Renal + Genitourinary Flashcards
Define nephrolithiasis
- Renal stones
- Consists of crystal aggregates
- Stones form in collecting ducts
- May be deposited anywhere from renal pelvis -> urethra
Aetiology and risk factors of nephrolithiasis
- Dehydration
- Infection
- Hypercalcaemia/oxaluria/calciuria/uricaemia
- Primary renal disease
- Drugs
- Diuretics
- Antacids
- Corticosteroids
- Aspirin
- Vit C & D
- Diet
- Gout
State aetiology of calcium stone based nephrolithiasis
- Hyperparathyroidism
- Excess dietary Ca2+
- Idiopathic hypercalciuria (increased absorption in gut)
- Primary renal disease
- HYPEROXALURIA
- Dietary oxalate rich food (spinach, rhubarb, chocolate, tea)
- Low dietary Ca2+
Aetiology of infection induced stones
- UTI organism hydrolyse urea -> ammonium hydroxide
- Ammonium ions + alkalinity -> stone formation
Aetiology of cystine stones
- Cystinuria - autosomal recessive condition -> affects cysteine in epithelial cells of renal tubules
- Excessive urinary excretion and formation of cysteine stones
Clinical presentation of renal colic
- Rapid onset
- Excruciating ureteric spasm (writhing in pain)
- Loin to groin pain in waves
- Cannot lie still (differentiates from peritonitis)
Differential diagnosis of renal colic
- Vascular accident (AAA)
- Bowel pathology
- Ectopic pregnancy or ovarian cyst torsion
- Testicular torsion
Diagnosis of renal stones/colic
- FIRST LINE
- Kidney Ureter Bladder X-ray
- GOLD STANDARD
- Non-contrast CT of Kidney Ureter Bladder (KUB)
Treatment of renal stones/colic
- Strong analgesic for colic (IV DICLOFENAC)
- Antibiotics if infection
- Antiemetics for vomiting
- Medical expulsion therapy
- Oral NIFEDIPINE or Oral TAMSULOSIN to promote expulsion and reduce analgesia use
- Extracorporeal Shockwave Lithotripsy (ESWL) - ultrasound to fragment stones
- Endoscopy with laser for larg stones
- Percutaneous Nephrolithotomy (PCNL) - keyhole surgery
Define AKI
- Abrupt sustained rise in serum urea and creatinine
- Rapid decline in GFR
- Failure to maintain fluid, electrolyte and acid-base homeostasis
Criteria for diagnosing AKI
- Rise in creatinine > 26 micromol/L in 48h
- Rise in creatinine > 1.5x baseline
- Urine output < 0.5mL/kg/h for more than 6 consecutive hours
Aetiology of AKI
- Ischaemia
- Sepsis
- Nephrotoxins
Clinical presentation of AKI
- Palpable bladder, kidneys, pelvic masses, rashes
- Oliguria (low urine output)
- Arrhythmia
- High urea symptoms
- fatigue, anorexia, N&V
- Oedema
Differential diagnosis of AKI
- AAA
- alcohol toxicity
- Ketoacidosis
- CKD
- Metabolic acidosis
Treatment of AKI
- PRE RENAL
- Correct volume loss
- Treat sepsis
- INTRINSIC RENAL
- Refer to nephrology
- POST RENAL
- Catheter
- If signs of obstruction; treat obstruction
- Stop nephrotoxic drugs
- NSAIDS
- ACEi
- Gentamicin
- Amphotericin
- Renal Replacement Therapy (RRT)
- Haemodialysis
- Haemofiltration
Define CKD
- Longstanding progressive impairment
- In renal function
- GFR < 60mL/min/1.73m2
- > 3months
Aetiology of CKD
- Diabetes mellitus T2>T1
- Hypertension
- Atherosclerotic renal vascular disease
- Polycystic kidney disease
- Tuberous sclerosis
Pathophysiology of CKD
- When nephrons fail, burden of filtration fall on remaining nephrons
- Remnant nephrons experience increased flow/nephron (hyperfiltration) as blood flow remains the same
- Nephrons adapt by: glomerular hypertrophy and reduced arteriolar resistance
- -> Increased flow, pressure and shear stress
- -> Cycle of raised intraglomerular capillary pressure and strain
- .˙. accelerates remnant nephron failure
- Therapy aims to inhibit Angiotensin II and proteinuria through ACEI and angiotensin receptor antagonists
Clinical presentation of CKD
- Serum urea and creatinine used to measure accumulation of metabolites
- Serum urea > 40mmol/L -> symptoms
- Anorexia + weight loss
- Insomnia
- Nocturia + polyuria
- Itching
- D+V
- Oedema
Differential diagnosis of CKD
- AKI
- history
- duration of symptoms
NORMOCHROMIC ANAEMIA
SMALL KIDNEYS
RENAL OSTEODYSTROPHY
—–> CKD
Diagnosis of CKD
- Urinalysis
- Haematuria
- Proteinuria
- Albumin:Creatinine (ACR)
- Protein:Creatinine (PCR)
- Serum biochem
- U+E, Bicarb, creatine
- Low eGFR
- Raised alkaline phosphatase
- Raised PTH
Treatment of CKD
- Treat reversible causes
- Obstruction
- Nephrotoxic drugs
- Smoking cessation
- Glucose + weight control
- Limit progression
- BP target = <130/80
- ACEi = RAMIPRIL
- Angiotensin receptor blocker = CANDESARTAN (preferred if diabetes present)
- Diuretics = oral BENDROFLUMETHIAZIDE
- CCB = VERAPAMIL
- BONE DISEASE
- PTH
- Phosphate restriction + binders = decrease gut absorption
- Vit D + Ca2+ supplements
- CVD
- Statins (cholesterol) = SIMVASTATIN
- Aspirin
- ACIDOSIS
- Systemic acidosis -> increased serum K+
- Treat = SODIUM BICARB
- OEDEMA = FUROSEMIDE
- Renal Replacement Therapy
Define pyelonephritis
- Infection of renal parenchyma and soft tissues of renal pelvis and upper ureter
- Caused by KEEPS
- Klebsiella spp.
- E.coli
- Enterococcus spp.
- Proteus spp.
- Staph spp.
Pathophysiology of pyelonephritis
- Infection from bacteria from patient’s own gut flora
- Commonly via ascending transurethral route
Clinical presentation of pyelonephritis
- Loin pain + fever + pyuria (pus in urine)
- Rigors
- N+V
Differential diagnosis of pyelonephritis
- Diverticulitis
- AAA
- Renal stones
- Cystitis
- Prostatitis
Diagnosis of pyelonephritis
- Tender loin on examination
- Urine dipstick
- Nitrites
- Leucocyte elastase
- Odour
- Protein
- MIDSTREAM URINE MICROSCOPY = GOLD STANDARD
Treatment of pyelonephritis
- Cranberry juice + fluids
- Analgesia
- Antibiotics
- Mild = CIPROFLOXACILLIN or CO-AMOXICLAV
- Severe = IV GENTAMICIN or IV CO-AMOXICLAV