diseases of the urinary system 2 Flashcards
Pelvic causes of urinary tract obstructions
renal stones
renal strictures
renal tumours
stag-horn calculi
Intrinsic causes of urinary tract obstructions
calculi tumour clots sloughed papillae inflammation
Extrinsic causes of urinary tract obstructions
pregnancy- obstruction of distal ureter due to utreus and prostaglandins.
tumour- e.g. cervical
bladder causes of urinary tract obstructions
calculi
tumours
viscioureteral reflux- valve doesn’t work so when the bladder is full urine passes back up the ureter.
urethral causes of urinary tract obstructions
valave stricture
prostatic causes of urinary tract obstructions
hyperplasia, carcinoma, prostatins.
what are the 4 categories of obstructions in any environment
obstruction within lumen
abnormalities of the wall
external compression
functional obstruction
define sequeale
a condition which is the consequence of previous disease or injury.
what are the consequences of a complete obstruction.
Reduced glomerular filtration rate and mild dilation and cortical atrophy
Acute renal failure.
what are the consequences of intermittent obstruction
Filtrate will pass back into the interstitum
Compress the medulla, impairing concentrating ability
Cortical atrophy, fall in renal filtration and renal failure.
OR
Continued glomerular filtration
Dilation of the pelvis and calyces
Cortical atrophy, fall in renal filtration and renal failure.
clinical features of acute bilateral obstruction.
pain, acute renal failure and anuria.
clinical features of chronic unilateral obstruction.
asymptomatic initially, if unresolved cortical atrophy and reduced renal function.
are males or females more likely to get renal calculi
males
pathogenesis of renal calculi
Either due to excess of substances which precipitate out e.g. Ca +.
OR
A change in the urine constituents causing precipitation of substances e.g. change in pH.
what is the most common type of renal stone
calcium
what causes excess calcium to be present.
hypercalcemia- bone disease, excess PTH and sacrodosis,
excessive absorption of intestinal calcium
inability to resorb tubular calcium
idiopathic
pathogenesis of striate stones formation
Urease producing bacterial infection (proteus)
Urease converts urea to ammonia
Cause a rise in urine pH.
Precipitation of magnesium ammonium phosphate salts
Large “staghorn” calculi.
pathogenesis of urate stones
Hyperuricaemia- gout, high cell turnover (leukaemia), idiopathic
pathogenesis of cystine stones
Occur in the presence of an inability of kidneys to reabsorb amino acids.
what investigations are carried out for renal caliculi
Non-contrast CT scanning
ultrasound (if CT not possible)
Intraveous urography.
sequalae to renal stones
obstruction, haematuria, infections, squamous metaplasia precursor.
what cell type are the majority of renal carcinomas
clear cell.
what are the risk factors of renal cell carcinoma
tobacco, obesity, hypertension, oestrogen’s, acquired cystic kidney disease
asbestos exposure.
define von hippel-Lindau syndrome.
most common renal cell carcinoma
pathogenesis of von hippel linadau syndromes
VHL gene required for breakdown of Hypoxia Inducible Factor-1 (HIF-1) oncogene
Loss of gene function causes cell growth and increased cell survival
Tumours develop in kidneys, blood vessels, pancreas
VHL mutations also commonly identified in clear cell RCC
clinical presentation of the von hippel liandau syndrome
local symptoms- haematuria, palpable abdominal mass, costovertebral pain/
paraneoplastic syndromes
paraneoplastic syndromes associated with renal cell carcinoma
Cushings- ACTH
Hypercalcaemia- parathyroid hormone related peptide.
Polycythemia- erthropoietin.
morphology of renal cell carcinoma
clear cell- well-defined yellow tumours, often with haemorrhagic areas, may extend to peripnephric fat or renal vein.
Papillary- more cystic, more likely to be multiple.
microscopy of a clear cell
Clear cells, Delicate vasculature, small bland nuclei
microscopy of papillary tumours
Cuboidal, foamy cells, surrounding fibro vascular cores often containing foamy macrophages or calcium.
urothelial cell carcinoma can affect what aspects of the urinary tract
Urothelial lining is over, ureter, bladder and the pelvis.
most common site for urothelial cell carcinoma
bladder
risk factors for urothelial cancer
age
gender- more common in males
carcinogens which cause urothelial cancer
smoking, aryl amines, cyclophosphamide, radiotherapy.
diagnosis of urothelial cancer
cytoscopy
clinical presentation of urothelial cancer
haematuria, urinary grequency, pain on urination, urinary tract obstruction
prognosis of urothelial cancer
recurrence common
out come depends on grade and stage
prognosis of renal clear cell carcinoma
5 years, but depends or whether the carcinoma is organ confined, tumour extends into perinephric fat and renal vein and whether it metastasises distally.
