UROLOGY Flashcards
Ddx acute onset flank pain, radiating to LIF
Older patient: AAA Renal colic Pyelonephritis Diverticulitis Bowel obstruction
Acute onset flank pain, radiating to LIF
- how do you investigate?
- Rule out AAA: CT AP in arterial phase
- CT KUB - determine size, location of stone; associated hydronephrosis or infection
- Standard AXR
- IV urogram
Consequences of renal calculi
Renal: haematuria; loin pain, pyelonephritis, hydronephrosis
Ureteric; haematuria; renal colic, hydrometer, ureteritis
Bladder; haematuria; suprapubic pain, cystitis, obstruction, bladder SCC
Urethral; haematuria; dysuria, urethritis, obstruction, pain on passing stone
Common sites of stones obstruction
- PUJ
- Pelvic brim level with common iliac bifurcation
- VUJ
Aetiology renal calculi:
ABNORMAL ANATOMY: horeshow kidney, VUR
INFECTION: proteus infection cause struvite stones
DEHYDRATION
METABOLIC DISEASE: hyperaemia, cysteinuria, hyperparathyroidism causing hypercalcaemia
STASIS: BPH and urethral stricture
MEDICATION: aspirin, diuretics, calcium based antacid, antiretrovirals
LIFESTYLE FACTORS: high sodium, high protein diets and high BMI
DIGESTIVE TRACT PATHOLOGY/SURGERY: resulting in chronic diarrhoea and alteration in calcium and water absorption (IBD, gastric bypass)
How does proteus infection cause stones?
Proteus cleaves urea to ammonium and carbon dioxide; alkalinising urine.
Increased pH levels predispose to stone formation as this reduced the solubility of phosphate
What are common compositions of renal calculi
- Calcium oxalate: 80%
- Calcium phosphate: 15%
- Struvite: 10%
- Urice acid 5%
- Cysteine 2%
What type of muscle lines the ureters?
Smooth muscle
What are the differences of smooth muscle and skeletal muscle
- Smooth muscles lines the wall of viscera; skeletal muscle is attached to tendon and bone
- Smooth muscle is under involuntary control; skeletal muscle is under voluntary control
- Calcium binding is smooth muscle is via calmodulin; in skeletal muscle it is via troponin
- Skeletal muscle has T-tubules and is arranged - exhibiting striations
What is the neurological basis for control of micturition
Normal bladder emptying is the result of parasympathetic stimulation and reciprocal sympathetic inhibition
Storage phase: sympathetic nervous system (S 1, 2, 3) relaxes detrusor muscle and contracts internal urethral sphincter
Micturition phase: parasympathetic nervous system (S 2,3,4) contracts bladder and relaxes internal urethral sphincter
NB. external urethral sphincter is under somatic (voluntary) control
How can causes of AKI be classified?
Pre-renal
Renal
Post-renal
Define acute kidney injury
Defined according to RIFLE criteria; biochemical diagnosis:
- Creatinine rise >26micromol/L in 48h
- Serum creatinine >1.5 fold from baseline within one week
- Urine output <0.5 ml/kg for >6 consecutive hours
What are indications for renal replacement therapy?
AEIOU +5
A - severe metabolic acidosis
E - refractory hyperkalaemia
I - intoxication
O - therapy resistant fluid overload
U - symptomatic uraemia (nausea, pruritus, malaise)
CKD 5
What types of RRT exist
RRT can be classified as continuous or intermittent:
Continuous:
- Haemofiltration: ITU-based; flow rate of blood is slow and solute removal is by convection
- Haemidialfiltration: combines convection and diffusion; it is the most effective at removing solutes
- Renal transplant
Intermittent:
1) Haemodialysis: in-centre or home heamodialysis. 3 sessions per week, each lasting ~4 hours. Rapid clearance of low molecular weight solutes by diffusion.
2) Peritoneal dialysis
What is dialysis disequilibrium syndrome?
This is an important complication of dialysis, characterised by the development of neurological signs and symptoms in a patient undergoing dialysis.
Caused by changes in osmolality from he clearance of substances such as urea.
Leads to cerebral oedema and can cause seizures.
