical features: Features of Gerstmann’s syndrome (Alexia, Acalculia, Agraphia, Left-right agnosia/disorientation, Finger agnosia) Features of Balint’s syndrome (simultanagnosia, oculomotor apraxia, optic ataxia), Apperceptive visual agnosia, dressing apraxia, environmental disorientation, hemianopia, transcortical sensory aphasia Less commonly: memory or language disturbances Localises to visual association cortex bilaterally, usually … Continue reading Posterior Cortical Atrophy

Huntington Disease

Genetics: Autosomal dominant HD gene chr. 4p16.3, expansion of CAG trinucleotide repeat. Protein= huntingtin, mutation= expansion of polyglutamine segment. Norma repeat is <26 repeats, Hungtingtons disease if = or >36 repeats Genetic testing for CAG repeat expansion in the huntingin gene Clinical: Chorea, personality change, dementia Chorea: initially as fidgety movements, then it affects fingers, … Continue reading Huntington Disease

Diffuse Lewy Body Disease

Synonyms: Dementia with Lewy bodies, a.k.a. Lewy body dementia a.k.a. Diffuse Lewy body disease DLBD, formerly Lewy body varient of Alzheimers: Clinical features: Dementia: deficits in attention, executive function, visuospatial ability and later on in memory. This is a subcortical dementia i.e. cortical features are spared early in the disease Core features: Dementia that develops … Continue reading Diffuse Lewy Body Disease

Parkinson's Disease

Synonyms: Paralysis agitans: Clinical features: Triad of: Bradykinesia Rigidity. Tremor: this is not essential for the diagnosis Important characteristics: asymmetry, upper body is affected first, fluctuation in severity, postural instability later on BP & postural BP: to exclude Shy-Dragger syndrome Other clinical points: Re-emergent tremor: on testing for postural tremour, initially there is no tremour … Continue reading Parkinson's Disease

Alzheimer Disease

Clinical features: Clinical features in general: Episodic memory loss: This is usually the first symptom  to develop. It preceeds the dysfunction in activities of daily living. In most cases Alzeimer disease develops from amnestic mild cognitive impairment. Later on other cognitive domains are involved this leads to: Executive dysfunction Agnosia Apraxia Aphasia Neuropsychiatric symptoms: depression, … Continue reading Alzheimer Disease