CAUSES :
1. CONGENITAL
- URETEROPELVIC JUNCTION NARROWING OR OBSTRUCTION
- URETEROVESICLE JUNCTION NARROWING OR OBSTRUCTION
- URETEROCELE
- RETROCAVAL URETER
2. ACQUIRED INTRINSIC DEFECTS
- CALCULI
- INFLAMMATION
- TRAUMA
- SLOUGHED PAPILLAE
- TUMOR
- BLOOD CLOTS
- URIC ACID CRYSTALS
3. ACQUIRED EXTRINSIC DEFECTS
- PREGNANT UTERUS
- RETROPERITONEAL FIBROSIS
- AORTIC ANEURYSM
- UTERINE LEIOMYOMATA
- CARCINOMA OF UTERUS, PROSTATE, BLADDER , COLON , RECTUM
- LYMPHOMA , PELVIC INFLAMMATORY DISEASE
- ACCIDENTAL SURGICAL LIGATION
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SECOND CLASSIFICATION OF CAUSES :
. Intrinsic, congenital
. Stenosis (ureteral, urethral and meatal)
. Adynamic ureter
. Spinal cord defects, e.g., spina bifida
. Bladder neck obstruction
. Duplication of the ureter
. Ureterocele
. Intrinsic, acquired
. Prostate hyperplasia, carcinoma
. Renal lithiasis (most common)
. Neoplasm (renal, ureteral or bladder)
. Papillary necrosis with sloughed papilla
. Ureterocele
. Trauma
. Blood clot
. Fungus ball
. Granuloma (tuberculosis)
. Neurogenic bladder
. Other nervous system diseases - tabes dorsalis, multiple sclerosis, diabetic neuropathy, traumatic spinal cord injury
. Anticholinergics
. Phimosis, ureteral valve, polyp or stricture
. Schistosomiasis (hematobium)
. Wegener granulomatosis
. Psychogenic polydipsia
. Imperforate hymen
. Extrinsic
. Retroperitoneal-neoplasm, blood, abscess, fi brosis, aneurysm
. Crohn disease
. Lymphocele, hydrocele
. Fecaloma
. Gynecologic - gravid uterus, endometriosis, pelvic inflammatory disease, abscess, cyst, gynecologic malignancy, uterine prolapse, uterine leiomyomata
. Sjogren syndrome (pseudolymphoma)
. Functional or non-mechanical - congenital
. Mega-ureter
. Prune belly syndrome
. Extra-renal pelvis
. Functional or non-mechanical - other
. Accidental surgical ligation
. Diabetes insipidus
. Diuretics
. Vesicoureteral reflux
. Postobstructive residual
. Postsurgical: post ureteral anastomosis, adhesions
. Progestational agents
β’ May be normal
β’ Azotemia
β’ Hyperkalemia
β’ Metabolic acidosis (with and without anion gap)
β’ Hypernatremia (nephrogenic diabetes insipidus)
β’ Urine analysis - hematuria, crystals, bacteriuria
β’ Decreased urine concentrating ability
β’ Polycythemia (rare)
β’ Anemia of chronic renal disease
OTHER TESTS - EXCRETION UROGRAPHY, RETROGRADE OR ANTEGRADE.
* ISOTOPE RENOGRAPHY - TECNITIUM-99 LABELLED DTPA SCAN OR MAG-3 SCAN - SHOWS BLOOD FLOW TO THE KIDNEYS, RENAL FUNCTION & ANY OBSTRUCTION IN THE URINE OUTPUT.
* RETROGRADE PYELOGRAPHY
* WHITAKER TEST - PERCUTANEOUS INFUSION OF FLUID IN RENAL PELVIS
SPECIAL TESTS
. Voiding cystourethrogram
. Post void residual
. Ultrasound prostate with biopsy if nodule found
. Prostatic specific antigen (malignancy); controversial - yes (American Cancer Society), no (National Cancer Institute)
. Prenatal sonography
. Rectal examination in males age > 50
IMAGING
. Kidney ureter bladder (KUB) plain film
. Unenhanced helical CT for lithiasis
. Ultrasound - abnormal renal function, cortical thinning, ureteral dilatation
. IVP with tomograms (normal renal function): Renal pelvis dilatation
. Renal flow scan, diuretic renogram
. CT scan; MRI
. Pulsed and color Doppler
. Diuretic enhanced duplex Doppler sonography
DIAGNOSTIC PROCEDURES
. To determine location and etiology:
. Cystoscopy/retrograde pyelography
. Antegrade pyelography
. Loopography (obstruction with ureteral diversion)