In old dogs. Causes: age, overfeeding on albuminoids, rectal impaction
or irritation, calculus, cystitis, urethritis, productive
inflammation, trophic derangement when function declines. Lesions:
hypertrophy general or partial, hard or soft, condensed or with sacs
of pus, red or pale. Infective cystitis. Calculi. Symptoms: straining
before urine comes, small or weak stream, sudden check, last part
purulent or mucous, incontinence, triple phosphate, ammoniacal odor,
crystals and dark color imply calculus. Diagnosis: by rectal
exploration, and catheterization. Treatment: palliative, moderate,
farinaceous, laxative diet, warmth, correct contiguous troubles,
iodine, castration, extirpation of prostate.
This has been seen almost exclusively in old dogs, among the domestic
animals.
_Causes._ Age and good living, more particularly on highly albuminous
food, may be adduced as the most prominent. Perhaps even more important
are continued irritation in adjacent organs such as the rectum, bladder
and urethra. It is the old, pampered dog that above all suffers from
atonic, overloaded rectum, proctitis, piles, calculus, cystitis, and
stricture, and the constant local pelvic congestion caused by one or
other of these tends to a hyperplasia of the prostate. Again atheroma
which is especially a disease of the aged is regarded as a cause of both
cystitis and prostatic hypertrophy. Chronic inflammation in the prostate
has been claimed as a factor, but contested on the ground that
inflammation never increases normal growth though it may cause
degeneration. The exudate of inflammation, tends, however, on its
temporary arrest, to undergo organization, and such organization
inclines to assume the structure which is normally built up by the
adjacent trophic cells. The products of inflammation may, therefore,
well contribute to hypertrophy, and above all to the increase of the
simpler tissue represented by the fibrous framework of the gland. The
congestion attendant on excessive venery has also been incriminated, and
this too has been denied on the ground that the hypertrophy is not found
in the young animals and men in which the generative ardor is greatest
and most frequently aroused and gratified. Thompson’s idea is that the
prostate, like the ovaries and womb, is especially prone to morbid
growths and developments at the time when in advancing age, the normal
generative functions are undergoing a rapid decline. The two conditions
may well be recognized without considering them as mutually excluding
each other as causative factors.
_Lesions._ The enlargement is usually general, but it may predominate in
the right, left or median lobe, the latter as a rule exercising greater
compression of the urethra so that this is often marked in the worst
cases. The hyperplasia may feel firm and resistant or it may be more or
less soft from sacs of muco-purulent fluid imprisoned by the obstruction
of the outlet canals. On the surface and on section the general
appearance of the gland is pale, bloodless and uniformly solid. This
comes from the great hypertrophy of the fibro-muscular stroma which has
in many cases compressed the parenchymatous or secreting structure so as
to cause its atrophy. The presence of calculi (mainly phosphatic) in the
follicles is not uncommon.
The complication of infective cystitis is frequent, the congestion,
redness, ecchymosis, maculation, puckering and thickening of the mucosa,
the granular degeneration and desquamation of the epithelium, the
exposure of a raw vascular surface, the discoloration of the urine by
mucus, pus and blood, and the formation of ammonia and other products of
decomposition, becoming marked phenomena. Vesical calculus is not
uncommon, the slowness of the exit current of the urine retarded by the
enlarged prostate, tending to prevent its impaction in the orifice and
thus minimizing one of the most prominent symptoms.
_Symptoms._ Among the earliest symptoms, is some modification in the act
of micturition. Straining a few seconds before urine comes, retention,
incontinence and dribbling, discharge in a small or weak stream, and
sudden arrest of the flow and the last few drops may contain muco-pus
showing abundance of spermatic crystals, on the addition of ammonia
phosphate. Impaction of the rectum tends to occur sooner or later, the
animal making little effort to unload the viscus, and the overdistended
organ becoming more and more atonic, congested and catarrhal and
reacting injuriously on the urinary organs. Incontinence may be
especially marked during sleep, the sphincter being sufficiently
controlled by volition during waking hours. Retention may be at first
temporary from excitement and later more continuous by reason of the
greater compression of the neck by the enlarged and indurated prostate.
With the advance of the disease the urine shows abundance of triple
phosphates, and becomes ammoniacal and fœtid. A dark or bloody color of
the discharge and the presence of crystals suggest calculus.
An accurate _diagnosis_ can only be had by rectal examination. The great
enlargement of the prostate, in the absence of heat and tenderness is
characteristic. Enlargement is usually uniform, though it may be
concentrated on the right, left or central lobe. The passage of the
catheter may be obstructed, but is not specially painful at the
prostatic region as in prostatitis. From =vesical calculus= it is
distinguished by the fixity of the swelling on the neck of the bladder
as contrasted with the mobility of the stone inside that half-filled
organ. From =stricture= it is differentiated by the fact that the
obstruction offered to the catheter and the swelling of the prostate
exactly correspond in position, that the stream is lessened in force
rather than simply reduced in size, and that the history of the case
shows no antecedent cause for stricture.
_Treatment._ This has been considered as mainly palliative. Special care
of the general health and above all of the diet which should be
moderate, farinaceous and laxative, protection against cold and wet, the
correcting of any coexisting trouble of the urinary or generative
organs, and the removal from all sources of generative excitement are
important elements. Occasional small doses of Epsom or Glauber salts in
draught or enema obviate rectal hyperæmia. Ergot, potassium iodide
internally, and iodine or mercurial ointment to the perineum have had
little good effect. Möller claims to have secured improvement from the
injection into the prostate at intervals of fourteen days, of a solution
of two parts each of tincture of iodine and iodide of potassium, and
sixty parts of distilled water. A small hypodermic syringe is used and
the injection is made through the rectum directly into the substance of
the prostate. Glass has adopted the recent surgical alternative of
castration, with the result of marked relief from the active symptoms in
a number of cases, but with a more rapid advance through emaciation and
marasmus to death in three or four weeks in others. We would suggest a
careful antiseptic castration in such cases, to obviate any added
trouble from absorbed toxins or sepsis.
For the human subject, Lydston strongly advocates removal of the
enlarged prostate by surgical means in strong, vigorous subjects, with
healthy bladder and kidneys. The difficulty of such an operation in the
dog is greatly enhanced by the relatively greater length of the
pubio-ischiatic symphysis, and the lessened diameter of the pelvic
cavity. Yet with the comparative immunity of the dog from suppuration,
and the hopelessness of the case without such radical measure, and with
the rigid application of an antiseptic technic, the operation would
appear to be fully justified. It would be contra-indicated in all
advanced cases, in which the prostate was the seat of active suppuration
with discharge into the urethra, in cases complicated by urethritis,
cystitis or nephritis, in cases in which there is marked prostration
from sepsis or absorbed toxins, and generally in old, worn out and
cachectic animals.
Short of this, in cases complicated by cystitis, antiseptics by the
stomach and as injections into the bladder are desirable. Eucalyptol in
doses of ten minims four times a day, or beta naphthol, guaiacol, or
phenol have been used in man. As injections mercuric chloride 1:20,000;
boric acid, saturated solution; or carbolic acid ·5:100 (Lydston) may be
used warm several times a day.