Renal Flashcards
Summarise AKI
Criteria:
Creat rise of either: >25 in 48 hrs, >50% in 7 days or <0.5ml/kg/hr for >6 hrs
RF:
Drugs: NSAIDs, ACE-i; CKD; DM; HF; LF; Age; Contrast medium
Causes:
Pre: Dehydrated, shock, HF
Renal: Drugs, intersistial nephritis, glomerulonephritis, acute tubular necrosis
Post: Obstruction e.g. stone, tumour, strictures, BPH
Ix:
U+E, FBC, Urinalysis, US for obstruction
Mx:
Stop nephrotoxic meds, IV fluids, relieve obstruction. If severe may need dialysis.
Complications: High K+, metabolic acidosis, fluid overload, uraemia (encephalopathy)
Summarise CKD
Pathophysiology: Kidney impairment –> Low active vit D —> low Ca and high PO4 –> secondary hyperparathyroidism –> Osteomalacia + scelrosis
Causes:
DM, age, htn, PKD, LF, Drugs, glomerulonephritis
Presentation:
Often incidental finding. May have: itching, loss appeitite, cramps, oedema, N+V, neuropathy, htn
Ix:
eGFR diagnoses (2 tests 3 months apart) - use U+E to do this
Proteinuria and haematuria on dipstick
Albumin: creatinine ratio (ACR)
Mx:
Manage causes + complications (Anaemia, bone disease, CVD, neuropathy, metabolic acidosis)
Refer if eGFR <30; ACR >70; uncontrolled htn
Special dietary advice about phosphate, sodium, potassium and water intake
ACE-i first line; EPO anaemia; bicarbonate for acidosis; Vit D + bisphosphonates for bone disease
Summarise Polycystic Kidney Disease
Pathophysiology: AR and AD inherited with AR being more severe and presenting in childhood
Presentation: Loin pain, masses, htn, berry aneurysms, cysts in liver, ovaries, spleens, MR, CVD, gross haematuria when cysts rupture, renal stones
Ix:
US kidneys + U+Es, BP
MRI angio brain for berry aneurysm
Mx: Tolvaptan!!! Slows progression Anti-htn Drain and give abx for infected cysts Dialysis + transplant late stage genetic counselling Avoid contact sports to stop cyst rupture Monitoring
Summarise Acute Tubular Necrisis
Pathophysiology: Death of epithelial cells of renal tubules - most common cause AKI
Causes: Toxins (Drugs, contrast), ischaemia (poor perfusion eg sepsis, hypovolaemia, dehydration)
Ix: Muddy brown casts on urinalysis
Mx: Supportive - remove toxin, treat cause, as per AKI
Summarise Renal Tubular Acidosis
Definition: Metbolic acidosis caused by pathology of tubules
Type 1: DCT doesn’t secrete H+. Get a hypokalaemia. (genetics, SLE, sjogrens, PBC, SCD, marfans). Mx with bicarbonate.
Type 2: Issue with PCT reabsorbing bicarbonate- fanconis
Type 3: Mix 1 and 2 - ignore!
Type 4:
Hypoaldosteronism (Addisons, ACE-i, spironolactone, ALE, DM, HIV)–> Aldosterone absorbs Na and secretes K so without it causes hyperkalaemia –> Ammonia is supressed by K and so get acidotic urine + kidney cant control pH as well
Mx: Hydrocortisone and bicarbonate
Summarise Haemolytic Uraemic Syndrome
Pathophysiology: E.coli 0157 shiga toxin causes clotting of small blood vessels –> use up platelets –> Clots chop up passing RBC –> Deposit in kidney. TRAID: Haemolytic anaemia, AKI + thrombocytopenia
RF: Loperamide and abx
Presentation:
Blood diarrhoea –> 5 days later:
Haematuria, oliguria, abdo pain, bruising, confusion, htn, pallor
Mx:
Emergency!
Dialysis, transfusion, anti-htn
Summarise Rhabdomyolysis
Pathophysiology: Death of muscle cells –> CK, myoglobin, K+ and PO4+–> AKI and cardiac arrest
RF: crush injury, prolonged immobility, excessive exercise, seizures
Presentation: Red-brown urine, Confusion, muscle aches, oedema, fatigue
Ix: CK, myoglobinurea, K+, ecg
Mx:
Fluids
Consider Mannitol or bicarbonate
mx hyperkalaemia
Summarise Glomerulonephritis
Nephritic Syndrome: (Haematuria, proteinuria, oedema, oliguia)
IgA Nephropathy
Membranous glomerulonephritis - histology shows IgG and complement deposits in Basement membrane
Post-strep gloemrulonephritis - young, post tonsillitis/ impetigo
Goodpasteurs - Anti-GBM Ab, have haemoptysis
Nephrotic Syndrome: (Proteinuria, hypoalbuminaemia, oedema, hypercholestrolaemia)
Minimal change disease - normal microscopy, urinalysis shows small molecular weight proteins and hylaline casts
Focal Segmental Glomeruloscelrosis - most common cause in adults
Mx: For all is with steroids and BP control, diuretics for oedema
