The presence of pus in the urine is frequently seen in connection with a renal calculus, and when taken together with other symptoms is evidence that inflammatory changes are in existence which may terminate in the disorganization of the organ. It is a symptom, in conjunction with attacks of renal colic, of grave importance.
In the early stages connected with the impaction or rather reten tion of gravel within the kidneys, a very considerable increase in the amount of mucus in the urine may be observed. It is not uncom mon to find in cases of this kind, on placing the excretion in a urine glass and letting it stand for some time, that though blood and pus may be absent the amount of mucus is often doubled or even trebled, while its density is increased. This is a symptom of considerable importance, especially in young persons who are not likely to have any prostatic enlargement. Sufficient stress is not always placed upon this point.
As Sir William Roberts has pointed out, renal stones may some times be latent and quiescent so far as all. symptoms are concerned. This author remarks : " Renal symptoms may exist for a longer or shorter period, and then wholly and finally cease. This latter event may occur under two circumstances; either the concretion completely occludes the ureter, and determines gradual atrophy of the kidney, or it becomes encysted in a lateral pouch or cliverticulum and ceases to impede the flow of urine and to irritate the mucous membrane." The diagnosis of renal calculi is not usually attended with much difficulty, though in the case of cortical stones, as already remarked, the symptoms are not always well pronounced. As with the bladder, stationary stones do not so readily declare themselves as those that alter their position somewhat in accordance with the movements of the body. The diagnosis of renal calculus has in some instances been aided by the surgeon recognizing from the loin on manipulation a characteristic grating when more than one calculus was present.
Suppression of urine is occasionally met with as a consequence of the presence of calculus affecting both kidneys, or when only one kid ney exists. There is a case recorded by Dr. D. Newman where death followed suppression of urine which had existed for five days. At an autopsy, symmetrical blocking of both m.eters with calculi was found. Mr. Godlee records a case where large calculi were removed from both kidneys in successive operations, and Mr. Lucas cites an
instance where nephro-lithotomy (following nephrectomy) for total suppression of urine was permanently successful.
The conditions which may in some degree resemble renal calculus are the periodical discharge of large quantities of crystalline material down the urinary apparatus as we see in certain gouty subjects, as well as the subacute symptoms which sometimes arise in connection with the passage of organized substances from the kidney downward, as occurs in cases of tubercular and cystic kidney and in hydatids of this organ. A storm of uric acid crystals, for instance, in their tran sit downward from the kidney may cause symptoms closely re sembling those of renal colic. There is local pain and spasm, aching down the thighs or sensations in the testicles, not much less severe than when a stone in passing, and occasionally the urine is tinged with blood. It is a form of gout which generally ends in this way when the symptoms gradually subside. Oxalate of lime crystals in some dyspeptic subjects may produce similar effects. The micro scope serves to provide the means of making the diagnosis in these instances.
The debris caused by the disintegration of tubercular abscesses and its escape down the ureters will sometimes provoke much renal colic, in the same way that the colloid contents of cysts opening into the kidneys will do. These conditions, however, are not very likely to be mistaken for those of renal calculus, though they may be the cause of very considerable intermittent pain.
I have recently seen a case in which a woman for a long period was supposed to suffer periodically from the colic of kidney stone, and the attack certainly had a close resemblance to the latter, judging from the description that was given. This conclusion was somewhat strengthened by the fact that I had removed a uric acid calculus from the bladder of her father by crushing. However, when the urine came to be examined the presence of hydatids was readily discovered in the excretion, which observation was corroborated by a physical ex amination of the loin. Hence in all instances where there is pain such as we get with the movement of calculi in kidney, the urine should be carefully tested, and examined with the microscope, before a conclusion is arrived at.