Nephrology & Urology Flashcards
Normal PaCO2
35-45 mmHg
Normal PaO2
85%
Normal HCO3
22-32 mmol/L
Normal PH
7.40-7.45
urinary urgency + urinary frequency + nocturia
Overactive bladder
Peaked T-waves are seen in lead V2,V3,V4 and V5 + widening of QRS, decreased amplitude of P waves
hyperkalaemia
ACE inhibitors + spironolactone
Increased risk of hyperkalaemia
The combination of ACE inhibitors and spironolactone increases the risk of hyperkalemia due to their complementary mechanisms of action on the renin-angiotensin-aldosterone system (RAAS), both leading to reduced potassium excretion.
1. ACE Inhibitors: • ACE inhibitors (e.g., lisinopril, enalapril) block the conversion of angiotensin I to angiotensin II. • Angiotensin II normally stimulates the release of aldosterone from the adrenal glands. • Aldosterone promotes sodium and water reabsorption in the kidneys and potassium excretion. • By inhibiting this pathway, ACE inhibitors lead to reduced aldosterone levels, resulting in decreased potassium excretion and potential hyperkalemia. 2. Spironolactone: • Spironolactone is an aldosterone antagonist, meaning it directly blocks the action of aldosterone on its receptors in the kidneys. • This further reduces sodium reabsorption and potassium excretion. • Since aldosterone’s effect is to promote potassium excretion, blocking it with spironolactone leads to retention of potassium.
Causes of hyperkalaemia
RAAMUN
– Renal failure.
– Metabolic acidosis.
– Addison’s disease.
– Use of aldosterone antagonists like spironolactone.
– ACEi.
– NSAIDs.
Renal stone recurrence management
- Increase water intake about 2.5 to 3 litres/day
- calcium-rich foods
- thiazide diuretics
- lewer oxalate-rich foods (Oxalate stones)
- Allopurinol
- urinary alkaliniser (potassium citrate)
Renal stones initial investigation
1st case: CT KUB
2nd recurrent: ultrasound + X-ray KUB
Renal stones diagnostic investigation
spiral CT KUB non-contrast
alkaline urine + “Staghorn calculi”
Struvite stones
Proteus pathogen renal stone
Struvite
-magnesium ammonium phosphate
Uric acid stone treatment
- Allopurinol
- urine alkalinization
Oxalate stone treatment
Renal stones in renal pelvis management
< 2.5cm: Extracorporeal lithotripsy
< 2.5cm: Percutaneous lithotripsy
Renal stones in ureter
Upper half < 1cm: Lithotripsy
Upper half: >1 cm: Lithotripsy or nephrolithotomy
Lower half < 1cm: Lithotripsy
Lower half > 1cm: Lithotripsy or endoscopy
Renal stones in bladder
< 3cm: Transurethral lithotomy
> 3cm: Cystotomy
Low potassium + hypertension
Investigations
Investigate serum aldosterone
Most common complication of radical prostatectomy
Erectile Dysfunction (ED)
Premature ejaculation treatment
1st line: SSRI (raises orgasm threshold)
main complication of retroperitoneal lymph node dissection (RPLND)
Retrograde ejaculation
most common complication of TURP
Urinary tract infection (UTI)
UTI requiring hospitalisation
any infant < than 3 months
- increased risk of urosepsis
Infant UTi treatment
- IV trimethoprim/gentamicin, benzyl penicillin
Erectile Dysfunction (ED) management
Initial :
- Optimise modifiable risk factors / related comorbidities (HTN, DM, diet/exercise etc)
- Treat reversible causes
(Low testosterone, Medication-induced erectile dysfunction, Psychogenic erectile dysfunction – consider referral to a therapist)
- Pharmacological/Surgical treatment
- 1st line: phosphodiesterase type 5 inhibitor (sildenafil)
- 2nd line: penile injections, vacuum erection devices, external shock wave lithotripsy
3rd line: penile prosthesis
polycystic kidney disease features
- Polyuria and nocturia
– Renal failure
– Hypertension
– Abdominal wall and inguinal hernias
– Colonic diverticulosis
– Hepatic cysts
– Subarachnoid or cerebral haemorrhage
– Cardiac anomalies including mitral valve prolapse
albuminuria in diabetes
first void spot specimen Urinary albumin to creatinine (ACR) ratio
URTI + proteinuria + haematuria + immediate onset
IgA nephropathy
IgA nephropathy treatment
Asymptomatic microscopic haematuria: 2 positive
UAs out of 3 in 2-3 weeks
Symptomatic: corticosteroids
URTI + proteinuria + haematuria + onset within weeks + facial oedema
Poststreptococcal glomerulonephritis (PSGN)
HIV px + taking indinavir + haematuria + loin pain
Indinavir induced nephrolithiasis
- Only detectable on US
- Remove/Change indinavir
onset within weeks + HIV hx + haematuria + proteinuria
Focal segmental glomerulosclerosis (FSGS)
HIV-associated nephropathy (HIVAN)
-Nephrotic range proteinuria
-Azotaemia
-Normal to large kidneys on ultrasound images
-Focal segmental glomerulosclerosis (FSGS)
shortened QTc interval on ECG
Severe hypercalcaemia
Dialysis indications
- Pericarditis or pleuritis (urgent indication).
- Progressive uraemic encephalopathy or neuropathy (confusion,
asterixis, myoclonus, wrist or foot drop, or, in severe cases, seizures (urgent indication). - A clinically significant bleeding diathesis attributable to uraemia (immediate indication).
- Persistent metabolic disturbances that are refractory to medical therapy (hyperkalemia, metabolic acidosis, hypercalcemia,hypocalcemia,
hyperphosphatemia) - Fluid overload refractory to diuretics
Dialysis metabolic abnormalities
- hyperphosphatemia
- Vitamin D deficiency
- hypocalcaemia
- secondary hyperparathyroidism
- hyperphosphataemia
Dialysis skeletal abnormalities
renal osteodystrophy:
- Osteomalacia
- osteosclerosis
- osteitis fibrosa cystica