Stone in the bladder is more frequent than stone in the kidney.

Symptoms

The early symptoms are imperfectly known, as advice is rarely sought until the stone or stones have acquired sufficient size to interfere with the functions of the bladder. When this is the case, stone gives rise to irritability of the bladder, with frequent scanty discharges; severe pain, worse after urine has passed, and whilst moving; discharge of a few drops of blood; unsheathing of the glans penis; straining efforts, etc. The stone or stones may possibly be felt through the walls of the belly, or by the finger in the rectum. The only sure way of positively affirming the presence of stone in the human bladder, viz., the use of the "sound," has not, as far as I am aware, been resorted to in dogs.

Stone in the bladder follows the presence of any foreign body, even of the smallest size. A minute renal calculus that has made its way into the bladder may form a nucleus round which the constituents of a bladder-stone are slowly deposited. Boerhaave introduced a small pebble into a dog's bladder; a few months afterwards the dog was killed, and a large calculus found with the pebble in its centre. As many as fifty calculi, of different sizes, have been found in the dog's bladder.

There are four varieties of vesical calculi: * -

1. Form, rounded and elongated; surface, yellowish white, and roughened by isolated crystals of the ammonio-magnesian phosphate; the calculi may acquire a considerable size and weight; the nucleus and strata have the same composition. Ammonio-magnesian phosphate, phosphate and carbonate of lime, uric acid (which is sometimes absent), and organic matter are the ingredients of this variety.

2. Much smaller than the last, rarely reaching the bulk of a small walnut; angular and usually triangular in form; their smooth surface is of an unspotted white colour; sawn through, they present layers surrounding a hard nucleus or kernel; they are found collected in large numbers, - the bladder of an old dog contained upwards of one thousand and ten; they vary in size from a grain of sand up to a hazel-nut. They have the same chemical composition (though not in the same proportion) as the preceding variety, except that they contain no uric acid.

3. Small round bodies, from the size of mustard-seed to that of a small pea, and having a yellowish, smooth, shining, greasy surface. This variety is the most unfrequent. A section of it has the appearance of wax, with an indistinct crystalline structure towards the centre. They are composed of cystine.

* Nouveau Dictionnaire Pratique de Medicine Veter., etc. Art. Calcul.

4. As rare as the last variety; the surface is yellowish, rough and chalky, and crumbles when touched; the nucleus is formed of cystine, and the calculus is made up of alternating layers of cystine and carbonate of lime. The other constituents, in addition to cystine, are carbonate of lime, a trace of ammonio-phosphate of magnesia, and organic matter.

In speaking of the palliative treatment of stone - for the radical cure of such a case by mere medicines has yet to be discovered, - Mayhew makes the following sensible remarks: - "Very minute doses of cantharides have seemed to be attended with benefit. Here, however, I speak with doubt, for the agents have by me been employed only in homoeopathic quantities, and I have not the means of saying they had very decided action. They appeared to do good, since under their use the animals improved; and that is all I can state in their behalf." It seems very probable to me, that the quantities incorrectly called "homoeopathic" - since homoeopathic is not synonymous with minute or infinitesimal - not only "appeared to do good," and "seemed to be attended with benefit," but were good and beneficial, and the proof is that "under their use the animals improved."

Besides Cantharis, much relief may be given by Aconitum,* Belladonna, Nux vomica, and Cannabis.

* For the dose, etc., of these remedies, consult "Introductory Remarks."

The indications for each of these remedies have been already given tinder the descriptions of the diseases of this chapter.

The removal of the stone by operation has been proposed, but never practised, as far as I am aware.