Genitourinary Flashcards
what are the 3 classical locations for renal stones to get stuck?
- Ureteropelvic junction
- pelvic brim
- Ureterovesical junction
what are most renal stones made up of? give some other possible constituents
*calcium oxalate.
phosphate, urate, hydroxyapatite, mixed.
give 3 predisposing factors for renal stones
hypercalcaemia, sarcoidosis, hyperparathyroidism, high uric acid, UTI, PKD, loop diuretics, antacids
why do renal stones form?
form when normally soluble material supersaturates the urine.
must also overcome the inhibitors of crystal formation present in normal urine.
what causes calcium renal stones?
hypercalciuria, due to hypercalcaemia - due to e.g. hyperparathyroidism, excess dietary clacium, excessive bone resorption (prolonged immobilisation)
who are particularly at risk of uric acid stones?
those with clinical gout - hyperuricaemia.
those with ileostomies - loss of bicarbonate from GI secretions leads to acid urine, reducing solubility of uric acid.
how might frequent UTIs put you at risk of renal stones?
some infecting organisms produce urease
describe the pain of renal colic
excruciating spasms, ‘loin to groin’.
often with nausea, comes and goes in waves, restlessness, dysuria, desire but inability to void.
what is the best investigation to visualise renal stones with?
KUBXR (kidney, ureter + bladder) or spiral CT
what other investigations might you perform in renal colic?
urine dipstick - 90% +ve for blood.
MSU for MC&S.
24h urine for calcium, oxalate, urate, citrate sodium, creatinine, stone biochemistry
how would you treat a patient with renal stones?
analgesia - diclofenac.
if 5mm - shock wave lithotripsy - US waves shatter stone.
give some examples of steps to be taken to prevent recurrence of renal stones
drink plenty, normal dietary calcium intake, allopurinol for urate stones, pyridoxine for oxalate stones.
define hydronephrosis. what can it lead to?
dilatation of renal pelvis - compression and thinning of renal parenchyma - decrease in kidney size.
what happens to the urinary tract proximal to a point of obstruction?
dilates
give 3 possible causes of urinary tract obstruction
prostatic obstruction - hypertrophy or tumour.
gynaecological cancers.
hypercalcaemia.
caliculi (stones).
renal tubular acidosis.
primary hyperoxaluria.
medullary sponge kidney.
TB.
how would acute upper urinary tract obstruction present?
loin to groin pain.
superimposed infection ± loin tenderness.
enlarged kidney.
how would chronic upper urinary tract obstruction present?
flank pain, renal failure, superimposed infection, polyuria (due to impaired urine concentration).
how would acute lower urinary tract obstruction present?
severe suprapubic pain.
symptoms of bladder outflow obstruction.
distended, palpable bladder, dull to percussion.
how would chronic lower urinary tract obstruction present?
urinary frequency, hesitancy, poor stream, terminal dribbling, overflow incontinence.
distended palpable bladder.
how would you treat upper urinary tract obstruction?
nephrostomy or ureteric stent.
alpha blockers - decrease ureteric spasm, help with stent pain.
how would you treat lower urinary tract obstruction?
urethral/suprapubic catheter.
treat underlying cause.
possible large diuresis on relief of obstruction - watch for salt loss!
give 2 pre-renal causes of AKI
renal hypoperfusion, sepsis, CCF, cirrhosis, renal artery stenosis, NSAIDs, ACE inhibitors
give 2 renal causes of AKI
acute tubular necrosis, PKD, SLE, renal cell carcinoma, myeloma, diabetic nephropathy, drugs, vasculitis, thrombus, HUS, TTP, infections.
give 2 post-renal causes of AKI
urinary tract obstruction by stones/clots, blocked catheter, retroperitoneal fibrosis, benign prostatic hypertrophy/prostatic carcinoma