Urology: Urinary Stones/Renal Colic Flashcards
what is urolithiasis?
the formation of stony things within the urinary tract
metabolic cause of urolithiasis
- hyperparathyroidism
- idiopathic hypercalcuria
- disseminated malignancy
- hypervitaminosis D
- sarcoidosis
- hyperthyroidism
- cystinuria
- hyperoxaluria
- xanthinuria
- hyperuricuria
- renal tubular acidosis
- primary kidney disease
- drugs
what type of calculous disease is common in developed countries?
upper urinary tract calculi
aetiology of calculous disease
- secondary to dehydration
- infection
- anatomical malformations
- metabolic disorders
types of calculi
- calcium oxalate
- phosphate
- urate
- cystine
- xanthine and pruvate
why are calcium oxalate stones important?
- they are the most common type of stone
- they have sharp projections
- cause bleeding and they themselves are black due to altered blood on their surface
which type of stone causes staghorn stones?
phosphate/struvite stones
signs and symptoms of renal stones
- continuous loin pain
- colic (if the stone becomes lodged at the PUJ)
- microscopic haematuria
- might have associated infection
signs and symptoms of ureteric stones
- colicky pain radiating from loin to groin
- sweatiness
- restlessness
- naseous
- vomiting
- microscopic haematuria
- might have associated infection
investigations for calculous disease
- urine dipstick: microscopic haematuria and possible infection
- MSSU for C&S
- U&E
- FBC
- CRP
- CTKUB w/o contrast
- KUB radiograph
- USS (hydronephrosis)
- IVU
- serum Ca, phosphate, uric acid
- 24h urine for Ca, phosphate, oxalate, urate, cystine and xanthine
treatment of an acute episode of renal calculi
- analgesia (may require opiates)
- antiemetic
- increased fluids
- collect and sieve out calculi for analysis
- IV antibiotics, if infection
- decompression if obstruction is present - done by percutaneous nephrostomy or ureteral stent
how can you remove a stone?
- it can be passed through urine if the stone is <4mm, maybe if <6mm
- > 6mm have to be removed
- medical explusive therapy: nifedipine or beta-blockers
- ureteroscopy and fragmentation done by lase, ultraspound or electro-hydraulic intracorporeal lithotripsy
how to prevent recurrent renal/bladder calculi?
- good fluid intake: 2-3L/day
- reduced Ca intake
- treat UTI promptly
- using Na2CO3 to alkalinise the urine in case of cystine and urate stone
- if there is uric stone: allopurinol
- oxalate stone: reduce oxalate intake
where are bladder calculi common?
developing countries
symptoms of bladder calculi
- dull suprapubic discomfort
- dysuria
- difficulty initiating urination
- strangury
treatment of bladder calculi
- always intervene
- <5cm: removed cystoscopically after crushing/fragmenting them
- > 5cm: suprapubic cystoscopy
where are the calculi more likely to lodge?
- pelviureteric junction
- pelvic brim
- vesicoureteric junction
what is calculous disease associated to?
- ESKD
- bone diseases
- hypertension
- myocardial infarction
causes of hypercalcaemia
- primary hyperparathyroidism
- vitamin D ingestion
- sarcoidosis
causes of hypercalcuria
- hypercalcaemia
- excessive dietary intake of Ca
- excessive resorption of Ca from the skeleton, such as occurs with prolonged immobilisation or weightlessness
- idiopathic hypercalcuria
causes of hyperoxaluria
- genetic (alanine-glyoxylate aminotransferase deficiency and gloxylate reductase hydroxypyruvate reductase deficiency) - in these cases, CKD develops early on and a liver transplant is needed to cure the metabolic defect
- excess ingestion high in oxalate
- dietary calcium restriction
- GI disease and increased absorption of oxalate in the colon
causes of hyperuricaemia
- idiopathic gout
- myeloproliferative disorders
- dehydration can cause these to form stones
drugs associated with stone formation
- loop diuretics
- antacids
- glucocorticoids
- theophylline
- vitamin C and D
- acetazolamide
- thiazide
- salicylates
differential diagnosis to renal stones
- acute appendicitis
- diverticulitis
- salpingitis
complications of renal stones
- obstructing urinary flow
- infection
- local tissue damage
- decreased renal function
- renal failure
what should you look for in a general inspection for renal calculi?
- corneal or conjunctival calcification
- gouty tophi
- arthritis
- features of sarcoidosis
indications for urgent stone removal
- obstruction
- infection
- persistent and recurrent pain
- urosepsis
differential diagnosi of calcification on plain AXR
- renal stones
- calcified mesenteric glands
- gallstones
- faecolith
- aortic aneurysm
