When, however, the body is subjected to the incidence of injury or disease, great confusion of functions may arise. The constitution may be ruined; the temperament may be profoundly altered, so that it is no longer indicative of healthy physiological action. Under such circumstances, it is convenient to posses's a word that may be used to signify a, mode of action intermediate between physiological processes and the perversion or arrest of such functions when they have been entirely modified by disease. A descriptive term of this character is furnished by the word diathesis. It is in the nutritive functions of the bodily tissues that such deviations from physiologi cal action are most conspicuous. Hence, the proper restriction of the term diathesis to those conditions of nutrition which indicate a radical departure from the normal standard of healthy function without attaining to the manifestation of those strongly marked and intensely morbid types of disease that will overwhelm the constitu tion if the morbid tendency be permitted to advance without check. But the essential nature of a diathesis consists not in a mere reduc tion of constitutional vigor that increases the predisposition to con tract any and every disease that may be incident. It consists in a rearrangement of the structural units of the organism, so that there is established a predisposition to a certain disease or class of diseases. Now, such a rearrangement is an actual departure in a morbid direc tion away from the normal healthy standard of structure. The exist ence of a diathesis is, therefore, the consequence and the expression of disease. When we speak of the gouty diathesis, we speak of a condition of disease in which, though the present manifestations may be insignificant, there is a permanent tendency to greater and greater departures from health that, if unchecked, will finally result in a paroxysmal crisis during which there are critical evacuations that give temporary relief. When we employ the broader term ar thritic we include the notion that there may exist a morbid condition of the body in which, under the influence of various exciting causes, a number of different disorders of nutrition may be induced. But not every disorder of nutrition may be thus excited. Only certain particular maladies can occur under such circumstances. These con stitute the so-called arthritic diseases. There is not yet, however, any uniformity of belief regarding the limits of this class. Some include rheumatism, arthritis deformans, and gout in the same group ; while others believe that rheumatism is an infective disease that possesses only a superficial likeness to gout, and is essentially differ ent in its etiology and pathogeny. Arthritis deformans, also, has been similarly classified and reclassified. Other morbid manifesta tions, such as asthma, bronchitis, interstitial nephritis, cardiac ease, arterial sclerosis, diabetes, lithiasis, and various skin diseases, are so intimately associated with gout, either as antecedents, con comitants, or sequel, that they may justly be reckoned among the evidences of the gouty diathesis, really related to the culminating paroxysms that are known as gout. Hence the accuracy of the state ment that the victim of gout is never thoroughly well. Inherited or acquired, the disease remains permanent, either in the diathetic or the critical form, so long as life endures. This permanence is based upon the radical change in the constitution that has been effected by faulty conditions of living, or has been inherited from a similarly vitiated ancestry. Once established, it is usually unchangeable— incurable. The graver manifestations of the disease may be often warded off by temperance and sobriety; but the less conspicuous outbreaks of the malady can be with difficulty evaded, because they are the expression of the permanent constitutional change that has been effected in the structure of the bodily organism. As Sydenham expressed it, " totem corpus est podagra." Before proceeding to a consideration of the pathogeny of gout, it will be instructive to pass in review the opinions of some of those who have given thought to this subject. Hippocrates and his disci ples taught that gout was caused by an excess of bile and other secre tions that were accumulated by a morbid determination of fluids in the direction of the joints, where they produced deformity, disorgan ization, and painful crises. Galen accepted this doctrine, and added the observation that the disease was not so much dependent upon an alteration of the humors of the body as upon their excessive pro duction. Essentially the same opinions were prevalent during the Middle Ages. Paracelsus and his pupils introduced the hypothesis that the disease was not due to the excessive presence of bile and mucus, but was caused by an inflammation or fermentation within the joints, rendering the synovial fluid acid and corrosive, and causing a deposit of solid matter in and about the diseased structures. Others were of the opinion that the disease was primarily an affection of the blood which precipitated its irritating salts within the articula tions of the extremities. Sydenham accepted the humoral pathology; and, if we translate into modern language the mediaeval terminology which alone was at his command, we shall discover that his doctrines did not widely differ from those that are current at the present time. He believed in the existence of " peccant humors" circulating through out the body as a consequence of "indigestion, or of impaired con coction of matters both in the parts and juices of the body." "At one and the same time the energy of the spirits (nervous energy), which are the instruments of indigestion, is diminished. The viscera are overworked, and thus the spirits, which have been long giving way, are prostrated. If it were not so, if it were a simple weakness of the spirits, children and women and the victims of long illnesses could be equally gouty. On the contrary, however, it is the hearty and robust. These it attacks only during the decline of their best and natural spirits. When this takes place, a congestion of the humors supervenes. From the two together the due concoctions are vitiated and prevented." It is very evident from these extracts that the pathological ideas of this close observer and careful reasoner were not far different from the current opinions of our own time. So long as the digestive organs remain healthy, and the energy of the nervous system continues intact, the precipitation of morbid sub stances from the liquids of the body cannot take place in its joints. Such, in modern phraseology, is the essential teaching of the illus trious Sydenham. These opinions exerted great influence, and were received with few dissenting voices till near the close of the eighteenth century, when, in 1784, Cullen, who was then the leader of English medical thought, announced his adhesion to the view of Stahl, who had declared himself against the humoral pathology of his predeces sors. According to these authors gout was to be considered a disease
of the solid tissues of the body, for there was no evidence of the exist ence of any morbid matters in the blood or other liquids. The articular inflammations originated de novo ; and, as the joints became infiltrated only after long duration and repeated attacks of the disease, the tophi were not causes but merely the consequences of the malady. In the absence of all proof of the existence of morbid matters circu lating in the blood, it was more logical to account for the occurrence of local disorders by supposing that the disease involved all the solids of the body, and that each organ and tissue exhibited its own array of symptoms and morbid changes of structure. Neither could the heredity of gout serve as a proof of the existence of a pathological condition of the liquids of the body, because heredity consists in the transmission of the constitutional peculiarities of the parents to their children, and a " peccaut humor" was certainly not a part of one's constitution. After all it was far more rational to suppose that gout was clue to a perversion of the " energy of the spirits," or ner vous force, mentioned by Sydenhani, rather than to any purely hypothetical change in the circulating fluids of the body. In the absence of any considerable knowledge of physiological chemistry— a branch of science which had then scarcely begun to exist—it was difficult to evade the force of such criticism, and the doctrines of Cullen dominated the minds of men during the earlier years of the nineteenth century. But, with the progress of analytical chemistry, doubts arose. Some of the ablest teachers in France and England expressed the opinion that " lithic" acid was in some way closely connected with the causation of gout. Finally, in 1848, Sir Alfred Garrod furnished the conclusive proof of the presence of uric acid as one of the most essential factors in the etiology of gouty manifesta tions. This brilliant discovery served to re-establish the Immoral theory advocated by Sydenham ; and with but few exceptions the immoral pathology of gout as set forth by Garrod has been generally accepted by the modern school. The lucid simplicity with which Sir Alfred enunciated his theory of gout contributed not a little to its speedy adoption; and the recent experiments of Haig have added lustre to the name of its original expositor.
According to Sir A. Garrod the morbific substance in the blood is the sodium salt of uric acid. This circulates in the blood and lymph, and is deposited in the joints of the gouty subject, where it excites articular inflammation, by which, however, it is destroyed and elimi nated in recent and sthenic cases. But the kidneys, as well as the joints, share in the disease. Hence a progressive, interstitial ne phritis, beginning coincidently with the articular manifestations, or, at least, very closely following them. By reason of this renal disorder, the elimination of mates is hindered, and they accumulate in the tissues—especially in the joints ; whence they are not effectually and completely removed during subsequent attacks. Hence the infiltra tion and disorganization of the articular structures during the ad vanced period of gout. Every cause, therefore, that tends to increase the production and retention of unites acts as a predisposing cause of gout. Reduction of the alkalinity of the blood, diminution of renal activity, and overloading of the tissues with nitrogenous refuse are to be reckoned among the immediately exciting causes of the disease.
In his recent work on "Uric Acid as a Factor in the Causation of Disease" (second edition, 1894) Alexander Haig has more completely elaborated the theory advanced by Sir Alfred Garrod, and has -Edded to it the results of a large number of experimental observations upon his own person, and upon his gouty patients. Being himself a sufferer with uric-acid headaches, he found that by giving up the use of butchers' meat the frequency and the intensity of his headaches were greatly diminished; and that they were again renewed with their original severity after a return to flesh diet. Recognizing the relationship between gout and migraine, he began to investigate the cause of these modifications in the light of gouty pathology. At first he had been, like many others, inclined to believe that such headaches must be due to the formation in the intestines of some poison—perhaps a ptomaine—during the digestion of flesh. But the many points of resemblance between headache and gout served to awaken a suspicion that uric acid might be the exciting cause of migraine as well as of arthritic inflammation. He soon found that the symptoms of headache were invariably connected with the processes by which uric-a' cid compounds are circulated with the blood and are evacuated through the kidneys. During the paroxysm of headache, marked by a slow pulse of high tension, with cold extremities and skin, mental depression and disinclination for exertion of mind or body, the urine is scanty, dense, highly colored, and charged with uric-acid compounds. It is the period when uric acid is circu lating in unusual quantity with the blood, and is being in similar proportion voided with the urine. It is a period of crisis, during which an inordinate surplus of uric acid is discharged from the body. The parallel between the crisis of migraine and that of gout is in this respect very closely drawn. Additional experiments soon revealed the fact that the evacuation of uric acid could be increased by the administration of alkalies, and could be diminished by the similar use of acids. Under the influence of alkalies the pulse would become full, slow, and tense, the urine would be surcharged with uric acid, and headache would be experienced. Giving medicinal doses of an acid would soon reverse the picture, the headache subsiding, and being succeeded by pricking and shooting pains in such joints as had been most actively used before the time of the experiment. The natural inference is to the effect that uric acid, which is now deficient in the blood and urine, must have been precipitated upon the tissues of the painful articulations. Here, then, is an example of an atten uated gout, induced by artificial means—a result that been fre queutly observed by Sir A. Garrod after the use of acid wines and beer. By these interesting experiments it is made apparent that the ingestion of substances which increase the alkalinity of the blood serves to render uric-acid compounds more soluble, and facilitates their evacuation through the kidneys; while the passage of acids into the current of the blood reduces the alkalinity of that fluid so that it cannot hold in solution the urates of the body, and they are conse quently precipitated in solid form among the elements of the tissues, where they excite more or less pain—possibly active inflammation.