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Surveying Symptoms and Signs of Neurological Illness

The first stage in the journey of arriving at a correct diagnosis is to be in touch with your symptoms and to convey them accurately to the physicians you see. I recommend arriving to appointments with a written narrative of the temporal progression of symptoms replete with dates and recollections of when certain symptoms emerged and describe how they progressed over time. A savvy physicians will be intrigued and not necessarily put off by a complicated history of the present illness that brought you there.  The history provides a window to the type of ailment, whether of a metabolic, inflammatory autoimmune, genetic, degenerative, or infectious nature, while the physical examination and subsequent testing yields the location within the nervous system where the problem resides. Some symptoms may be unmistakable for a given disorder and yield the answer in short order, while others may be so vague as to straddle several diagnoses or nervous system categories at once.  The categories of neurological disorders can be conveniently divided into those that affect the brain and spinal cord, or central nervous system (CNS) function), or those that affect the peripheral nerves and cause neuropathic disturbances, and others that affect automatic nervous system function lead to dysautonomia. 

CNS disorders are typically uncommon and degenerative but their prototypical features will facilitate a correct diagnosis. Amyotrophic lateral sclerosis, or ALS, better known as Lou Gehrig disease for the baseball player it famously struck, unmistakably involves the brain and spinal cord. It is suggested by the symptom cluster of progressive pharyngeal and limb weakness, wasting and twitching, and spasticity, that results from degenerative loss of upper and lower motor neurons of the brain and spinal cord.  
Multiple sclerosis is recognized by visual loss, facial weakness, vertigo, gait and limb ataxia, incoordination, bowel and bladder incontinence, and sensory symptoms. These result instead from inflammatory demyelinating plaques that disrupt white matter tracts in the brain and spinal cord. 

Parkinsonism lends its name to a the collection of six features, including tremors at rest, rigidity, bradykinesia, loss of balance, flexed posture, and freezing of movement due to a lack of release of ample brain dopamine, a neurotransmitter, which when deficient, leads to decomposition of voluntary movement.  

Herniation of a spinal disc that impinges upon emerging roots is the commonest cause of spinal pain, which while not in the realm of the CNS, can nonetheless impact the spinal cord when seriously compressive. It was described more than a century ago as, the moment at which one feels the crack in [the] back, [which] must have been bent forward, with the lumbar and abdominal muscles in full action such that [they] cause powerful compression of the intervertebral discs, and if that were possible, placing the displacement of the pulp of the intervertebral disc backwards .  
Peripheral nerve system (PNS) disorders are highly variable but predictable from the patient history and physician examination. Guillain-Barre syndrome, abbreviated GBS, causes unmistakable ascending weakness and sensory loss over days resulting in progressive paralysis. Termed acute inflammatory demyelinating polyneuropathy (AIDP), it is preceded by inadvertent viral or bacterial infection that triggers the immune system, resulting in the onslaught of nerve damage. 

There are many different causes of chronic acquired demyelinating neuropathy, but one type termed CIDP, is easily suggested by a careful history, neurological examination and supported by electromyography and nerve conduction studies, abbreviated EMG-NCS, of the limbs.   
Charcot-Marie-Tooth is the name for dominantly- and recessively-inherited weakness that begins in infancy, childhood or early adulthood, and is accompanied by high arches, hammer toes, variable sensory loss, and areflexia. 

Autonomic nervous system (ANS) disorders can lead to deficient vital signs with postural changes, and disturb normal bladder, bowel, and sexual function. They affect individuals of all ages, from childhood to old age.  Postural orthostatic tachycardia syndrome (POTS) and orthostatic hypotension (OH) are ends of a spectrum of ANS disturbances with POTS manifesting palpitations due to an aberrant reflex increase in heart rate leading to palpitations provoked by simple postural changes or mild exertion, and OH manifested by overtly low blood pressure and inadequate compensatory heart rate responses to the same provocations.  The cause may be an infectious or autoimmune trigger, or a breakdown in the hypothalamus-pituitary-adrenal (HPA) axis. Such patients may give an erroneous history of fatigue, mental change, panic attacks, and anxiety suggesting a psychological cause, which ironically worsens with psychotropic therapy due to its neurochemical side effects. 


[1] Middletown GS, Teacher JH. Injury of the spinal cord due to rupture of an intervertebral disc during muscular effort. Glasgow MJ 1911; 76:1-6.