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ANTILITHICS and LITHONTHRYPTICS.
ОглавлениеAntilithics[182] are remedies which have the power of preventing the formation of those mechanical deposites from the urine, which give origin to calculous concretions; and may belong either to the class of Vital, or Chemical Agents.
Lithonthryptics[183] are those medicines which, by a chemical operation, are capable of dissolving calculous concretions.
It has been already shewn, while treating the subject of Diuretics, that certain substances, when internally administered, are capable of passing the barriers of digestion, and of entering the circulation; and that, moreover, these bodies may be again separated by the secretory vessels of the kidneys, and be ejected from the body in the urine. It cannot therefore be contended, that the urinary calculus is placed beyond the sphere of direct medicinal influence, nor can any argument, founded upon the alleged incompatibility of chemical and vital action, be fairly maintained in this case; for the urinary calculus, as well as the urine itself,[184] may very justly be considered as extraneous to the living body. The existence of such a class of remedies as that of Lithonthryptics being thus established, we have to consider the mode and possible extent of their operation in the different varieties of the disease, which they are thus calculated to palliate or cure. In entering upon this inquiry, it is not my intention to prosecute the subject farther than may be necessary to explain the modus operandi of the remedies in question, and in conformity with the object and plan of this work, to establish some general principles that are to direct us in their election, combination, and administration; for farther details the practitioner must consult the systematic treatises of Prout[185] and Marcet,[186] and the very able papers of Mr. Brande,[187] and Dr. Wilson Philip.[188]
The urine may be considered as one of the most heterogeneous of the animal fluids;[189] and since a knowledge of its composition, and that of the morbid changes of which it is susceptible, must constitute the basis of all our knowledge respecting the formation and cure of calculous affections, the following results of an elaborate analysis by Berzelius, are submitted with a view to elucidate our pathological researches.
| Animal Principles. | Water | 933·00 |
| Urea | 30·10 | |
| Lithic Acid | 1·00 | |
| Pure Lactic Acid, Lactate of Ammonia, and Animal matters not separable from these | 17·14 | |
| Mucus of the Bladder | ·32 | |
| Alkaline and Earthy Salts. | Sulphate of Potass | 3·71 |
| Sulphate of Soda | 3·16 | |
| Phosphate of Soda | 2·94 | |
| Phosphate of Ammonia | 1·65 | |
| Muriate of Soda | 4·45 | |
| Muriate of Ammonia | 1·50 | |
| Earthy Phosphates with a trace of Fluate of Lime | 1·00 | |
| Silex | ·03 | |
| 1000·00 | ||
Besides the above ingredients, which appear to be essential to healthy urine, Dr. Prout observes that in different diseases it may contain Albumen, Fibrin, and the red particles of the blood; Nitric acid; various acids, which are found to be modifications of the Lithic; Oxalic acid; Benzoic acid; Carbonic acid;[190] Xanthic Oxide; Cystic Oxide; Sugar; Bile; and Pus.
It will be necessary in this place to make a few observations upon the nature and habitudes of those principles, which are more immediately active in the production of calculi—
1. Urea is a principle peculiar to urine, and must be regarded as a result of the action of the kidneys upon some of the constituents of the blood, perhaps, as Dr. Prout suggests, upon its albuminous matter. For a long time it was regarded as the peculiar principle upon which the colour and other sensible qualities of the urine depended; Berzelius however has corrected this fallacy, and considers that the Lactic acid, and its accompanying animal matters, are the bodies which impart to this fluid the characteristic smell and colour which distinguish it.[191]
2. Lithic, or Uric[192] Acid. As this principle is not found in the blood, but is constantly present in healthy urine, it follows that it must be generated by the action of the kidneys. M. Majendie[193] has lately endeavoured to prove that its secretion depends upon the Azote received in alimentary substances, and for the following reasons, viz. 1. Azote is a component part of Lithic Acid[194]—2. Those persons who use a large portion of animal food, and fermented liquors, are liable to calculous disorders—3. When animals are confined to food which contains no Azote, no Lithic acid is formed—but of this anon.—Berzelius and other animal chemists have supposed that this acid exists in urine in a free state; but Dr. Prout, whose arguments appear very satisfactory and decisive, is of opinion that it is always in combination with ammonia (Lithate of Ammonia), from which however it is very easily separated by the addition of any acid, even the carbonic, in the form of a red powder. It moreover appears to be susceptible of several important modifications, with which it behoves the pathologist to be acquainted; the profession is greatly indebted to the ingenuity and industry of Dr. Prout for some very essential additions to our knowledge, respecting the habitudes of Lithic acid with different bodies.
Erythric Acid. When nitric acid diluted with about an equal bulk of water, is poured upon pure lithic acid, and a moderate heat is applied, an effervescence takes place, and the lithic acid is dissolved; if we then concentrate this solution by a gentle evaporation, we obtain transparent colourless crystals, which have been found to constitute a peculiar acid, to which M. Brugnatelli has given the name of Erythric acid.
Purpuric Acid. Dr. Prout has discovered that if into a strong solution of the above crystals in water, whilst boiling hot, we carefully drop some pure ammonia, the solution acquires a beautiful purple[195] colour, and crystals of purpurate of ammonia speedily begin to form and subside. If these crystals are treated by means of potass and sulphuric acid, pure Purpuric acid is obtained in the form of a yellowish, or cream-coloured powder.
3. The Phosphates. As the Phosphoric acid and its compounds perform an important part in the generation of calculi, their origin[196] and history demand particular attention from the chemist. The Phosphoric acid frequently exists in the urine in a free state, when it would appear to act, like any other acid, as a precipitant of the Lithic acid; this however is not the circumstance that renders its presence formidable; it is to the abundance of its compounds that we are to look for mischief. In healthy urine the phosphoric acid appears to exist in union with soda and ammonia, and partly with lime and magnesia; the latter salts being retained in solution by an excess of acid; but the proportion of these bodies is liable to considerable variation.[197]
Having thus briefly noticed those particular points in the chemistry of the subject with which the therapeutic principles are more immediately connected, we shall be better prepared to examine and appreciate the several plans of treatment which have been proposed for the prevention, cure, or palliation of calculous disorders; and here the subject naturally divides itself into two parts; the one comprehending the modus operandi of Antilithics, or those remedies which prevent or correct the calculous diathesis; the other, explaining the solvent action of Lithonthryptics over concretions already formed.
The line of demarcation by which healthy and morbid urine are separated, is so slight that it is difficult to define its limits; nor would the circumstance appear to be materially important, for the boundary is daily exceeded, not only with impunity, but even without our consciousness of the event; and Dr. Prout has accordingly denominated such occasional deviations, the “Sediments of Health.”
The same enlightened author considers that mechanical deposites from the urine, although composed of the same general ingredients, may, in a pathological point of view, be conveniently divided into three classes, viz. Pulverulent or Amorphous Sediments; 2. Crystalline Sediments, usually denominated gravel; and 3. Solid Concretions, or calculi formed by the aggregation of these latter sediments. The first of these may be passed over, as unconnected with the present subject; the latter however constitutes an essential object of research; for a complete acquaintance with the chemical history of calculi can alone furnish the true indications of cure.
Scheele,[198] with whom the inquiry originated, conceived that every calculus consisted of a peculiar concrete acid, soluble in alkaline lixivia, and which Morveau denominated the Lithic Acid; but the subsequent researches of Fourcroy, Vauquelin, Wollaston, Pearson, Henry, Brande, Marcet, and Prout, have demonstrated the existence of several bodies in the composition of urinary calculi, viz. Lithic Acid; Phosphate of Lime; Ammoniaco-magnesian Phosphate; Oxalate of Lime; Cystic Oxide;[199] and Xanthic Oxide;[200] to which may be added an animal cementing ingredient. The varieties of calculi produced by the combination or intermixture of these ingredients, are represented in the following Tabular Arrangement.
| A TABULAR VIEW OF THE DIFFERENT SPECIES OF URINARY CALCULI. | |||
|---|---|---|---|
| Species of Calculi. | EXTERNAL CHARACTERS. | CHEMICAL COMPOSITION. | REMARKS. |
| 1. Lithic or Uric. | Form, a flattened oval; Specific gravity, generally exceeds 1·500; Colour, brownish or fawn-like; surface smooth, texture laminated. | It consists principally of Lithic Acid; when treated with nitric acid, a beautiful pink substance results. This calculus is slightly soluble in water, abundantly in the pure alkalies. | It is the prevailing species; but the surface sometimes occurs finely tuberculated. It frequently constitutes the Nuclei of the other species. |
| 2. Mulberry. | Colour, dark-brown; texture, harder than that of the other species; Sp. grav. from 1·428 to 1·976. Surface, studded with tubercles. | It is Oxalate of Lime, and is decomposed in the flame of a spirit lamp, swelling out into a white efflorescence, which is Quick-lime. | This species includes some varieties which are remarkably smooth and pale coloured, resembling a hemp seed. |
| 3. Bone Earth. | Colour, pale brown or gray; surface smooth and polished; structure, regularly laminated; the laminæ easily separating into concrete crusts. | Principally Phosphate of Lime. It is soluble in muriatic acid. | |
| 4. Triple. | Colour, generally brilliant white; surface uneven, studded with shining crystals; less compact than the preceding species; between its laminæ, small cells occur, filled with sparkling particles. | It is an Ammoniaco-magnesian phosphate, generally mixed with phosphate of lime; pure alkalies decompose it, extricating its ammonia. | This species attains a larger size than any of the others. |
| 5. Fusible. | Colour, greyish-white. | A compound of the two foregoing species. | It is very fusible, melting into a vitreous globule. |
| 6. Cystic. | Very like the Triple Calculus, but it is unstratified and more compact, and homogeneous. | It consists of Cystic Oxide; under the blow-pipe it yields a peculiarly fetid odour. It is soluble in acids, and in alkalies even if they are fully saturated with carbonic acid. | It is a rare species. |
| 7. Alternating. | Its section exhibits different concentric laminæ. | Compound of several species, alternating with each other. | |
| 8. Compound. | No characteristic form. | The ingredients are separable only by chemical analysis. |
Let us now inquire into the circumstances under which the several substances enumerated in the foregoing table, are found to be deposited; and first of the Lithic acid Diathesis. It has been already stated, that the lithic acid exists in the urine in combination with ammonia, so as to be held in solution under ordinary circumstances; if however any free acid be generated, the lithic acid is immediately precipitated, giving rise to the appearance so well known under the name of red gravel; from this view of the subject the lithic acid deposite must be considered as arising, not from the excess of that substance in the urine, but from a decomposition of the compounds into which it enters by the agency of a free acid. M. Majendie is therefore incorrect in attributing its appearance to the quantity of azote in the ingesta; an opinion which has been very ably controverted by Dr. Philip, in a paper published in the sixth volume of the Medical Transactions. It appears, moreover, that whatever tends to disturb the process of digestion, by favouring the production of acid, may be considered as the exciting cause of the lithic deposites; especially where the cutaneous functions are imperfectly performed; for Dr. Philip is of opinion, that the precipitating acid, in a healthy state of the system, is thrown off by the skin; and he supposes that even when generated in excess, it may be diverted to the surface of the body by merely increasing the insensible perspiration. The medical treatment of the lithic diathesis is thus rendered simple and satisfactory; and if the opinion of Dr. Prout be true, that at least two-thirds of the whole number of calculi originate from lithic acid, the extreme importance of the subject is too apparent to require comment. Remedies, medicinal and dietetic, that are capable of correcting dyspeptic symptoms, such as slight bitters,[201] will doubtless prove valuable resources; while all those agents which have a tendency to correct and regulate the insensible perspiration, will necessarily fall under the head of anti-lithic remedies. Mr. Copland Hutchison, in a paper which has been published in the Transactions of the Medico-Chirurgical Society, has shewn a comparative rarity of calculous disorders in British seamen. Can the quantity of muriate of soda taken with their food, from its stimulating influence upon the cutaneous functions, be considered as affording a plausible explanation of this fact? The Phosphatic Diathesis seems to be accompanied with considerable derangement of the chylo-poietic viscera, and Dr. Prout very justly remarks, what I have frequently observed, that the stools are extremely unnatural; as the phosphates are retained in solution by an excess of acid, it would appear as if an alkaline principle was occasionally developed, and it is not unreasonable to suppose that this may be sometimes derived from bilious regurgitations;[202] in some cases, the alkali is derived from the spontaneous decomposition of urine itself, especially where the bladder has lost its governing power,[203] as from some injury[204] of the spine; or from some local affection of the bladder or prostate gland; wherever the urine undergoes an incipient process of decomposition, ammonia will be generated, and an ammoniaco-magnesian phosphate[205] be immediately precipitated: hence in cases where the bladder is unable to discharge its contents, this deposite is very apt to take place, as in diseases in the prostate; and this explains the reason why the triple phosphates are so frequently formed in elderly people, who cannot wholly evacuate their bladder.
It will appear evident from these cursory observations, that some varieties of Calculi will be influenced by acids, and others by alkalies, and that the exhibition of such remedies will be liable to palliate, or to aggravate the symptoms, according to the character and composition of the offending calculus, and according to the prevailing diathesis of the patient; as a general rule to direct us in the chemico-medical treatment of these cases, Dr. Marcet states, that “Whenever the lithic acid predominates, the alkalies[206] are the appropriate remedies, but that when the calcareous or magnesian salts prevail, the acids are to be resorted to.” But if it be asked how we are to discover the nature of the calculous affection, so as to direct the suitable remedy? the reply is obvious—by an examination of the sediment deposited by the recent urine, or by an analysis of the small fragments which are frequently voided with it; the Phosphates subside from the urine as a white, lithic acid, generally, as a red deposit; and since the phosphates are held in solution in the urine by an excess of acid, it is evident that whenever such acidity is diminished by the hand of Nature or art, a white sabulous deposit will ensue; hence, says Mr. Brande, it occurs in the urine of persons who drink soda water, or take magnesia; the remedy of such a deposit, when it takes place habitually, is a course of acidulous medicines; on the contrary, since lithic acid is precipitated by the acids, alkalies are naturally suggested for the prevention of that deposit. In the compound calculi, acids and alkalies may be equally injurious or beneficial, for since these bodies are composed of a variety of ingredients, the action of any one solvent must be partial, and may convert the smooth calculus into a rough and highly irritating body, or vice versa. In the alternating calculi it may be judicious to exhibit these remedies alternately, as the symptoms of the case and the deposit of the urine may indicate. After all, however, the solvent powers of Lithonthryptic remedies must be very limited, and in advanced cases we can never expect to procure more than palliation. With respect to the agency of these different remedies, as Antilithics, I would observe, that while experience bears us out in confiding in the production of certain chemical effects from their use, we must not forget that much is to be effected by their judicious administration as vital agents: and it will be hereafter my duty to point out the many advantages that may be obtained, by combining in one formula, medicines which individually belong to each class.
Independent of any chemical effect, alkaline substances are found by daily experience to allay the morbid irritability of the urinary organs in a manner not yet explained; alkalies may also prove generally serviceable in these disorders, by acting immediately upon the digestive organs, for the disposition of forming calculi is always, more or less, accompanied with the indications of deranged digestion; and it is probable that the first link of the series of actions, which cause this disposition, has its origin in the stomach.
The alkaline carbonates are found to answer as effectually as the pure alkalies, and they have the advantage of being less liable to disagree with the stomach. Mr. Hatchett has proposed the carbonate of magnesia, in doses of ℈j to ʒj, as a valuable substitute for alkaline remedies in cases of lithic calculi; but as its insolubility must render its absorption equivocal, the beneficial operation of the substance must principally depend upon its neutralizing any excess of acid in the primæ viæ, and in this way there can be no doubt of its lithonthryptic agency; “but,” says Dr. Marcet, “such is the tendency which the public has to over-rate the utility of a new practice, or to take a mistaken view of its proper application, that there is every reason to believe that the use of magnesia has of late years become a frequent source of evil in calculous complaints.” Lime-water has been also recommended for the purpose of fulfilling the same indications, and as not being liable to produce that irritability of stomach which frequently attends the long continued use of the fixed alkalies; besides which, some chemists have maintained that it exerts a peculiar solvent power over the cementing animal matter of the concretion, and thereby destroys its cohesion.[207]
Where an acid is indicated, the Muriatic will in my judgment be found as convenient and effectual as any that can be administered. Mr. Brande proposes Cream of Tartar for this purpose; upon this point I differ with him, for this salt, to say the least of it, is questionable in its mode of operation; for although its first impression upon the stomach is that of an acid, the subsequent processes of digestion decompose it, and eliminate its base, which being absorbed acts upon the urinary organs as an alkali. I have seen a white sabulous deposit, consisting of the Phosphates, in the urine of persons after the constant use of Imperial as a beverage, which I am at a loss to explain upon any other principle. Sir Gilbert Blane has also very satisfactorily shewn, that a fixed alkali produces the same effect upon the urinary organs whether it be exhibited alone, or in combination with citric acid; in this latter case the salt undoubtedly undergoes a decomposition in transitu, as I have more fully explained under the consideration of Diuretics, (page 94.) During an alterative course of Lithonthryptic remedies it may be beneficial to interpose occasionally a purgative medicine, but we must not combine it with the lithonthryptic, at least, if we wish this latter medicine to reach the urinary passages; for it is a law which I have already attempted to establish (see page 94), that Catharsis suspends the process of alimentary absorption.
There remains to be considered another mode of applying a solvent, and which would seem on the first view of the subject to be full of promise,—that of injecting the proposed menstruum into the bladder. Unfortunately, however, the irritable state of this organ will generally preclude the possibility of preserving the menstruum, for a sufficient length of time, in contact with the calculus to accomplish any material solution; nor am I aware that any case, in favour of such a practice, stands recorded. An ingenious and novel application of the powers of Electro-chemistry has been lately[208] proposed by M M. Prevost and Dumas, as capable of affording means for the solution of the calculus within the bladder; the suggestion is highly plausible, and ought not to be hastily rejected without trial. Could the functions of the part be protected against the influence of so powerful an agent, it is evident that, by a galvanic battery of sufficient intensity, a calculus composed of alkaline or earthy salts might be transferred from the bladder by the simple introduction of a double sound, communicating on one hand with the calculus, and, on the other, with two vessels filled with water, in which are plunged the opposite poles of a galvanic apparatus.[209] This arrangement would transfer the acid constituents into the vessel connected with the positive end, and the bases into that of the negative end. So far, however, as the experiments have hitherto been carried, this degree of galvanic operation would seem to excite too much irritation in the bladder to be admissible; but it still offers a resource of an apparently more practicable nature. This consists in giving to the calculus a tendency to crumble from the slightest force; such a friability, in short, as shall render it easily broken into pieces sufficiently small to be evacuated through the urethra, especially by the aid of dilating that passage, an operation upon which much has lately been said and written. A fusible calculus from the human subject was submitted to the action of a pile, consisting of 120 pairs of plates, for twelve hours in succession. The platinum wires, constituting the poles, were placed in contact with the calculus, about six or eight lines distant from each other, and the whole plunged in a vessel filled with pure water. During the galvanic action, the bases and phosphoric acid first arrived at their respective poles, then re-entered into combination, when the salt thus reformed was precipitated in the state of powder. The calculus weighed 92 grains before the experiment, and was reduced at its termination to 80. The process being continued, at the end of sixteen hours it presented a mass of such friable texture as to be reduced into small crystalline particles by the slightest pressure; the largest of which did not exceed the size of a lentil, so that it might have easily passed through the urethra.
In order to ascertain how far this decomposition could be effected in the living body, the ingenious experimentalists selected a dog of rather large size, into whose bladder they introduced a fusible calculus attached to a sound, and between two conductors of platinum; the bladder was next distended by injecting tepid water, and the apparatus subjected to galvanic influence. After a little struggling, the animal became calm, and was subjected to the operation during an hour. On removing the sound, the calculus shewed unequivocal marks of decomposition. The same process was repeated, night and morning, during six days, when the friability of the calculus rendered it impossible to continue the experiment. It had lost weight in the same proportion as in the preceding trial. The bladder, which was afterwards examined, exhibited no appearance of injury or disease.[210] The authors assert that this organ does not suffer any inconvenience from this more moderate degree of galvanic action, and suggest, as a proof of the mildness of its influence, that we should immerse the tongue in a vessel filled with water, in which a calculus is undergoing decomposition, and it will be found that the tongue, which is far more sensible than the bladder, will scarcely perceive the galvanic action, even when decomposition is going on briskly. The authors add, that this process cannot offer any advantage for the removal of those calculi which consist wholly of Uric acid, or which contain a large proportion of it.[211]
