Urology

Hexyl-resorcinol [Call3(OH)2C.H13] is a synthetic compound first described by Leonard. Possessing forty-five times the germi cidal power of phenol, it conforms experimentally to the qualifi cations necessary for an ideal urinary antiseptic in that it is chemically stable, non-toxic, non-irritating to the urinary tract, has an antiseptic and bactericidal action in high dilution in urine of any reaction, and is eliminated in high percentage by the kid neys. On the other hand, it can only exert its germicidal properties on tissues with which the urine comes in contact, and therefore infections of the renal parenchyma and submucous tissues of the urinary tract are not affected by it. If taken on an empty stomach the drug may cause griping or catharsis. Infections due to pyogenic cocci appear to yield to the drug with remarkable rapidity. B. coli infections of the urinary mucosa with a low bacterial count can be cured with hexyl-resorcinol, but when the count is high and the sub-mucous tissues are infected, prolonged treatment combined with appropriate local treatment is necessary. When administered prophylactically two days before, and daily after operations on the bladder, the wounds remain healthy and healing is accelerated.

Tests of Renal Function.

Tests for estimating the function of one or both kidneys are now employed regularly. Though not conclusive, they are capable of giving a warning which should be heeded, particularly in operations on the urinary tract. Thus in prostatectomy they serve to determine a one- or two-stage opera tion, and since they have been adopted as a routine the mortality from uraemia has become almost negligible. The chief tests in use in England are : ( 1) The urea concentration test (Maclean and de Wesselow) ; estimation of blood urea; (3) colour tests. The technique of applying these tests can be found in text-books.

The range of normality of the blood urea is so great that this test alone is of little value unless the urea retention is above 5o mg. per ioo cu.cm. of blood, but when combined with the urea concentration test it gives an excellent indication of the renal efficiency. In some clinics on the Continent great reliance is placed on the elimination of creatinin and chlorides as tests of renal efficiency. The dyes chiefly employed for colour tests are indigo-carmine and phenolsulphonaphthalein. Indigo-carmine can be employed during a cystoscopy and gives a good indication of the function of one kidney without the use of a ureteric catheter (chromGcystoscopy). A 0.4% solution injected either intrave nously (5 c.c.) or intramuscularly (2o c.c.) should tinge the urine of a healthy kidney in five minutes. Phenolsulphonaphthalein is excreted solely by the kidneys and so differs from indigo-carmine, which is only partly excreted by the kidneys. In America it is

used almost exclusively, but in England it has not been popular owing to the somewhat elaborate technique required and to the difficulty, since the War, of obtaining a reliable preparation of the dye. The test is very reliable provided the pure compound is used.

The capacity or otherwise of a patient to resist the spread of sepsis to the upper urinary tract after an operation, such as prostatectomy, is a factor which may upset the calculations of both surgeon and biochemist. MacAdam and Shiskin have found that the cholesterol content of the blood gives a fair indication of the power of resistance. The average in a series of healthy adults under 5o years of age was found to be 0.16%. Above 5o years it ranges between 0.13% and 0.19%. Practical experience led these workers to conclude that in prostatic obstruction a blood cholesterol below 0.13% indicates such a lowered resistance to the spread of sepsis as to constitute a bad operative risk. Cases with a high blood-urea and a normal blood-cholesterol all recovered from a two-stage prostatectomy, but out of eight cases with a high blood-urea and a low blood-cholesterol all died save one.

The Kidney.

Dudgeon and others have pointed out that the combination of pus cells and a pure culture of staphylococcus albus in the urine of one kidney is almost pathognomonic of a stone in that kidney. With certain reservations all cases of renal calculus are now subjected to operation, for the stone, whether causing symptoms or not, slowly but surely injures the kidney and often determines a serious bacterial infection. Small stones are more dangerous than large ones, for they may lodge in the ureter and cause hydronephrosis, anuria and so on.

The problem of bilateral lithiasis is a difficult one, but on the whole urologists advocate operation on the healthiest kidney first, as there is always the possibility that nephrectomy may be neces sary on the side which is more grossly affected. Pyelolithotomy is now performed in preference to nephrolithotomy whenever possible.

Decapsulation of the kidney for nephritis has been performed on many occasions with varying success, but is viewed with increas ing favour. The benefit obtained is probably due to the mechanical relief of renal tension, and this certainly explains the immediate improvement following unilateral decapsulation in eclamptic uraemia. The indications for this operation are uraemia, anuria, oedema, excessive albuminuria and obstinate haematuria. Contra indications are age, heart diseases and extensive cardiovascular changes.