Lower urinary tract Flashcards
Ureter Congenital Anomalies
-Double and Bifed ureters
-Ureteropelvic junction (UPJ) obstruction
Most common cause of hydronephrosis in infants and children
1 in 500 live births
20% bilateral
-Diverticula
Ureteropelvic Junction Obstruction (UPJ)
Most cases are thought to be due to partial obstruction, because complete obstruction results in rapid destruction of the kidney
symptoms might include:
Abdominal mass Urinary tract infectionwith fever Kidney infection Back or flank pain Bloody urine Vomiting
Inflammation of the Ureter
Ureteritis, though associated with inflammation, is typically not associated with infection and is of little clinical consequence.
Tumors of the Ureters
Primary tumors of the ureter are rare
- Fibroepithelial polyp (Benign mesenchymal neoplasm)
- Urothelial carcinoma (Majority of ureter malignant tumors)
6th – 7th decades
Multifocal (dysplasia – carcinoma-in-situ field effect)
Associated bladder or renal pelvis neoplasms
Obstructive Lesions of the Ureters
- Obstruction of the ureter can lead to hydroureter, hydronephrosis and pyelonephritis
- Unilateral obstruction typically results from proximal causes
- Bilateral obstruction typically arises from distal causes such as prostatic hyperplasia
Sclerosing Retroperitoneal Fibrosis
Fibrosis encasing the retroperitoneal structures occurring in middle to late age
Associated with IgG4 related disease (Rich in IgG4 secreting plasma cells)
Multifocal fibroinflammatory disorder
Ergot alkaloids (methysergide for migraine headaches, vasoconstriction)
Crohn’s disease
Malignancies (lymphomas)
*** Most have no obvious cause (Idiopathic)
Key Concepts: Disorders of the Ureters
Ureteral obstruction is clinically significant because it can subsequently involve the kidney (hydronephrosis or even pyelonephritis), compromising renal function.
In children, congenital ureteropelvic junction (UPJ) obstruction is the most common obstructive lesion in the ureter.
In adults, ureteral obstruction may be acute (e.g., due to obstructing calculi), or chronic (e.g., due to intrinsic or extrinsic tumors or rarely idiopathic conditions such as sclerosing retroperitoneal fibrosis).
Urinary Bladder Congenital Anomalies
Vesicoureteral reflux
- Most common and clinically significant anomaly
Diverticula
- Congenital or Acquired
Exstrophy
- Failure of anterior abdominal wall and bladder development with herniation of urinary bladder through abdominal wall defect
- Urachal anomalies
Urachus persists –> fistula between bladder and umbilicus
***vIncreased risk for bladder adenocarcinoma
Vesicoureteral Reflux
Vesicoureteral reflux (VUR) is a condition in which urine from the bladder has retrograde flow back into the ureter and kidney, usually related to “valve” malfunction.
Most commonly diagnosed in infancy/childhood. About 1/3 of children with recurrent UTI are found to have VUR.
The likelihood of vesicoureteral reflux is related to the length of the ureteral tunnel in the bladder.
Urinary Bladder Diverticula
A pouchlike evagination of the bladder wall
May arise as congenital anomalies but more commonly are acquired due to persistent urethral obstruction
Congenital form may be due to a focal failure of development of the normal musculature or to some urinary tract obstruction during fetal development
Acquired form most often seen with prostatic enlargement producing obstruction to urine outflow and thickening of the bladder wall
Bladder Exstrophy
A developmental failure in the anterior wall of the abdomen and the bladder. The latter either projects directly through a large defect to the body surface or lies as an unopened sac. M=F, W»B
Exposed mucosa may undergo colonic glandular metaplasia and is subject to infections that can spread to the upper GU tract
Patients have an increased risk of adenocarcinoma arising in the bladder remnant
Patent Urachus/Urachal Cysts
Urachus (the canal that connects the fetal bladder with the allantois) is normally obliterated after birth, but it sometimes remains patent in part or in whole
Fistula connecting the bladder with the umbilicus
Central region of the Urachus persists, giving rise to Urachal Cysts
Urachal cysts lined by metaplastic glandular epithelium can give rise to adenocarcinoma
Interpretation of Negative Urine Cultures
Urine is usually sterile. However, contamination with urethral, vaginal or skin flora at the time of collection, and growth of organisms prior to plating, are always concerns (false positive)
Negative – No/few organisms present: Usually indicates that bacterial cystitis is unlikely.***
*** Exceptions include:
Patients on antimicrobial therapy when culture obtained
Patients with mycobacterial or other unusual infectious cystitidies
Interpretation of positive urine cultures
Positive - Clinical interpretation of urine culture isolates depends on:
Specimen Collection Method & Handling: mid-stream clean catch, supra-pubic, etc.
Number of Isolates: Multiple organisms are rarely the cause of cystitis except in patients with chronic indwelling catheters or abnormalities of the urinary tract.
Specific Organisms: Escherichia coli & other coliforms make up 75-90%
Quantity: The dogma > 105 bacteria/mL as evidence of bacterial cystitis has been broadened in recent years.
Acute Cystitis predisposing factors
Bladder calculi Urinary obstruction/structural abnormalities Diabetes mellitus Instrumentation Immune deficiency Institutionalization or hospitalization
