Bladder outlet obstruction

BOO is a condition characterized by an impediment to the flow of urine from the bladder to the urethra, leading to urinary retention and increased detrusor pressure.

The pathophysiology of BOO is multifactorial and can be caused by a variety of conditions, involving anatomical, neurologic, and functional etiologies. Anatomical causes include BPH, urethral stricture, urethral diverticulum, urethral caruncle, urethral leiomyoma, uterine fibroids, pelvic organ prolapse, rectal cancer, bladder cancer, and bladder stones; neurologic causes include neurogenic bladder; and functional causes include dysfunctional voiding, primary bladder neck obstruction, and Fowler's syndrome.

The prevalence rates of LUTS due to BOO is estimated at 18.7-18.9% and 24.3-24.7% in women and men, respectively.

Risk factors for BOO include age, with older individuals being more susceptible, and gender, with men being more prone due to conditions like BPH. Certain medical conditions like neurological disorders can also increase the risk of BOO. Additionally, iatrogenic causes such as post-surgical retentions (for example, after anti-urinary incontinence surgery) can also contribute to the development of BOO.

Clinically, BOO can present with a range of symptoms from mild urinary frequency and urgency to severe urinary retention. Other symptoms can include a weak or interrupted urine stream, straining to urinate, and a sensation of incomplete bladder emptying.

The prognosis of BOO largely depends on the underlying cause and the timeliness of treatment. If left untreated, BOO can lead to complications such as UTIs, bladder damage, and in severe cases, renal failure.