Flashcards in Genitourinary Deck (378)
How is circulating active vitamin D produced?
by 1a hydroxylation in the proximal tubule
How does CKD affect vitamin D production?
increased FGF-23 production which inhibits 1a-hydroxylation, inhibiting vitamin D production
Function of calcitrol?
increases calcium and phosphate absorption from the gut and suppresses the parathyroid hormone
What causes calcitrol deficiency?
advanced CKD, leading to secondary hyperparathyroidism
What nerves drive detrusor contraction?
PNS s3-5 (cholegenic)
What nerves inhibit detrusor contraction?
SNS t10-l2 (noradenergic)
How much fluid can a full bladder hold?
How much is in an empty bladder?
Who is more likely to become incontinent and why?
women, due to a shorted urether, so less resistance and higher pressure
What is acute renal failure?
a reversible decrease in GFR caused by damage to the kidneys, leading to a rise in serum urea and creatinine and loss of normal water and solute homeostasis
Main causes of acute renal failure?
pre renal (40-70%) - failure of cardiac/liver/skin/vascular, sepsis, infection, haemorrhage, thrombosis
intrarenal (10-15%) - renal vascular, glomerulinephritis, nephrotic syndrome, nephrotoxis drugs, microangiopathy, hypertension, inflammation, autoimmune disease
post renal (10-25%) - urinary tract obsturction, stones, tumour, prostatic hypertrophy, extrinsic compression
Stages of acute renal failure with serum creatinine and urine output?
early - creatinine >26.5umol/L or 1.5-2xrise - urine output 6h
moderate - creatinine 2-3x baseline - urine output 12h
severe - creatinine >3x baseline or >350u/mol/L or start RRT - urine output 24h or >12h anaemia
In who is acute renal failure common?
hospital admissions, elderly, critically ill
Mortality of acute renal failure?
Risk factors of acute renal failure?
>75yrs, CKD, HF, Chronic liver disease, diabetes, new drugs, spesis, poor fluid intake, history of urinary symptoms, blockage of urinary tract, dehydrated, infection, aminoglycosides
Most common cause of acute renal failure and types of this?
acute glomerularnephritis - from SLE, erythromyetosis
acute tubular necrosis (50% of AKI)
acute interstitial nephritis - in allergic reactions and infection
Pathophysiology of acute renal failure?
vascular change causes inflammation and tubular change causes back leakage of urine
What do investigations show in acute renal failure?
decrease GFR and urine output, increase nitrogenous waste in blood (urea, creatinine)
apoptosis, loss of adhesion
pericardial rub, suprapubic percussion dull
CT, CXR, avoid imaging with contrast, US (priotity if anuric)
Symptoms of acute renal failure?
lethargy, nausea, anorexia, itch, confusion, rash, joint pain, red eyes, nasal stiffness, GI bleeding, haemoptysis, reduced urine output, impaired platelet function, abdominal flank pain, oedeme, pruritis
Treatment of acute renal failure?
treat underlying cause, stop nephrotoxins, fluid, electrolytes, improve perfusion, restrict sodium and potassium, prevent pressure sores, antibiotics, dialysis, nutrition, sequele, prevent further complications, MDT, catheter if obstruction, percutanous nephrostomy, prevent ischemic renal injurt
When should you use dialysis in acute renal failure?
electrolyte abnormalities e.g. K
ingestions of toxins - salicylates, methanol, barbityrates
overload of fluid
uremic symptoms e.g. pericarditis
What is the classification of acute renal failure?
risk, injury, failure, loss, end stage
When would you do a urology referral in acute renal failure?
infected or obstructed urinary tract, renal stone, urological malignancy, renal trauma, frank haematuria,
Management of pulmonary oedema?
o2, diureticsm nitrates, opiates, venesection, haemodialysis, ventilatory support
What complications can acute renal failure lead to?
metabolic acidosis, hyperkalaemiam hyperphosphataema, pulmonary oedema
What does prognosis of acute renal failure depend on?
underlying cause, most common cause of death is sepsis from impaired immune defence from uaemia, malnutrition or dialysis//catheters
it is reversible
cortical necrosis can heal with scar tissues, tubule regenerate
What can you use to determine pre renal or intra renal acute renal failure?
urine specific gravity and urine osmolarity are higher in pre renal, urine sodium and fractional excretion of sodium are less in pre renal
What is the onset like in post renal AKI?
insidious rather than acute
What are the 2 phases in acute tubular necrosis?
initialoliguric phase from decrease GFR, microvascular vasoconstriction, ischemia, but then tubular cells can regenerate , reversing it
diuresis during recovery phase - improved GFR but still impaired tubular reabsorpton