Organic Brain Syndromes
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'- -7 " 11.1- -, -;.' .r T '. T. .. ..l-, .-% -,- --, --;. -- John R. Roy Organic Brain Syndromes: Conditions of Acquired Intellectual Deficit SUMMARY The term 'organic brain syndrome' covers a Clinical aspects of acquired mental deficit multitude of ills, many of which are are also outlined. The approach to organic treatable conditions. Diagnosis must brain syndromes is the classic medical concentrate on defining which syndrome is observation of signs and symptoms. (Can involved; this article presents a diagnostic Fam Physician 25:1351-1356, 1979). schema with illustrative case histories. Dr. Roy is director of geriatric duced personality disorders, neuroses adaptive behavior must have their psychiatry services and assistant and psychoses. I neurophysiological substrates which professor of psychiatry at It is not clinically useful to think in can be disturbed by many neurologi- McMaster University. Reprint terms of a unitary, basic 'organic brain cal, metabolic and medical condi- requests to: Room 3G56, Dept. of syndrome'. It is important to be alert tions. Psychiatry, McMaster University to the multifarious psychiatric mani- Though the brain evidently has a Medical Centre, 1200 Main St. W., festations of organic conditions and re- limited repertoire of responses to a Hamilton, ON. L8S 4J9. lentless in search of treatable causes. wide variety of noxious agents, it is Unlike mental retardation, which is important on practical grounds to dis- a condition of arrested or incomplete tinguish between so-called "func- ETABOLIC, TOXIC or infective development of the mind characterized tional" schizophrenia, depression or disturbances of brain cell metab- by subnormality of intelligence, the in- mania and the sometimes very similar olism, as well as brain damage from a tellectual deficit in the organic brain schizophreniform, depressive and variety of causes, are often associated syndromes is acquired at a time when manic syndromes caused by identifi- with disturbed behavior, intellectual the brain has achieved mature develop- able neurologic or medical disorders. deficits, alterations of consciousness ment. The symptomatology therefore These syndromes showing distur- and abnormalities of emotion, thinking comprises loss of intellectual faculties bance of attention, altered level of or perception. previously in existence, together with consciousness, memory disturbance The term organic brain syndrome emotional and other secondary reac- and prominent intellectual impairment given to this constellation of symp- tions to these losses. are more readily recognized as imply- toms is sometimes further subdivided ing a disturbance of brain functioning according to mode of onset and poten- Classification of and thus prompt a search for underly- tial reversibility into acute organic Organic Brain Syndromes ing, potentially treatable coarse brain brain syndrome-otherwise known as It is important not to be clinically pathology or metabolic disease. confusional state or delirium-and handicapped by adopting too narrow a The following case history illus- chronic organic brain syndrome or de- view of organic brain syndromes. trates some of these considerations: mentia. These are both conditions of Many psychiatric disorders could be A woman of 33 was admitted to a global or multiple cognitive impair- termed organic brain syndromes in the psychiatric hospital with a two year ment. There are also syndromes of se- sense that they likely have their causa- history of depression, listlessness and lective or limited disturbance of higher tion in a subtle neurophysiological or undue fatigue. She had formerly been mental function, e. g. the amnestic biochemical disturbance of brain func- a very active, competent person. In the syndrome, as well as organically in- tion. Emotion, thinking, memory and four weeks prior to admission she had CAN. FAM. PHYSICIAN Vol. 25: NOVEMBER 1979 1351 developed an acute psychosis with came afraid to go to sleep and eventu- appropriate studies and she made a marked behavior disturbance. She be- ally left home in a very agitated state. complete recovery on replacement lieved that she heard the neighbors The psychiatric picture was one of thyroid therapy. The psychiatric symp- commenting on her actions and wa- acute paranoid schizophrenia but on toms cleared and showed no recur- kened her husband in the night to in- examination she was noted to have rence at outpatient follow up more form him of her beliefs. This symptom coarse features, brittle hair and her than five years later without the use of of "commentary voices" has been re- mental processes were slowed. An psychotropic medication at any point. garded as one of the pathognomonic electroencephalogram showed a gener- features of schizophrenia. alized slowing of brain wave activity Causes of Later she developed many paranoid in keeping with the presence of a me- Organic Brain Syndromes delusions including one that her hus- tabolic condition. Table I lists various possible causes band was trying to kill her. She be- Hypothyroidism was confirmed by of organic brain syndromes. For clinical use a helpful classifica- TABLE I tion is that of Adams and Victor2 who consider the causes of dementia in CAUSES OF ORGANIC BRAIN SYNDROMES three categories: diseases in which de- mentia is associated with laboratory or Metabolic and nutritional disorders 3. Hydrocephalus: obstructive, clinical evidence of other medical dis- 1. Carbohydrate: functional and communicating ease, e.g. hypothyroidism; diseases in secondary hypoglycemia, diabetic Infections which dementia is associated with pre-coma 1. Meningitis other neurological disease, e.g. 2. Vitamin deficiency: 2. Encephalitis, subacute encephalitis, Schilder's disease or brain tumor, and -Aneurine hydrochloride limbic encephalitis diseases in which dementia is the only (thiamine): Korsakoff's psychosis, 3. Syphilis: general paralysis of the evidence of neurological or medical Wernicke's encephalopathy. insane, meningovascular syphilis diseases e.g. Alzheimer's disease, se- -Nicotinic acid: pellagra 4. Others, e.g. typhoid, cysticercosis, nile dementia. -Vitamin B12: pernicious anemia toxoplasmosis, systemic infections 3. Porphyrins: porphyria The Vocabulary 4. Hormones: Intoxications of Neuropsychiatty -Thyroid: thyrotoxicosis, 1. Exogenous myxedema -Medication: reactions to Precision in definition and use of -Adrenal: Addison's disease, sedatives, stimulants, terms is important,3 since semantics Cushing's syndrome. chemotherapy, hormones, can pervasively influence diagnostic -Pituitary: Simmonds' disease hypotensive drugs, thinking and treatment or placement -Parathyroid: antihistamines, antidepressants, decisions. hyperparathyroidism, bromides. Confusion is often wrongly used to hypoparathyroidism -Self-administered: alcohol, drugs mean disorientation. It really means 5. Oxygen: of addiction perplexity, lack of ability to think -Anesthesia -Occupational: lead, manganese, clearly or incoherence of thought. -Pulmonary disease methyl chloride, carbon disulfide. Confusion as defined thus is not -Renal dialysis. -Poor carrying power, carbon specific to organic mental distur- monoxide poisoning, anemia it can occur as a 6. Malabsorption syndrome 2. Endogenous bances, though result 7. Electrolyte imbalance, alkalosis, Uremia, portal-systemic of impairment of consciousness or acidosis encephalopathy in cirrhosis of liver, brain damage. 'Delirious states' would 8. Copper: Wilson's disease non-metastatic manifestations of be a better term. neoplasms. Clouding of consciousness means a of the level of full conscious- Cerebrovascular disorders Degenerative disorders lowering 1. Cerebral atherosclerosis: 1. Senile dementia ness, alertness or awareness of envi- 'arteriosclerotic dementia' 2. Presenile dementias: Huntington's ronment. This is the characteristic (multi-infarct dementia) symptom that appears when brain 2. chorea, Alzheimer, Pick and Slow cerebral blood flow: cardiac Jakob-Creuzfeldt diseases and function is disturbed by a process of failure, myocardial infarction, recent or rapid (acute) onset. Mild de- postural hypotension, cardiac arrest non-specific types 3. Rarer vascular diseases: 3. Parkinsonism-dementia complex grees of clouding are indicated by dif- polyarteritis nodosa, disseminated 4. Demyelinating disorders: multiple ficulty in maintaining attention, dis- lupus, temporal arteritis, sclerosis, Schilder's disease tractability, slowness of thought, easy thrombo-angiitis obliterans Epilepsy fatigue and subsequent partial or com- 4. Hypertensive encephalopathy Idiopathic and secondary, especially plete amnesia. 5. Carotid occlusion temporal lobe epilepsy. Delirium (acute organic brain syn- 6. Cerebral thrombosis or embolism Psychomotor attacks, petit mal status drome). In delirium, in addition to 7. Transient cerebral ischemia Postictal psychotic episodes (twilight quite marked impairment or clouding states) of there is evidence of dementia and consciousness, Mechanical stresses Epileptic personality widespread disturbance of the brain's 1. Space occupying lesions: primary change and secondary tumor, abscess perceptual and integrative functions, Neuropsychological producing illusions, hallucinations, in- 2. Trauma: acute and chronic brain Depression, psychosis, emotional damage, subdural hematoma, trusion of past mental content into con- disturbance reactive to losses, giving sciousness, delusions and marked post-concussion syndrome, up, stress. punch-drunk syndrome emotional and behavioral disturbance 1 352 CAN. FAM. PHYSICIAN