The sympathetic nerve concerns itself with the life of the viscera.  It presides over the visceral economy.

    "A man's power is hedged in by necessity, which, by many experiments, he touches on every side, until he learns its art."
        -- Ralph Waldo Emerson.
 

    We here present the classification of diseases considered to belong to the domain of the sympathetic nerve by various writers.  The classification has no hard or fast lines, but we present it for the purpose of securing a general or bird's-eye view of the field of the sympathetic.  The field of definite action, physiologic, anatomic or pathologic, of the cerebrospinal and sympathetic nerves, is not yet settled.  The pathology of the sympathetic must rest on its physiologic paths.  Physiology, with our present limited anatomical means of tracing nerve fibers, is surer than anatomy.  It is difficult to make a satisfactory classification of diseases of the sympathetic, for a multitude of symptoms, which may reasonably be supposed to depend upon the sympathetic nerves, are encountered without our being able, by minute examination, to recognize the morbid process upon which they depend.  Their chief manifestation is through reflex action, referred disturbance.
    Again, many sympathetic nerves, and especially ganglia, are found at the autopsy sclerosed, pigmented or possessed of increased connective tissue, yet the patient left no records of physical complaints during life.  Hence, it is difficult to retrace, in such cases, the interpretations of Nature's physiologic experiment.  Also, one is not always able to decide whether the pathologic findings at the autopsy are not secondary.  No doubt there is a special pathology of the sympathetic nerve, or rather ganglia; but it may not be a recognized pathology.  In normal and pathological states the sympathetic nerve is constantly affected by reflex irritations.  The pathology of the sympathetic is chiefly observed in the cervical and abdominal ganglia, and is characterized by vascularity, deposit of excessive connective tissue, pigmentation, atrophy, hypertrophy, sclerosis, fatty infiltration, accumulation of microbes and leucocytes in the ganglia, amyloid or fatty degeneration.  Sometimes the blood-vessels of the ganglia are found dilated and engorged with white blood corpuscles.
    Classification of diseases which are certainly, or probably, connected with the sympathetic nervous system:
1.  Functional disturbances:
    (a)  Irritation (hyperesthesia).
    (b)  Paralysis (anesthesia).
2.  Hyperesthesia of the sympathetic (reflex irritation):
    (a)   The abdominal brain (neuralgia celiaca).
    (b)   The mesenteric plexus (enteralgia, enterodynia, colic).
    (c)   Hypogastric plexus (neuralgia hypogastrica).
    (d)   Gastric plexus (gastralgia, gastrodynia).
    (e)   Spermatic or ovarian plexus (ovarian neuralgia).
    (f)   Splenic plexus (splenic neuralgia).
    (g)   Hepatic plexus (hepatic neuralgia).
    (h)   Renal plexus (nephralgia).
    (1)   Pelvic brain or cervico-uterine ganglia (irritable uterus, uterine neuralgia).
    (j)   Aortic plexus.
    (k)   Diaphragmatic plexus.
    (1)   The cervical ganglia.
    (m)   The cardiac ganglia (cardialgia, angina pectoris).
    (n)   Trigeminus (facial neuralgia).
3.  Anesthesia of the sympathetic.
4.  Paralysis or spasmodic affections of voluntary muscles:
    (a)   Locomotor ataxia.
    (b)   Epilepsy.
    (c)   Diphtheritic paralysis.
5.  Progressive muscular atrophy:
    (a)   Pseudo-muscular atrophy.
    (b)   Progressive facial hemiatrophy.
6.  Visceral neuroses:
    (a)   Hysteria.
    (b)   Gastralgia.
    (c)   Gastrodynia.
    (d)   Insomnia.
    (e)   Pleurodynia.
    (f)   Peritonismus.
    (g)  Mastodynia.
7.  Neurasthenia.
8.  Pigmentation:
    (a)   Spleen.
    (b)   Liver.
    (c)   Uterus.
    (d)   Adrenals.
9.  Addison's disease (bronzed skin),
10.  Hemicrania (headache).
11.  Trigeminal neuralgia (facial neuralgia).
12.  Exophthalmic goiter, Pavy's (1825), Graves' (1835), or Basedow's (1840) disease.
13.  Angina pectoris or stenocardia (Heberden's disease (1768).
14.  Diabetes mellitus (hepatic neuralgia).
15.  Diabetes insipidus (renal neuralgia).
16.  Unilateral hyperidrosis (sweating).
17.  Edema.
18.  Diarrhea.
19.  Glaucoma.
20.  Myxedema (sterodema).
21.  Symmetrical gangrene of the extremities.
22.  Pathologic changes in the sympathetic in other diseases:
    (a) In syphilis.
    (b) In old age.
    (c) Leukemia.
    (d) Sunstroke.
    (e) Infectious diseases.
    (f) Cardiac diseases.
    (g) Malignant diseases.
    (h) Pigmentation.
23.  Splanchnoptosia.

    The above table records diseases which are certainly or probably connected with the sympathetic nervous system.  However, some of them are much more doubtfully connected than others.
    We will here consider briefly the hyperesthesias (neuralgias) of the abdominal brain and its closely related plexuses of nerves.  In regard to the functional disturbances, or reflex irritation, we have hyperesthesia or exalted irritability of the sensory nerves.  The hyperesthetic nerve manifests itself first by pain, secondly by a reflex act on a motor apparatus.  Hyperesthesia, or exalted irritability of the sympathetic nerves, is liable to manifest pain irregularity, periodically, paroxysmally, and yet retain some irritability during the intervals.  The symptoms of hyperesthesia are generally uniform and persistent throughout the duration of the disease.  Early life is very free from hyperesthesia of nerves and it does not endanger life.  Anatomically, we know little of the characteristic changes in structure in hyperesthesia.  The etiology of hyperesthesia is obscure; however, malnutrition is perhaps a bottom factor.  The presence of certain substances, such as lead, will induce hyperesthesia or lead colic (neuralgia saturnine).  Climate, sex and age play a role, as does anemia or plethora.  Checking of secretions induces hyperesthesia, as does rheumatism or congestion.  Hyperesthesia generally runs a chronic course, is periodic, is seldom completely recovered from, is often a forerunner of organic disease, is very persistent individually, and is doubtless accompanied by tonic spasm of vessels.
    Hyperesthesia of the nerves of special sense is manifested by phantasms.  One of the objects of this little volume is to attempt to show anatomically and physiologically how reflex irritation in one diseased viscus will unbalance the rest.  For example, what gynecologist has not personally observed that a tender, irritable uterus will unbalance the other viscera (abdominal and thoracic) year after year.  From some form of malnutrition or other morbid process the uterus has become chronically hyperesthetic, and the result is that the secretions and excretions, visceral rhythm and circulation, are disturbed, while malnutrition results with an accompanying neurosis, which is due to the nerve apparatus being bathed in waste-laden blood.
    It is not easy, practical or even useful to discriminate between hyperesthesia and a visceral neurosis, as one may blend into and become identical with the other.  The active hyperesthesias of the great ganglia of the sympathetic system are characterized by an overpowering sense of prostration, a sense of impending dissolution, as if the center of life itself would be destroyed.  This is the essential and common story of neurotic women.  A blow on the pit of the stomach makes one stand with overwhelming awe of a coming danger, a sense of death-like anxiety and annihilation.      These profound impressive sensations are characteristic of the sympathetic nerve.  He who has once fainted need not be told of profound sensations.  It may be stated here that the indefiniteness of the symptoms and findings in the sympathetic tracts have induced theoretical writers to offer placebos to the profession in the form of a profusion of terms, such as gastralgia, gastrodynia, gastric neuroses, and gastric neuralgia, terms some of which mean nothing to the diagnostician, and are confusing to physicians.
    From a careful study of visceral neuralgia it is evident that it is a secondary disease.  It consists of a peculiar malnutrition of a sensitive nerve apparatus.  The treatment of visceral neuralgia consists in improving nutrition, relieving present distress by harmless means and removing all depressing causes.  The cause producing the reflex irritation of different viscera must be discovered and the appropriate remedial agent employed.
 

AN ILLUSTRATION OF THE ABDOMINAL SYMPATHETIC NERVE OF THE MALE       Fig. 2. It is accompanied by ureteral dilatation.       Drawn from a specimen under alcohol which I secured at an autopsy through the courtesy of Dr. W. A. Evans and Dr. C. O' Byrne. 1 and 2, abdominal brain; 10 and 12 represent the spermatic ganglia emitting their plexuses along the spermatic artery; H represents the coalesced hypogastric ganglia. 11, inferior mesenteric ganglia.  Note the network of nerves ensheathing the ureters and also the anastomosis of the plexus spermaticus with the plexus ureteris, hence, the testicular pain is explained in ureteral calculus.  Observe the numerous and marked dimensions of the ganglia renalia.