ESSENTIALS OF DIAGNOSIS
Transient or permanent brain dysfunction with alterations in awareness or attention.
Cognitive impairment to varying degrees.
Impaired recall and recent memory, inability to focus attention and problems in perceptual processing, often with psychotic ideation.
Random psychomotor activity such as stereotypy.
Emotional disorders frequently present: depression, anxiety, irritability.
Behavioral disturbances: impulse control, sexual acting-out, attention deficits, aggression, and exhibitionism.
The organic problem may be a primary brain disorder or a secondary manifestation of some general disorder. All of the cognitive disorders show some degree of impaired thinking depending on the site of involvement, the rate of onset and progression, and the duration of the underlying brain lesion. Emotional disturbances (eg, depression) are often present as significant comorbidities. The behavioral disturbances tend to be more common with chronicity, more directly related to the underlying personality or CNS vulnerability to drug side effects, and not necessarily correlated with cognitive dysfunction.
The causes of cognitive disorders are listed in Table 25–8.
Table 25–8.Etiology of delirium and other cognitive disorders (listed in alphabetical order). ||Download (.pdf) Table 25–8. Etiology of delirium and other cognitive disorders (listed in alphabetical order).
|Disorder ||Possible Causes |
|Cardiovascular disorders ||MIs, cardiac arrhythmias, cerebrovascular spasms, hypertensive encephalopathy, hemorrhages, embolisms, and occlusions indirectly cause decreased cognitive function. |
|Collagen-vascular and immunologic disorders ||Autoimmune disorders, including SLE, Sjögren syndrome, and AIDS. |
|Degenerative diseases ||Alzheimer disease, Pick disease, multiple sclerosis, parkinsonism, Huntington chorea, normal pressure hydrocephalus. |
|Endocrine disorders ||Thyrotoxicosis, hypothyroidism, adrenocortical dysfunction (including Addison disease and Cushing syndrome), pheochromocytoma, insulinoma, hypoglycemia, hyperparathyroidism, hypoparathyroidism, panhypopituitarism, diabetic ketoacidosis. |
|Infections ||Septicemia; meningitis and encephalitis due to bacterial, viral, fungal, parasitic, or tuberculous organisms or to CNS syphilis; acute and chronic infections due to the entire range of microbiologic pathogens. |
|Intoxication ||Alcohol, sedatives, bromides, analgesics (eg, pentazocine), psychedelic drugs, stimulants, and household solvents. |
|Long-term effects of alcohol ||Wernicke-Korsakoff syndrome. |
|Medication withdrawal ||Withdrawal from alcohol, sedative-hypnotics, corticosteroids. |
|Medications ||Anticholinergic medications, antidepressants, H2-blocking agents, digoxin, salicylates (long-term use), and a wide variety of other over-the-counter and prescribed medications. |
|Metabolic disturbances ||Fluid and electrolyte disturbances (especially hyponatremia, hypomagnesemia, and hypercalcemia), acid-base disorders, hepatic disease (hepatic encephalopathy), kidney failure, porphyria. |
|Neoplasms ||Primary or metastatic lesions of the CNS, cancer-induced hypercalcemia. |
|Nutritional deficiencies ||Deficiency of vitamin B1 (beriberi), vitamin B12 (pernicious anemia), folic acid, nicotinic acid (pellagra); protein-calorie malnutrition. |
|Respiratory disorders ||Hypoxia, hypercapnia. |
|Seizure disorders ||Ictal, interictal, and postictal dysfunction. |
|Trauma ||Subdural hematoma, subarachnoid hemorrhage, intracerebral bleeding, concussion syndrome. |
The many manifestations include problems with orientation, short or fluctuating attention span, loss of recent memory and recall, impaired judgment, emotional lability, lack of initiative, impaired impulse control, inability to reason through problems, depression (worse in mild to moderate types), confabulation (not limited to alcohol organic brain syndrome), constriction of intellectual functions, ...