Gastrointestinal/Urinary

Question 1

Briefly describe the pathophysiology of Urinary Tract Infections

Answer 1

Usually develop in lower urinary tract(urethra and bladder), when bacteria enter the urethra and grow.

More common in women due to short urethra, and the proximity of the urethra to the vagina and rectum.
Most commonly bacteria from bowel/colon.

Signs/symptoms:

• dysuria
• urinary frequency
• urgency

UTI in the upper urinary tract(ureters and kidneys) most often develop as a complication of a lower UTI and can lead to pyelonephritis(inflammation of the kidney and upper urinary tract) and abscesses, which eventually reduce kidney function.

In sever cases, untreated UTI’s can lead to sepsis.

Question 2

Briefly describe the pathophysiology of Kidney Stones

Answer 2

Most originate in the collecting tubules or in the renal papillae where they pass into the renal pelvis.

Formed when an excess of insoluble salts or uric acid crystallises in the urine.

Excess of salts typically due to insufficient water intake, to dissolve the salts.

Stones consist of different types of chemicals, dependant on the imbalance of the urine.

Some will be too large to pass through he ureter, causing obstruction that can lead to renal failure.

Others will be small enough to pass through to the bladder, where they may increase in size and block the urethra or be passed in the urine.

Calcium is present in most stones.
Struvite stones occur in the presence of UTI.
Uric acid stones are linked with Gout.
Cystine stones can be inherited(rare).

Question 3

Briefly describe the pathophysiology of Prostatic hypertrophy and urinary retention

Answer 3

Prostatic Hypertrophy:
- enlargement of the prostate caused by hyperplasia of the prostatic tissue in the periurethral area.

• both glandular and stromal cells multiply, but stromal cells much more so.
• peripheral area of the prostate undergo atrophy, and the hyper plastic processes not take place evenly throughout the tissue, instead causing the development of multiple nodules.
• as the central tissue enlarges it impinges on the outflow of the urinary bladder.
• symptoms include:
  
  • frequency
  • urgency
  • nocturia
  • hesitancy
  • incomplete bladder emptying
  • weak urinary stream
• severe obstruction can lead to the development of UTI’s.

Urinary retention:
- describes the inability to urinate.
Causes include:
- urethral stricture
- enlarged prostate(benign/malignant prostatic hypertrophy)
- central nervous system dysfunction
- foreign body obstruction
- certain drugs(parasympholytic or anticholinergic agents)