In no other branch of medicine is a detailed history so important as in neurology, since a properly taken history will enable one to arrive at a reasonable or correct diagnosis and may give some differential diagnosis, which can later be ruled out after physical examination.
The history consists of eliciting the following:
- Name: For identification purposes
- Age: Certain diseases are common in the elderly such as stroke, dementia, tumors, and paraneoplastic syndromes (causes of stroke in the young are dealt with in the Chapter on “Cerebrovascular Diseases”). Certain tumors occur in the young such as craniopharyngioma and medulloblastoma.
- Sex: Stroke is more common in males and has an equal incidence in males and females after menopause due to the protective effect of estrogens and increased high-density lipoprotein (HDL). Male predominance occurs in certain illnesses such as motor neuron disease and female predominance is common in polymyositis.
- Address: To contact the patient in case of reviews and other purposes. Certain diseases are common in certain regions; lathyrism in Madhya Pradesh is due to consumption of lathyrus sativus seeds (grass pea or Indian pea, also called Kesari dal). Fluorosis is common in Punjab, Nalgonda district of Andhra Pradesh, and a small area near Salem in Tamil Nadu and is due to excess fluorine in drinking water causing dental mottling and affection of the spine with compressive myelopathy (fluorine is normally added to drinking water to prevent dental caries).
Kuru, a prion disease or slow virus disease, is common in Papua New Guinea amongst the Fore tribe, who practice cannibalism.
Sleeping sickness is common in eastern and western Africa and Schistosoma haematobium occurs in Egypt and Ratnagiri district of Maharashtra.
Occupation: Quarry workers are more prone to get silicosis which leads to pulmonary tuberculosis and this can spread to the nervous system.
Workers in printing factories are susceptible to lead toxicity which causes encephalopathy and wrist drop.
Workers in glass factories are susceptible to mercury toxicity which can produce involuntary movements, hatter's shakes, and erethism.
Lorry/truck drivers are susceptible to syphilis and infection with human immunodeficiency virus (HIV) which can affect the nervous system much later.2
Occupations that are sedentary predispose to obesity, diabetes mellitus, and hypercholesterolemia leading on to stroke. Exercising is mandatory in such individuals to keep them fit.
Socioeconomic status: The rich and wealthy are more prone to be obese and suffer from diabetes mellitus and hypertension, leading on to stroke, as mentioned earlier.
The poor are malnourished or poorly nourished and suffer from vitamin and mineral deficiencies which can affect the nervous system in various ways.
Educational status of a patient helps in determining his or her general knowledge and abstract thinking, which are part of the higher functions examination. The patient's ability to perform simple calculations, his judgment, memory and orientation to time, place and person are tested in examination of the nervous system.
Handedness: Determines the cerebral hemispheric dominance and language functions that are impaired causing dysphasia (this is dealt with in detail in examination of the nervous system and in disorders of speech). More than 99% of right handed individuals and 75% of left handed individuals have left cerebral hemispheric dominance (centers for speech is on the left side)
Chief/presenting complaints with duration: Only the most important or, at the most three, may be mentioned, the nature of which are elaborated, in the history of present illness.
History of present illness: The complaints, duration, mode of onset, namely acute, subacute, or insidious, precipitating factors, if any, time of occurrence, namely early morning, late evening, night or other times of the day, the part of the body first involved and progression, such as static, worsening, or improving should be mentioned.
Stroke is a sudden catastrophic event due to a vascular episode. It may be due to thrombosis, embolism, or hemorrhage. A person getting up early in the morning, going to the toilet, falling down, as a result of weakness of the limbs, and calling for help usually has a thrombotic event.
A hemorrhagic stroke occurs late in the evening or at night after a hard physical labor or mental strain, in a patient with severe, uncontrolled hypertension. It is associated with loss of consciousness and convulsions. The prognosis depends on the size of the bleed and timely intervention but in general is poorer than the other two.
Embolism can occur at any time of the day, but there should be a source of embolus (such as rheumatic heart disease with thrombus and atrial fibrillation, carotid atheromatous plaque, vegetation in infective endocarditis, paradoxical embolism in congenital cyanotic heart diseases, etc.).
History of transient ischemic attacks (TIAs) are important. They are nonconvulsive neurologic deficits without loss of consciousness that recover completely in 24 hours, but a majority of them recover completely within 1 hour. TIAs are harbingers or forerunners of future stroke due to thrombosis or embolism (the reason for it to be nonconvulsive and not associated with coma is that they are intravascular events in contrast to hemorrhage where blood leaks into the extravascular space).
Any other significant factor such as history suggesting wrist drop, foot drop, claw hand, or carpal tunnel syndrome.
History regarding motor system:
- Power: Graded as per MRC (Medical Research Council, UK) grading (details are in the Chapter on “Examination of the Nervous System”)
- Upper limbs: Ability to lift the arm above the shoulder and combing the hair indicate integrity of the proximal muscles of the upper limb. Proximal weakness is indicative of myopathy. Distal muscle weakness is indicated by inability to write, mix food, and button the garments. Distal 3weakness is indicative of neuropathy. In hemiplegia, both proximal and distal muscles are involved but more of the distal group is affected.
- Lower limbs: Ability to climb up stairs, get up from the chair, and get up from the squatting posture indicate integrity of proximal muscles of the lower limb. Buckling of the knees indicates quadriceps weakness. Ability to grip the footwear (chappals) indicates integrity of the distal muscles of the lower limb. Tripping of the toes while walking also indicates distal muscle involvement. The patient recovering from hemiparesis drags the paralyzed leg while walking in a semicircle (gait of circumduction).
- Muscles of the trunk: Ability to roll on the bed (erector spinae) and ability to get up from the bed
- Neck: Ability to turn the head to one side (opposite sternomastoid), flex the neck sideways toward the shoulder (ipsilateral sternomastoid), and flex the neck to touch the chin (both sternomastoids).Neck is floppy in infantile spinal muscular atrophy or polymyositis.
- Bulk of muscles: Thinning indicates wasting [lower motor neuron (LMN) lesion or disuse atrophy in upper motor neuron (UMN) lesion].Pseudoypertrophy of calf muscles occurs in muscular dystrophy and hypothyroidism.
- Tone: The muscles are stiff like a log of wood (UMN lesion) or flail and flabby (LMN lesions).
- Coordination and cerebellar functions: Inability to bring the food to the mouth without spilling, unsteadiness while walking (ataxia), inability to negotiate narrow pathways, difficulty in reaching a target, and inability to button the garments are features of dysfunction of cerebellum.
- Posterior column: Inability to walk in the dark, unsteadiness, or falling while washing the face (wash basin sign) as the eyes are closed on washing the face with water, a sensation of walking on cotton wool (present also in peripheral neuropathy) are signs of posterior column dysfunction.
- Involuntary movements: Observe for twitching of muscles (fasciculations) and parts of body affected (LMN lesions), whether the occurrence is constant or spasmodic, whether present only at rest, during movement or both, if voluntary movements increase or suppress it, whether there is any alteration with particular position of the trunk or limbs, if it is affected by environment, temperature, or emotion, whether it is altered by eye closure and if it disappears in sleep. All Involuntary Movements Disappear in Sleep Except Myoclonus, which does not disappear or is exaggerated at the onset of sleep (myoclonic startle). Look for violent flinging movements of limbs called hemiballismus which is due to affection of the subthalamic nucleus of Luys.
- Miscellaneous: History of diurnal variation of weakness and fatigability after certain acts like chewing a chapati (chapati test), gazing upward indicates myasthenia. History of occasional episodes of muscle pain, especially in the night, indicates cramps in motor neuron disease.
History of rheumatic fever, vaccination for dog bite or other injuries, drug intake, prolonged vomiting and diarrhea, oral contraceptive intake in females, history of hypertension, diabetes mellitus, and treatment for the same, history of head trauma (which produces subdural hematoma) are to be elicited.
History of hypopigmented patches with loss of sensation is to be elicited (leprosy, when associated with thickened superficial nerves) and so also hyperpigmented patches (café au lait spots) in neurofibromatosis.
Diabetes mellitus produces accelerated atherosclerosis and contributes to stroke (diabetic dyslipidemia). It also causes 4peripheral neuropathy, amyotrophy of anterior thigh muscles, mononeuritis multiplex, autonomic neuropathy, coma (due to hyperosmolar nonketotic state, ketoacidosis, and hypoglycemia), and visual disturbance (diabetic retinopathy). The most common type of peripheral neuropathy in diabetes mellitus is a subacute, symmetrical, slowly ascending sensorimotor polyneuropathy.
Tuberculosis can cause the following in the nervous system:
- Tuberculoma
- Tuberculous meningitis
- Tuberculous endarteritis (inflammation of the endothelium of the arteries) forming a nidus for platelet aggregation and stroke
- Caries spine (Pott's spine)
Hypertension can cause the following in the nervous system:
- Cerebral thrombosis
- Subarachnoid hemorrhage (due to rupture of Berry aneurysms in and around the circle of Willis)
- Intracerebral hemorrhage due to rupture of Charcot Bouchard aneurysms [deposition of hyaline lipid material (lipohyalinosis) thereby weakening the small vessel walls forming aneurysmal dilatation]
- Hypertensive retinopathy
- Malignant hypertension and hypertensive encephalopathy characterized by convulsions and loss of consciousness
- Prolonged vomiting and diarrhea lead to dehydration which predisposes to cerebral venous thrombosis as a result of hyperviscosity
Syphilis leads to the following in the nervous system:
- Tabes dorsalis
- Meningovascular syphilis
- General paralysis of the insane (GPI), producing perioral tremulousness
- Optic atrophy
- Endarteritis resembling tuberculosis
- Gumma
- Erb's syphilitic paraplegia
- Pachymeningitis and meningomyelitis
- Higher functions: Sleep pattern (reversal of sleep rhythm indicates hepatic encephalopathy), fragmented sleep, snoring (history of which is obtained from the spouse) indicates obstructive sleep apnea, speech pattern, delusions, illusions and hallucinations, and lapses in memory (recent memory is always impaired whereas remote is intact) (this is explained in detail in the Chapter on “Examination of the Nervous System”).
- Cranial nerves:
- Ability to smell (olfactory), perverted smell, or parosmia (lesion in temporal lobe)
- See well with appreciation of color (optic) (ask the patient if all quadrants in both eyes are visualized, if he is knowledgeable).
- Diplopia or double vision, ability to see well in all directions, go down the stairs (oculomotor, trochlear, and abducens).
- Able to chew food well and able to feel sensations on the face (trigeminal).
- Drooling of saliva from angle of the mouth (weakness of levator anguli oris), deviation of the angle of the mouth to the sound side, appreciation of taste on anterior two-third of tongue (chorda tympani branch of facial nerve), and hearing loud sounds (paralysis of nerve to stapedius)
- Inability to hear well, ringing sound in ear (tinnitus), dizziness, or vertigo (vestibulocochlear).
- Inability to taste in the posterior part of tongue, which is difficult to judge by the patient (glossopharyngeal)
- Able to turn and flex head, able to shrug the shoulders (spinal accessory)
- Able to mix food inside the mouth and roll the tongue in all directions (hypoglossal nerve)
- Sensory system: Ask whether the patient is able to feel clothes worn around the body, able to feel hot and cold water during bath, has tingling/numbness, feels the ground well or has a sensation of walking on cotton wool, root pains radiating to the toes (sciatica), band-like sensation around the chest or the waist, electric shock-like sensation radiating down the spine on flexion of neck (Lhermitte's sign or barber's chair sign), ability to feel the sensation of water while washing after defecation (in cauda equina lesions, it is lost). Some patients may not be able to feel hot or cold temperature sensation but will feel touch (dissociated sensory loss). History of loss of pain and temperature on one side of face and opposite side of body with no hemiplegia will indicate infarction of lateral wedge of medulla (crossed sensory loss). Loss or impaired sensations, symmetrical in distribution in the extremities, in a glove and stocking manner will indicate peripheral neuropathy.
- Autonomic nervous system: Appreciation of sensation of bladder fullness, initiation of micturition immediately when desired, control micturition once the desire to urinate has occurred, complete evacuation of bladder, feeling of residual urine, history of dribbling of urine, inability to pass urine, history of catheterization have to be asked for. The bladder is palpable per abdomen due to distension in LMN bladder or autonomous bladder and voiding urine at frequent intervals is UMN bladder or automatic bladder. Voiding at inappropriate places and at inappropriate times is indicative of uninhibited bladder (paracentral lobule lesion).
- Normal bowel movement, constipation (myxedema or acute intermittent porphyria), or diarrhea (diabetic gastroparesis)
- Postural giddiness (suggests postural hypotension)
- Lack of sweating or excessive sweating
- Impotency in males: History of nocturnal penile tumescence or passing white or cloudy urine in the morning and history of ability to sustain erection and perform sexual intercourse
- Miscellaneous: History of fever may suggest malaria, meningitis, encephalitis, cerebral abscess, and hyperpyrexia occurs in a pontine bleed, which produces pinpoint pupils due to involvement of the sympathetic chains. History of convulsions, its frequency, duration, and loss of consciousness has to be asked for.
- Consciousness or aware state is due to the integrity of the ascending reticular activating system (ARAS) traveling from lower pons to thalamus on either side and projecting to the cerebral cortex by nonspecific thalamocortical fibers.
- It is lost in hemorrhagic strokes, high-grade hepatic encephalopathy, and cerebral edema in thromboembolic strokes (but in this case convulsions are uncommon compared to hemorrhagic strokes).
- Postictal or Todd's palsy follows focal convulsions and is reversible.
- Past history:
- Similar episodes in the past, fever, head injury, ear discharge, febrile convulsions, tuberculosis, and syphilis
- Personal history:
- Smoking, alcohol consumption, sexual promiscuity, dietary history, and history of breeding pets
- Smoking produces vasospasm and predisposes to coronary and cerebral atherosclerosis and thrombotic or embolic stroke.
- Alcohol produces:
- Acute intoxication in large amounts characterized by ataxia and confusion
- Saturday night palsy by sleeping with the hands hanging over the chair
- Subdural hematoma (SDH) even on trivial falls
- Delirium tremens on alcohol withdrawal
- Wernicke's encephalopathy, characterized by nystagmus, ophthalmoplegia, and confusion
- Korsakoff psychosis, characterized by confabulation
- Cerebellar degeneration
- Rum fits
- Hepatic encephalopathy
- Central pontine myelinolysis
- Marchiafava–Bignami disease in red wine drinkers causing demyelination of corpus callosum characterized by a hemispheric disconnection syndrome
- Alcoholic amyotrophy
- Dietary history:
- Consumption of improperly cooked pork and also raw vegetables, at times, causes cysticercosis and it can affect the nervous system causing seizures.
- Improperly cooked pork consumption also leads to trichinosis which causes paralysis of extraocular muscles and involvement of other muscles as deltoid, biceps, etc., with splinter hemorrhages and eosinophilia.
- Vitamin B12 deficiency can occur in vegans leading to proximal myopathy, subacute combined degeneration of spinal cord, optic atrophy, etc.
- Lathyrism due to consumption of Kesari dal produces spastic paraplegia, due to the toxin β-n-oxalyl amino alanine (BOAA).
- High-fat diet causes hypercholesterolemia predisposing to thrombotic stroke.
- Sexual promiscuity, besides causing neurosyphilis, affects the nervous system also in the form of HIV associated neurocognitive disorders (HAND), dementia, distal sensory neuropathy, myopathy, vacuolar myelopathy, and a variety of diseases due to opportunistic infections such as cryptococcal meningitis, Pneumocystis jirovecii pneumonia (PCP), cytomegalovirus retinitis, toxoplasmosis progressive multifocal leukoencephalopathy, and primary central nervous system (CNS) lymphoma.
- Tropical spastic paraparesis is due to HTLV-1 infection
- Family history:
- Similar illness in the family, birth from a consanguineous union, family history of ischemic heart disease, stroke, or other neurological illnesses such as dementia and muscular dystrophies. An irreversible risk factor for stroke is a family history of stroke.