Renal Flashcards
Renal
What are the functions of the kidneys?
Removal of waste products/toxins Balancing of electrolytes Stabilising acid-base status Maintaining fluid balance Activating Vit D Stimulating erythropoiesis Maintaining blood pressure
What is an acute kidney injury?
A rapid reduction of kidney function, leading to an inability to maintain fluid, electrolyte and acid-base homeostasis
What are the 3 types of AKIs?
Pre-renal
Renal
Post-renal
What are the causes of pre-renal AKI?
Hypovolaemia/tension
- Sepsis
- Major haemorrhage
- Vomiting/diarrhoea
- Congestive HF
Renal-specific
-RAS/embolus
Drugs eg ACEi, NSAIDs
What are the signs and symptoms of pre-renal AKI?
Tachycardia
Hypotension
Increased capillary refill time
Clinically dry (decreased turgor, absent JVP, dry mucous membranes)
What are the causes of post-renal AKI?
Urinary tract obstruction
- Stones
- Clots
- Blocked catheter
Mural
- BPH
- Malignancy of urinary tract
- Strictures
Extrinsic compression
- Pelvic malignancy
- Retroperitoneal fibrosis
What are the signs and symptoms of post-renal AKI?
Hx of urgency, frequency, or hesitancy
Flank pain +/- haematuria
Distended, palpable bladder if LUTO
What are the causes of renal AKI?
Acute tubular necrosis 2ary to:
- ischaemia (pre-renal)
- nephrotoxic damage
- rhabdomyolysis
Glomerulonephritis
Acute interstitial nephritis (classically NSAIDs)
Vasculitis
What are the signs and symptoms of renal AKI?
Hx of nephrotoxic drug/long lie/crush injury Rash, petechiae, ecchymoses Nephritic syndrome (oedeoma, proteinuria, microscopic haematuria)
What are the investigations for AKI?
Urinalysis- protein, blood, high specific gravity, cellular casts
U+E- raised creatinine, urea, potassium
VBG- metabolic acidosis
Renal US- unilateral vs bilateral dilated calyces
ECG- signs of hyperkalaemia
What is the management for pre-renal AKI?
Correct volume depletion
Haemofiltration if indicated
What is the management for post-renal AKI?
Urinary catheterisation
Urology referral
Haemofiltration if indicated
What is the management for renal AKI?
Treat underlying course
Supporative care
Haemofiltration if indicated
What is chronic renal failure?
Impaired renal function for >3months, either abnormal structure/function, or GFR <60ml/min
How many stages of chronic renal failure are there?
Stage 1 >90 Stage 2 60-89 Stage 3a 45-59 Stage 3b 30-44 Stage 4 15-29 Stage 5 <15 End stage renal failure
What are some causes of chronic renal failure?
Diabetes mellitus Hypertension Chronic inflammation Glomerulonephritis Vasculitis Myeloma/myeloidosis Pyelonephritis Polycystic kidney disease Renal artery stenosis
What are the signs and symptoms of chronic renal failure?
Uraemia- nausea, vomiting, pruritus, yellow skin
Uraemia in extremis- encephalopathy and pericarditis
Hyperkalaemia- arrhythmia
Metabolic acidosis- tachypnoea, confusion
Oedema- periorbital, peripheral, pulmonary
Vit D def- osteomalacia, hypocalaemia
Anaemia- fatigue, breathlessness, pallor, hypertension
What are the investigations for chronic renal disease?
Urinalysis
-haematuria, proteinuria, microalbuminuria
Bloods
-low Hb, raised creatinine/urea, raised K, dec Ca, raised PO4, raised ALP, raised PTH
Imaging
-USS kidneys, shrunk in CKD (unless ADPKD, amyloidosis, myeloma)
Histology
-Renal biopsy
What is glomerulonephritis?
Diseases characterised by immune mediated inflammatory changes in the glomerular capillaries and basement membrane.
What are the two types of glomerulonephritides?
Nephritic syndrome (aka proliferative GN) Nephrotic syndrome (aka non-proliferative GN)
What is nephritic syndrome?
Inflammation of the glomerulus, causing haematuria
What is nephrotic syndrome?
Proteinuria due to podocyte pathology
What are you looking for in nephritic syndrome?
Haematuria +/- RBC casts
Proteinuria
Hypertension
Decreased GFR
What are you looking for in nephrotic syndrome?
Heavy proteinuria (>3.5g/24h)
Hypoalbuminaemia
Oedema
Hyperlipidaemia
What are the types of proliferative glomerulonephritis?
IgA nephropathy
Post-streptococcal GN
Rapidly progressive GN