organic mental disorders

DeliriumDementia

Organic Amnestic SyndromeOther Organic Mental Disorders

Organic – due to Primary Brain Pathology

Secondary Brain Dysfunction to Systemic DiseaseSuspicion of organic mental disorder : 1.

First Episode 2. Sudden Onset 3. Older Age at onset 4. Hx of Drug/Alcohol abuse 5. Concurrent medical/neurological problem 6. Neurological signs: Seizures, LOC, Head injury, sensory motor deficit. 7. Presence of Confusion/Disorientation 8. Presence of visual and non auditory (olfactory, gustatory, tactile) hallucinations

A. DELIRIUMA. DELIRIUMCommonest organic mental disorderDefinition: Acute organic brain syndrome

characterized by clouding of consciousness and disorientation develops over a brief period and remits immediately once offending cause is removed.

Epidemiology: - 5 to 15% of medical & surgical px; - High in post op patients; - 40-50% recovering from hip surgery; - Highest rate in post cardiotomy patients; - 30% in ICU

Clinical Features1. Acute2. Clouding of conciousness3. Disorientation (mostly time,

severe cases place and person)4. Short attention

span/distractibility5. Perceptual Distortion6. Disturbance in sleep wake

cycle

DECREASE AWARENESS TO SURROUNDINGDECREASE ABILITY TO RESPOND TO ENVIRONMENTAL STIMULI

ILLUSIONSHALLUCINATIONS Mostly Visual

INSOMNIADAY TIME SLEEPINESS

7. Sun Downing – six in evening8. New Memory Impairement Relatively intact remote memory

9. Speech 10.Mood – Fear, anger rage11.Delusions – Fleeting and fragmentary12.Neuro: Tremors, Dysphasia, Urinary

incontinence

IMPAIRED IMMEDIATE RECALLIMPAIRED RECENT MEMORY

SLURRING of SPEECHINCOHERANCE

Predisposing FactorsOld agePre existing brain damage/dementiaPast history of deliriumAlcohol /drug dependenceChronic Medical illnessSurgical proceduresHistory of Head Injury

Organic ETIOLOGY of DeliriumCLASS ETIOLOGY

METABOLIC Hypoxia, Anemia, Electrolyte disturbance, Hepatic&Uremic Encephalopathy, Cardiac failure,arrest,arrythmia, Hypoglycemia, Metabolic acidosis&alkalosis, Shock

ENDOCRINAL Pituitary, Thyroid, Parathyroid, Adrenal dysfunctions

DRUG/SUBSTANCE

(Many) including alcohol, benzodiazepines, anticholinergics, psychotropics, lithium, AntiHPT, diuretics, anticonvulsant, digoxin, heavy metals, Insulin, salicylates

NUTRITIONAL DEFICIENCIES

Thiamine, Niacine, Pyridoxine, Folic Acid

INFECTIONS (ACUTE/CHRONIC) Septicemia, Pneumonia, Endocarditis, UTI, Meningitis, Encephalitis, Cellulitis

INTRACRANIAL Stroke, Post Ictal, Head Injury, Infections, Migraine, Focal abscess/neoplasms, Hypertensive Encephelopathy

MISCELLANEOUS

Post op, ICU, Sleep deprivation

Management of DeliriumIf cause not known – Do a battery of

investigations : CBC, Urinalysis, Blood glucose, Blood urea serum analysis, Liver and renal function test, arterial p02, Pco2, Thyroid function, B12, Folate levels, CSF, ECG, Drug screen,HIV, EEG, CT & MRI

Correct underlying cause – If underlying cause is found then it must be

treated immediately . For ex50mg of 50% IV dextrose for HYPOGLYCEMIA02 for HYPOXIAIV fluids for electrolyte imbalance

• Drugs given if patient is agitated (most are):– Small dose

BENZODIAZEPINES (Lorazepam, Diazepam)

– ANTIPSYCHOTIC (Haloperidol)

MAINTAIN WITH ORAL HALOPERIDOL, LORAZEPAM TILL RECOVERY IN 1 WEEK

REVIEW DOSE, TAPER AND STOP

DELIRIUM VS DEMENTIA

B. DEMENTIAB. DEMENTIA

• Definition: Chronic Mental Disorder characterized by impairment of intellectual functions, Impairment of memory and deterioration of personality with the course being progressive, stationary or reversible

CLINICAL FEATURESDuration: 6 monthsImpaired Intellectual functionsImpairement of memory (initially mild,

remote memory in later stage)Deterioration of personality with lack of

personal careNo conscious impairmentOrientation-usually normal but falls later

Aphasia – Difficulty in naming an objectHallucinations and Delusions

Additional:-- Emotional lability: Marked variable emotional expression- Catastrophic rxn: When asked to do something beyond her intellectual capibility, she goes into a rage

Types and causes Of DementiaTYPE CAUSES

Parenchymatous Brain Disease

Alzheimers Disease, Parkinson’s disease, Huntingtons’s Chorea, Pick’s Disease, Steel-Richardson syndrome (prog. Supranuclr palsy)

Vascular Dementia

Multiinfarct Dementia, Subcortical Vascular dementia (Binswanger’s disease)

Toxic Dementia

Alcohol, Drugs, Heavy Metals, Bromide, CO, Benzodiazepines, Psychotropics

Metabolic Dementia

Chronic hepatic/uremic encephalopathy, dialysis dementia, Wilson’s disease

Endocrinal Pituitary, Parathyrois, Thyroid, Adrenal dysfunction

Deficiency Dementia

Pernicious anemia, Pellagra, Folic acid, Thiamine deficiency

Infections AIDS, Neurosyphillis, Chronic Meningitis, Creutzfelft-Jacob disease

IOP ↑ Brain tumor, Headinjury hematoma, hydrocephalus Commonest: ALZHEIMERS DEMENTIA, MULTIINFARCT DEMENTIA, HYPOTHYROID DEMENTIA, AIDS DEMENTIA COMPLEX

ALZHEIMER’S DEMENTIAALZHEIMER’S DEMENTIAWomen, Genetic↓ neurotransmitter AcetylCholine due to

degeneration of cholinergic nuclei in basal forebrain

Drugs: Rivastigmine (1.5-6mg/day), Galantamine (4-12mg

BID) -> ↑Ach by slowing its degredationMemantine (5-20mg/day) -> N, Methyl D Aspartate

(NMDA) antagonistVitamin E

MULTI INFARCT DEMENTIAMULTI INFARCT DEMENTIA• Multiple cerebral infarcts causing

dementia due to underlying CVS problem

• Abrupt onset, Acute exacerbations, Step wise clinical deterioration, Fluctuating course

• Focal Neurological signs• Investigations: EEG (focal area of

slowing) CT brain (multiple infarct area)

• Treatment: Underlying (eg HPT)

TIAHPTCVS DISEASEPREVIOUS STROKE

AIDS DEMENTIA COMPLEXAIDS DEMENTIA COMPLEX50-70% patient of AIDSTriad of cognigtive, behavioral, motoric

deficits, -> subcortical dementiaVirus cross BBB -> Cognitive impairementIx ELISA, Western BlotCT may show cortical atrophy

MANAGEMENT OF DEMENTIABasic investigationsTreat underlying cause – mentionedSymptomatic management of anxiety,

depression, Psychotic symptomsEducation – Family, Financial, Support

groupsInstitutionalize in later stage

C. ORGANIC AMNESTIC C. ORGANIC AMNESTIC SYNDROMESYNDROME• Characterized by

– Memory impairment (anterograde, retrograde amnesia) due to an underlying organic cause.

– No impairment of global intellectual function,abstract thinking,personality.

• Caused by Thiamine deficiency in alcohol dependence as part of Wernicke Korsakoff Syndrome

• Any other lesions involving bilaterally the inner core of limbic system(i.e mammillary bodies,fornix,hippocampus, medial temporal lobe,)

The Lesions include: Head traumaSurgical procedureHypoxiaPosterior cerebral artery strokeHerpes simplex encephalitis

Management

Treat the underlying cause if treatable.Ususally treatment is of not much help,except in prevention of further deterioration and the prognosis is poor

D. Other Organic Mental DisordersD. Other Organic Mental DisordersOrganic HallucinosisOrganic Catatonic DisorderOrganic Delusional (Schizo like) disorderOrganic Personality Disorder

Organic Hallucinosis

Etiology:Drugs:Hallucinogens,cocaine,cannabis,bromi

de)Alcohol:In alcoholic hallucinosis,auditory

hallucinations are more commonMigraineEpilepsy: Complex partial seizuresBrain stem lesions

Persistant or recurrent hallucinations due to an underlying organic cause.

No major disruption of consciousness, intelligence or memory

Management 1)Treatment of the underlying cause if

treatable. 2) Symptomatic treatment with a low dose of

an anti-psychotic drug.

Organic Catatonic Disorder

Etiology:Neurologic disorders: limbic encephalitis,Surgical

procedures,sub dural hematoma,cerebral malariaSystemic and metabolic disorders : Diabetic

ketoacidosis , pellagra, SLE, Hepatic encephalopathy

Drugs and poisoning: Organic alkoloids ,aspirin,lithium poisoning ,ethyl alcohol , co

Psychiatric disorders : manic stupor , periodic catatonia , reactive psychosis ,schizophrenia

Management

Treatment of underlying causeSymptomatic treatment with low doses of

benzodiazipam or an anti-psychotic or electro convulsive therapy.

Organic delusional disorderPredominant delusions which are persistant

or recurrent ,caused by an underlying organic cause.

No major disturbance of consciousness,orientation , memory or mood.

Etiology:Drugs:Amphetamines,cannabis,disulfimesSpino cerebellar degeneration Complex partial seizures

ManagementTreatment of underlying causeSymptomatic treatment with low doses of

benzodiazipam or an anti-psychotic or electro convulsive therapy.