Urinary Bladder Pathology

2021-02-23 12:00 AM

Congenital anomalies of the bladder. Exstrophy of the bladder is a developmental failure of the formation of the abdominal wall and bladder which leaves the bladder open at the body surface.


Congenital anomalies of the bladder. Exstrophy of the bladder is a developmental failure of the formation of the abdominal wall and bladder which leaves the blad-der open at the body surface. Urachal cyst remnants may permit drainage of urine from a newborn’s umbilicus, and may also be a cause of bladder adenocarcinoma.

Cystitis. The aetiology of cystitis varies, with important causes including organ-isms, notably from faecal flora (Escherichia coli, Proteus, Klebsiella, Enterobacter); radiation cystitis (may follow radiation therapy); and chemotherapy agents such as cyclophosphamide (hemorrhagic cystitis).

Clinically, it affects females far more than males. Symptoms include frequency, urgency, dysuria, and suprapubic pain; systemic signs such as fever and malaise are uncommon. Predisposing factors include benign prostatic hypertrophy, bladder calculi, and cystocele.

Malakoplakia is a bladder inflammatory pattern associated with a defect in macrophage function. The cause is unknown. Macrophages contain Michaelis-Gutmann bodies, laminated basophilic structures.

Urinary bladder tumours are most commonly due to transitional cell carcinoma. There is an increasing incidence of urinary bladder tumours; males are affected more than females, and the peak incidence is age 40-60. Risk factors include:

  • Cigarette smoking and occupational exposure to azo dye production (transitional cell carcinoma) (both due to 2-naphthylamine)
  • Chronic bladder infection with Schistosoma haemotobium(squamous cell carcinoma) (Africa including Egypt and the Middle East)

Bladder cancer usually presents with painless hematuria, but it may also cause dysuria, urgency, frequency, hydronephrosis, and pyelonephritis.

The prognosis of bladder cancer depends on the tumour grade and stage. There is a high incidence of recurrence.

Precursors of invasive transitional cell carcinoma can arise from a flat or papillary lesion.

  • Carcinoma in situ (CIS) is a high-grade lesion with cytologic atypia in the full thickness of the epithelium. It is frequently multifocal. In 50-75% of untreated cases, it progresses to invasive cancer.
  • Papillary precursors to invasive carcinoma include papilloma⇒ papillary urothelial neoplasia of low malignant potential  low-grade urothelial carcinoma  high-grade urothelial carcinoma.

Other bladder tumours include papillomas, adenocarcinoma, and embryonal rhabdomyosarcoma.

Miscellaneous bladder conditions

  • Acquired diverticula can complicate urinary tract outlet obstruction due to benign prostatic hyperplasia or other causes.
  •  Cystocele is the term used for prolapse of the bladder into the vagina. It is common in middle-aged to elderly women.
  •  Cystitis cystica et glandularis causes the formation of small cysts and glands in the bladder mucosa related to chronic inflammation. It is associated with an increased risk of adenocarcinoma.