Diagnosis. — Besides excluding other affections that might lie confounded with pyclitis, it is important to attend to the history of the case with a view to the discovery of the cause; the urinary find ings must also be studied carefully. The vory nature of this affection makes it often most difficult to exclude other af fections of the urinary tract, as nephritis, cystitis, and urcthritis. Any severe in flammation of the tract in which the lower portion is known to be affected is generally associated with pyelitis or pyelonephritis, from the well-known tendency to extension by continuity.
1 Epithelium from the pelvis of the kid ney cannot well be distinguished from transitional bladder-cells; but, given the indications of a pyelitis, its calculous cause is at once made clear upon the pas- 1 sage of the characteristic uratic or oxa latic concretions. It may happen that the urine from one kidney is prevented from flowing by the impaction of a stone • in the ureter. The urine may now flow clear from the other and vicariously act ing kidney until, the stone having given way, it suddenly increases in quantity and changes in character, owing to the return of the morphological elements of the pyelitis (corpuscles, desquamated epi thelium, crystals, and debris).
Catheterization of the ureters and renal pelves, particularly in women, as described and practiced by Pawlik and Kelly, is a certain method of determin ing from which side the purulent urine flows. Palpation of the ureters through the vagina will sometimes reveal thicken ing and tenderness in cysto-pyelitis, and ureteral distension may sometimes be felt in pyelitis ealculosa.
Vierordt mentions having seen in some cases of pyelonephritis, peculiar hyaline casts "split like a pair of trousers." Casts and albumin are usually present when the kidney-structure is involved by extension of the pyelitis, while marked pain in the region of the kidney indicates predomi nant pyelitis, though it does not exclude the possibility of co-existing nephritis. Marked vcsical irritability points to asso ciated cystitis; but in intense pyelitis with much pus and an acid urine, vesical tenesmus may also be troublesome. Tu berculous can be discriminated from cal .
culous pyelitis, possibly, only by a con sideration of the history and general dition, and by the detection of tubercle bacilli in the pus. The presence of a fluctuating tumor in the lumbar region is significant enough of pus, but it is very difficult to determine whether it is due to pyonephrosis or perinephric abscess; the history, pyuria, and less oedematous overlying tissues of the former are impor tant distinguishing points.
The hemorrhagic pyelitis of Senator, Delafield, and others, described as occur ring in milder forms, and particularly in girls of neurotic types, may be revealed by the intermittent hmaturia and occa sional lumbar pain, lasting but a few days or a week, and followed uniformly by recovery. Digestive disturbances may be
prominent in these cases.
Much difficulty is sometimes experi enced in diagnosticating pyelitis when co-existent with cystitis. It should be recollected that their histories differ, pain in the lumbar region being present in the former and in the bladder in the latter; acid pus is usually characteristic of pyelitis.
The following differential points based upon the study of a number of cases, suggested: (1) an alkaline reaction is not found in uncomplicated pyelitis; (2) the maximum of albumin in the urine of cystitis is about 0.15 per cent., while in pyelitis there is not less than two or three times as much albumin; (3) if nearly all the pus-corpuscles are cre nated, pyelitis is probably present; (4) also, if the red corpuscles show chemical and morphological decomposition, if the bmmaturia is microscopical only, and if there is no vesical tenesmus; (5) unless non-imbricated, small epithelial cells should be present, which would favor the diagnosis of some cystitis. Rosenfeld (Berl. klin. Woch., July 25, 'OS).
Surgical kidney, so called, which is an acute suppurative nephritis, is the result of an acute bilateral pyelitis due to the extension upward of a severe cystitis. Acute suppuration or interstitial inflam mation of the kidney due to metastatic or miliary abscesses, occurs as a compli cation of pyemia.
Etiology.—The causes of pyelitis are practically of secondary origin. They are mainly as follows: (1) renal calculi [the most frequent]; (2) urethritis, cys titis, or ureteritis extending upward; (3) retention of decomposed urine in the pelvis of the kidney; (4) renal affections, or tubercle, carcinoma, and acute ne phritis; (5) specific fevers, including in fluenza, perhaps; (6) other foreign bodies than stone; (7) irritating diuretics. Re garding the cause first mentioned, it should be pointed out that calculous pye litis may result from the irritation of the constant presence and passage of small stones ("gravel"), or even of uric-acid "sand," as well as from the large den dritic concretions that send offshoots into the calyces. Extensions of inflammation to the pelvis from lower portions of the ' urinary tract may occur in protracted cases of such affections as gonorrliceal urethritis and puerperal and calculous cystitis. Obstructive pyelitis sometimes follows the impaction of renal calculi or of other foreign bodies in the ureter when there is pre-existing inflammation of the tract or when, as usually happens, there is chemical irritation from the decom position of the accumulated urine. There may be obstruction in the bladder and urethra, as from enlarged prostate, strict ure, or phimosis.