Keep calm. The best way to approach this topic is to break it up into smaller chunks. Before starting, read the Chapter Home page first in order to get a broad overview of the approach in this chapter.
To start, we can classify the UG system into THREE main anatomical sections and within each section organise the conditions into main disease categories, so you don’t lose track of the big picture.
Anatomical subdivision: There are THREE natural divisions in the urogenital tract:
- Functions:
- Excrete waste products of metabolism (generate approximately 1L of urine from 1700L of blood daily)
- Maintain salt and water balance in body
- Endocrine organ – secrete hormones
- Erythropoietin
- Renin
- Prostaglandins
- Note – renal diseases not only cause fatality but can also pursue chronic causes and is the cause of significant long term morbidity
Structure:
- Think of kidney as 4 main histological compartments/units
- Glomeruli (FILTERS – often affected by immune mediated conditions)
- Tubules and interstitium (RESORBERS – often affected by infections and toxic agents)
- Vessels (eg. Vasculitis, hypertension)
and
- Pelvicalyceal system (conditions are similar to those affecting the Lower Urinary Tract)
Components: Ureters, urinary bladder, urethra
Functions: Conduit to channel urine from kidneys to bladder for storage and then expulsion through urethra
Main disease categories include:
I. Infectious/Inflammatory conditions (eg. Cystitis – urinary tract infection involving the bladder )
II. Congenital disorders (eg, Vesioreteric reflux; posterior urethral valves)
III. Neoplasmc (eg. Urothelial carcinoma)
IV. Calculi
Since the organs are tubes or hollow organs, obstruction is an important complication of various diseases in the lower urinary tract.
Main disease categories include:
I. Inflammatory / Infectious (eg. Sexually transmitted infections)
II. Congenital (eg. Undescended testes(
III. Neoplastic (eg. Carcinoma of the prostate)
Notice that the categories are practically the same as in the Lower Urinary Tract
Note: You will see the term “renal failure” a lot in this blog. After you finish going through this, refer to your lecture notes for the causes of Acute and Chronic Renal Failure (Lecture III) and try to CLASSIFY them according to what you have learned here (eg. glomerular vs tubulonterstitial vs lower urinary tract), so they are easier to remember.