W. Howship Dickinson
1876 The Lancet  
HOSPITAL; SENIOR PHYSICIAN TO THE HOSPITAL FOR SICK CHILDREN. LECTURE III. THE pathology of the lardaceous change was now dis. cussed as of an infiltration beginning with the arteries, and afterwards involving other tissues, of a material the nature of which was a matter of much interest. It had long been known that the material with which lardaceous organs were infiltrated was nitrogenous, and did not differ appreciably in its ultimate composition from fibrine and albumen. The interest chiefly
more » ... he interest chiefly lay in the points of difference between the lardaceous matter and the healthy tissues; one of the most important of these was to be found in the relation of the morbid deposit to the alkalies. The presence of the lardaceous material could be at once detected by its reaction with iodine in a manner to be presently explained. If now the weakest solution of potash or soda, or a stronger one of ammonia, be brought into contact with the infiltrated structure, its power of reacting with iodine was at once and finally abolished, and that without any destruction of the normal tissue, or even material injury to its microscopic structure. This appeared to depend on the extraordinary solubility of the morbid deposit in alkalies, a property which Dr. Marcet toqk advantage of to obtain the material for analysis. Pursuing further the relation of the alkalies to the new material, it was found that infiltrated organs, taking the liver as best suited for the comparison, were deficient in alkali, especially in potash. In a series of healthy livers the total alkaline salts gave an average of 1 0, the potash of '209, in 100 parts. In a series of lardaceous livers the total alkaline salts averaged '739, the potash '169, in 100 parts. While the alkaline salts were diminished under the disease, the salts of the earths were increased. These observations had since been confirmed by some made by Dr. Dupre at the request of the Pathological Society. Comparing the mineral constituents of three healthy livers with three highly lardaceous livers, he found that with the healthy liver the potash amounted on an average to '283 per cent., with the lardaceous to '131 per cent. The chloride of sodium was somewhat increased in the morbid tissue. Passing not? to another organ, it was shown with regard to the spleen that parallel statements might be made. The ash of this organ had been examined in nine instances; three healthy, five lardaceous, and one of rickety enlargement. With the lardaceous change the potash was lessened, as compared to the state of health, from an average of '311 per cent. to one of '196 per cent. The soda varied much, but had apparently su':/fered no loss. The earthy salts were generally increased. With the rickety enlargement, one superficially resembling the lardaceous, though profoundly different from it, diminution was found in the earthy salts only. Reverting to the iodine reaction by which the lardaceous tissue was ordinarily distinguished, it was described as depending on the greater absorption and retention of iodine by the morbid deposit. The supposed amyloid blue had not come within the observation of the lecturer; but the interest which pertained to this reaction, while the deposit was thought to be starchy, no longei existed now that it was known to be nitrogenous. A more obvious interest attached to the remarkable manner in which some of the normal constituents of the body could be made to yield the reaction. This could be done by impart. ing to them acidity. Fibrine under this influence yielded so exact a counterfeit of the lardaceous reaction that he had ventured to call dealkalised fibrine artificial amyloid matter. Fibrine dissolved in dilute hydrochloric acid gave a precipitate with iodine of the characteristic colour, and the same result could be shown on the acidified fibrine as recovered by evaporation. This manifestation of the "amyloid" reaction by certain constituents of the blood on their being transferred from alkaline to acid combination, the paucity of potash in lardaceous organs, and the extreme solubility of the morbid deposit in alkilies, which would seem to prohibit its deposition from blood of normal alkalinity-all these suggest that a deficiency of the alkaline solvent, and a consequent separation from the blood of something for the solution of which the means no longer suffice, is a rude ideal of the morbid process. The causes of the disease were next considered. Reference was made to a series of sixty-six cases, published some years ago, which had led to the inference that the disorder was especially caused by suppuration, independently of any cachectic condition, whether tubercular, cancerous, or syphilitic, with which the discharge might happen to be associated. These conclusions were tested by a tabular analysis of 83 cases fatal in St. George's Hospital since the publication of the previous observations. Of these 60 were connected with ascertained, 4 with presumed suppuration. Cancer existed in 2, tubercle in 37, while there was evidence of syphilis, historical or pathological, in 18. Suppuration was often effective in causing the disease, when of purely local or accidental origin, as in renal stone, ovarian or pelvic inflammation, accident, surgery gangrene or bed-sores. Cachexia might be at once dismissed as not necessary to the production of the lardaceous change. Tubercle and cancer were connected with it only by means of the suppuration they so often caused. Syphilis stood in a different relation to the disorder; it was alone an adequate cause of the lardaceous infiltration, however helped by the discharge due to some of its secondary and tertiary lesions. In the table the disease was attributed to syphilis without excessive suppuration in 11 instances, while evidence or record of syphilis complicated the antecedents of 7 others. -Taking the disease as due to suppuration in the abstract, the modus operandi was taken into question. The infective and exhaustive results of suppuration were considered, and the lardaceous change attributed to the latter. Then as to the essential loss involved in suppuration which occasioned the result, it was inferred that of all the organic constituents of the discharge the white corpuscles were those only which could with any probability be thought to impoverish the system by their removal. The potash of the blood was chiefly contained in its corpuscles, and largely in the white, as evident from the composition of pus.. It was probable, therefore, that suppuration, which essentially consisted in the escape of these corpuscles, might produce its morbid results which were characterised by want of potash by their deficiency. Whatever were the action of the leucocytes, a discharge of pus was virtually a discharge of potash, since pus, chemically speaking, differed from blood mainly in the superabundance of this essential alkali. This loss was apparently the link between suppuration and the lardaceous deposit, and partial impoverishment of the blood and deposition of what was in relative excess presented itself as a rough outline of the process. But besides the exhaustion of discharge, it was clear that there were other modes by which the disorder could be produced. Diminished income was as bad as increased expenditure, and defective assimilation equivalent to increased waste. Under the influence of syphilis we should be prepared to find nutrition impaired in any manner : the attenuation of its subjects showed that their food was not turned to purpose; could it be that the white corpuscles were insufficiently developed and their accompanying potash insufficiently introduced ? 2 -The organic results of the disorder, in relation especially to renal disease, were then considered, with particular reference to the irritative results of the infiltration in the setting up of tubal catarrh and intertubal nucleation, fibrosis and granulation. The occasional presence of arterial and cardiac hypertrophy was regarded as the necessary result of these secondary renal disturbances, though lardaceous infiltration per se had little tendency to cause uraemia, and seldom any result of this nature. No doubt the exhausting dis-_ s
doi:10.1016/s0140-6736(02)49993-x fatcat:mdvkik5zefhafminfpusqejhpe