PATHOLOGY.—The essential character of scurvy consists in perverted nutrition, in which the blood undergoes such peculiar and profound changes that its fitness for the maintenance and renewal of the various tissues and organs is impaired; hence the nervous depression, loss of muscular power and tonicity of tissues, and the transudation of the blood or of its constituent parts.
The processes of secondary assimilation are chiefly at fault, leading to the blood-changes, and through these to the textural lesions. Primary assimilation remains intact, as the bodily weight is little altered as long as the food is in sufficient quantity. This loss of nutritive balance between the blood and tissue is due to the absence of certain elements furnished by fresh vegetable matter. What these are, and how their absence acts in inducing this disturbance, have not yet been determined; we only know that the mysterious harmony of the vital, chemical, and physical relations which exist between the blood and tissues in health is deranged by their absence.
Endless explanatory surmises and assumptions have been proffered. The earlier explanations involve either the Galenical theory of putrefaction of the fluids and humors, a breaking down of the blood-corpuscles, or the later chemical theories of superabundance or absence of certain salts, sulphur, etc., and hence there were an acid scurvy, an alkaline scurvy, a muriatic scurvy, etc.
The frequent effusions of blood in scurvy led Andral to suspect that the chief peculiarity in scorbutic blood was the decrease of fibrin; which was in perfect accord with a theory that he had formed that this change was the uniform cause of passive hemorrhage. Magendie had already given experimental support to this conjecture by inducing in animals phenomena analogous to those of scurvy by the injection into the veins of defibrinated blood or of alkaline solutions. Andral7 believed his views confirmed when in 1841 he analyzed on two occasions the blood of scorbutic patients and found the fibrin reduced to 1.6 parts per 1000. Similar results were obtained by Eckstein and Frémy. On the other hand, the blood was analyzed by Busk, about the same time, in three well-marked cases of scurvy that occurred on the Dreadnaught hospital-ship, and in all of them the fibrin was in excess of the normal amount, the least being 4.5 and the greatest 6.5 parts per 1000. In perfect accord with Busk's results were the analyses of the blood of five scorbutic females, communicated in a note to the Academy of Sciences in 1847 by Becquerel and Rodier. In no case was the fibrin diminished, but in some it was sensibly increased. In a subsequent case Andral found that the fibrin, instead of being less, exceeded the physiological mean, reaching 4.4 parts, and he concluded that a diminution of this element was not a necessary and common occurrence, but only an effect—a result of prior morbid modifications, and a consequence which was produced more or less frequently according to the severity and duration of the disease. Parmentier and Déyeux found the blood of three scorbutics to resemble inflammatory blood in respect to fibrin, while Frick obtained in one analysis 7.6 parts of fibrin and Leven 4.3 parts.
7 Essai d'hématologie pathologique.
In mild cases of scurvy neither the color, the alkalinity, nor the coagulability of the blood differs from that of blood in health, though Wood alleges that the clot is loose and cotton-like, and Canstatt that its coagulability, in consequence of the large proportion of saline matters, is diminished. In Busk's cases the separation of the clot and serum was as perfect, and took place as rapidly, as in healthy blood, and in two of them the blood was both buffed and cupped, as it was also in Leven's cases. In two of the most severe of Becquerel's cases the blood coagulated firmly, and in a slight case the clot was dark and loose. The albumen of the blood shows no marked change as regards its quantity. The five analyses of Becquerel and Rodier showed the average amount of organic matters of the serum to be 64.3 parts in 1000, the smallest being 56.2 and the largest 69.2 parts. 1000 parts of the serum of the same cases gave an average of 72.1 parts of organic matter. Frick's single case gave 87.045 parts per 1000, and the average of Busk's was 78.2 parts, while Chotin and Bouvier obtained only 62.3 parts. The last-mentioned writers have recorded a fact in connection with the physical characters of scorbutic blood that deserves notice: the blood in one case did not coagulate at the usual temperature (about 158° F.), but required a temperature some degrees higher for that purpose. The red corpuscles in all the foregoing cases were notably diminished, the largest amount given being 117.078 parts per 1000, while the lowest was 47.8 parts. In Andral's second case the globules had decreased to 44.4 parts per 1000, the lowest amount yet recorded.
The alkalinity of the blood seems not to be changed, although Chotin and Bouvier noticed a slight increase. The saline constituents do not vary greatly from the normal standard. The average amount in the cases of Becquerel and Rodier and Busk was 8.1 per 1000, the smallest being 5.5 parts and the largest 11.5. In Ritchie's two analyses the proportion of saline matters is given as 6.44 and 6.82 parts per 1000. Opitz and Schneider have found less than the physiological mean. In Frick's case the amount was 8.8, the iron being 0.721 parts per 1000, and 0.782 to 127 parts of globules; lime 0.110, chlorides 6.846, and phosphates 1.116 parts per 1000. The iron was in excess of that in the normal blood, but in Becquerel's cases the mean was 0.381—less than the normal. The proportion of iron in Duchet's cases was respectively 0.393, 0.402, and 0.476 parts, giving a mean of 0.423 parts per 1000, which nearly approximates the normal. Garrod in one analysis of the blood found a deficiency of the potassium salts, upon which he erected his well-known theory of the etiology of the disease. It is an interesting fact that in the physiological state the quantity of sodium chloride is not subject to variation, any excess introduced with the food being thrown off by the kidneys. The quantity in the urine bears a relation to the amount introduced as food, but the proportion in the blood is constant.
The quantity of water in the blood has been found to be increased in all the analyses which have been made. Chotin and Bouvier estimated water and loss at 831.1; in Frick's case it was 791.69 parts per 1000; and in Becquerel's five cases it was put at 807.7, 810.9, 811, 813.7, and 854.0 parts per 1000, respectively. In Busk's three cases the lowest amount was 835.9 and the highest 849.9 parts per 1000. The specific gravity of the defibrinated blood was in all cases low in comparison with the normal standard (1057), the average in Becquerel and Rodier's cases being 1047.2, the lowest 1083.3, and the highest 1051.7. In the single observation of Chotin and Bouvier it was 1060. The specific gravity of the serum was also less than normal (1027), the average of four of Becquerel's analyses giving 1023.8, the lowest 1020.8, and the highest 1025.5. Busk gives 1025 in one case and 1028 in another.
The results of the most recent analyses, those of Chalvet, are shown in the following table, in which scorbutic blood is contrasted with that of a healthy, robust female:
| Scorbutic blood. | Healthy blood. | |
| Water | 848.492 | 772.225 |
| Solid matters | 151.508 | 220.775 |
| Dry clot | 140.194 | 209.000 |
| Albumen | 72.304 | 68.717 |
| Fibrin | 4.342 | 2.162 |
| Globules | 63.548 | 138.121 |
| Extractive matter—by absolute alcohol | 10.312 | 8.013 |
| Extractive matter—by ether | 1.002 | 1.300 |
| Ashes of clot | 3.000 | 5.691 |
| Peroxide of iron of globules | 1.060 | 2.259 |
| Potassium of globules | 0.329 | 0.625 |