I. Common Ureteral Disorders
A. Congenital megaloureter
• May be associated with Hirschsprung disease
B. Ureteritis cystica
1. Disorder is a manifestation of chronic inflammation.
2. Smooth cysts project from the mucosa into the lumen.
• Similar findings may be present in the bladder.
3. Cysts may undergo glandular metaplasia and predispose to adenocarcinoma.
C. Ureteral stones
• Ureters are the most common site for stones to cause obstruction.
D. Retroperitoneal fibrosis
1. Causes
a. Most cases are idiopathic.
b. Known causes/associations include:
(1) Ergot derivatives used in the treatment of migraines
(2) Retroperitoneal malignant lymphoma
(3) Association with other sclerosing conditions
(a) Primary sclerosing cholangitis (PSC)
(b) Sclerosing mediastinitis, Reidel fibrosing thyroiditis
2. Complications
a. Hydronephrosis is the most common complication.
b. It may cause a right scrotal varicocele (see section V).
• Blocks the drainage of the right spermatic vein into the vena cava
E. Ureteral cancers
• Transitional cell carcinoma (TCC) is the most common cancer.
II. Urinary Bladder Diseases
A. Congenital diseases of the urinary bladder
1. Exstrophy of the bladder
a. Developmental failure of the anterior abdominal wall and bladder
(1) Bladder mucosa is exposed to the body surface.
(2) It is often associated with epispadias (see section IV).
b. Complications
(1) Inflammation predisposes to glandular metaplasia.
(2) The likelihood of developing adenocarcinoma of the bladder is high.
2. Urachal cyst remnants
a. Usually the embryonic allantois (part of the yolk sac) is obliterated to form the fibrous
urachus connecting the apex of the bladder with the umbilicus (called the median
umbilical ligament in adults).
• If the lumen remains patent in the newborn, fistulas may develop between
the bladder and the umbilicus; midline cysts may persist that may drain
urine.
b. Cyst remnants predispose to adenocarcinoma of the bladder
• Most common cause of bladder adenocarcinoma
B. Acute and chronic cystitis
1. Risk factors for lower urinary tract (LUT) infection
a. Female sex
(1) Short urethra
(2) Ascending infection (refer to Chapter 20)
b. Indwelling urinary catheter
(1) Most common cause of sepsis in hospitalized patients
(2) Account for 50% of nosocomial urinary tract infections (UTIs)
c. Sexual intercourse
(1) “Honeymoon cystitis” occurs from trauma to the urethra.
(2) Voiding after intercourse reduces the risk for infection by washing out bacteria in
the urethra.
d. Diabetes mellitus, neurogenic bladder
e. Cyclophosphamide
(1) Produces hemorrhagic cystitis
(2) Prevented with mesna
f. Schistosoma haematobium
(1) Transmission
(a) The fork-tailed cercariae penetrate the skin.
(b) Larvae enter veins in the urinary bladder wall.
(c) Larvae develop into adult worms that deposit eggs.
(d) Host develops an intense inflammatory response consisting of
eosinophils that surround the eggs.
(e) Inflammation causes squamous metaplasia of the bladder
epithelium.
(2) Eggs have a large terminal spine (see Fig. 21-1B).
(3) Treatment is praziquantel.
2. Causes of acute cystitis
a. Escherichia coli
(1) Most common uropathogen (80%–90% of cases)
(2) Gram-negative rod (see Fig. 21-1C)
(3) UTIs account for 40% of hospital-acquired (nosocomial) infections.
(4) Most common cause of sepsis in a hospitalized patient
(5) Treatment is double-strength trimethoprim-sulfamethoxazole.
b. Adenovirus
• Causes hemorrhagic cystitis
c. Staphylococcus saprophyticus
(1) Causes acute cystitis in young, sexually active women
• Accounts for ~10% to 20% of LUT infections
(2) Coagulase negative
(3) Treatment is oral cephalosporin or amoxicillin-clavulanate.
d. Acute urethral syndrome in women
(1) Female counterpart to nonspecific urethritis (NSU) in men
(2) Chlamydia trachomatis is the most common cause of acute urethral syndrome.
(3) Identification of Chlamydia
• Polymerase chain reaction (PCR) testing of voided urine
(4) Treatment is azithromycin
e. Other uropathogens
• Mycoplasma hominis, Ureaplasma urealyticum, Neisseria gonorrhoeae
3. Clinical findings in LUT infections
a. Dysuria (painful urination)
b. Increased frequency, urgency, nocturia
c. Suprapubic discomfort
d. Gross hematuria
4. Laboratory findings in LUT infections
a. Pyuria ≥10 white blood cells (WBCs) per high-power field (HPF) in a
centrifuged specimen
• More than 2 WBCs/HPF in an uncentrifuged specimen
b. Bacteriuria, hematuria
c. Positive dipstick for leukocyte esterase and nitrite (refer to Chapter 20)
d. Culture showing at or above 105 colony-forming units (CFUs)/mL
• Gold standard criterion of infection
5. Asymptomatic bacteriuria in women
a. Two successive cultures with 105 or more CFUs/mL in an asymptomatic
patient
b. Causes
(1) Pregnancy
• Acute pyelonephritis may occur in 1% to 2% of cases.
(2) Elderly women in nursing homes
c. Treatment
(1) Pregnant women
• Amoxicillin
(2) Asymptomatic, healthy elderly women
• No treatment necessary
6. Sterile pyuria
a. Neutrophils in the urine and negative standard culture after 24 hours
• Positive leukocyte esterase, negative nitrite
b. Causes
(1) C. trachomatis
(2) Renal tuberculosis (TB)
(3) Acute tubulointerstitial nephritis (TIN; refer to Chapter 20)
7. Malacoplakia
a. Associated with a chronic E. coli infection of the bladder
b. Microscopic findings
(1) Yellow, raised mucosal plaques
(2) Foamy macrophages filled with laminated mineralized concretions
• Called Michaelis-Gutmann bodies, which are defective phagosomes that cannot
degrade bacterial products
C. Miscellaneous diseases of the urinary bladder
1. Acquired diverticula
a. Most are due to benign prostatic hyperplasia (BPH)
b. BPH causes obstruction of urine outflow and increased intravesical pressure,
predisposing to diverticula formation through areas of weakness.
c. Diverticulitis and stone formation are common complications.
2. Cystocele
a. Common in middle-aged to elderly women
b. Mechanism
(1) Relaxation of pelvic support causes descent of the uterus
(2) Bladder wall protrudes into the vagina
• Creates a pouch that collects residual urine
3. Cystitis cystica and glandularis
a. Bladder analog of ureteritis cystica
b. Increased risk for developing bladder adenocarcinoma
III. Urethral Diseases
A. Infections of the urethra
1. Chlamydial and gonococcal infections in men and women
• Urethra is the most common site for these sexually transmitted diseases (STDs).
2. Nonvenereal diseases causing urethritis
a. Most commonly due to E. coli
b. Complications
(1) Cystitis in women
(2) Prostatitis in men
3. Chlamydial urethritis is a common component of Reiter syndrome in men.
a. Urethritis
b. Sterile conjunctivitis
c. Human leukocyte antigen (HLA)-B27–associated arthritis (refer to Chapter 24)
B. Urethral caruncle
1. Female dominant disease
2. Friable, red, painful mass is present at the urethral orifice.
3. Chronically inflamed granulation tissue causes bleeding.
C. Squamous cell carcinoma of the urethra
• Most common cancer of the urethra
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