Theme 4 Lecture 4: Renal pathology Flashcards
What does erythropoietin do?
stimulates erythrocyte production
What does renin control?
fluid balance and blood pressure regulation (RAAS)
What is the presentation of acute renal failure?
- unwell, rapid rise in creatinine and blood urea (which are estimators of renal function)
- occurs over a few days
What is the presentation of nephrotic syndrome?
oedema, proteinuria, hypoalbuminaemia, haematuria, hypertension, renal failure
What is chronic renal failure?
slow decline in renal function
What is the kidney divided into?
outer cortex, inner medulla, renal sinus
What is found in the renal cortex?
glomeruli and tubules
What are podocytes?
cells in the bowmann’s capsule in the kidneys that wrap around capillaries of the glomerulus
What is the name for the functional unit of the kidney?
nephron
Why does the glomerulus lie between afferent and efferent arterioles?
because arteries have muscles in the vessel wall so they are able to maintain the volume and pressure of blood flow to maintain the function of ultrafiltration
What does the nephron consist of?
proximal convoluted tubule, loop of henle, distal convoluted tubule and collecting duct
What 3 factors can contribute to the narrowing of renal vessels
- hypertension
- diabetes
- atheroma e.g renal artery stenosis
What are the two conditions that can arise from vascular damage in the kidney?
- Thrombotic microangiopathy
- thrombi in capillaries/ arterioles
- endothelial damage by bacterial toxins, drugs, complement or clotting system abnormalities
e. g haemolytic uraemic syndrome - Vasculitis
- acute/chronic vessel wall inflammation with lumen obliteration
- various types affect different calibre vessels
e. g wegener’s granulomatosis
What are the immunological causes of glomerular damage?
- circulating immune complexes deposit in glomerulus e.g SLE/ IgA nephropathy
- circulating antigens deposit in glomerulus
- antibodies to BM/ glomerular components e.g goodpastures syndrome
How does immunological damage of the basement membrane lead to glomerular damage?
- immune complexes/antigens or antibodies deposit in glomerulus
- complement activation
- neutrophil activation
- reactive oxygen species
- clotting factors
- glomerular damage
What are the non-immunological causes of glomerular damage?
- endothelial injury e.g vasculitis, HTN, clotting disorders, HUS
- altered basement membrane e.g DM hyperglycaemia
- abnormal BM or podocytes due to inherited disease e.g alport disease
- abnormal protein deposition (amyloid) impair function e.g RA
Which ischaemic causes cause reduced perfusion and therefore tubular damage?
- hypotension e.g shock
- vessel damage e.g vasculitis, HTN
- glomerular damage
What are the toxic causes of tubular damage
-direct toxins
-hypersensitivity reactions - drugs
-crystal deposits e.g urate
-abnormal protein deposition e.g Ig’s
all of these cause inflammation of the tubular interstitial compartment
Which toxins can directly cause tubular damage?
- drugs e.g antibiotics, NSAIDs, ACEi, diuretics
- contrast medium
- organic solvents
- heavy metals
- ethylene glycol
- pesticides
What are some diseases of the kidney?
- Membranous nephropathy (primary/secondary)
- FSGS (primary/secondary)
- Mesangiocapillary glomerulonephritis minimal change disease
- Post-infective glomerulonephritis
- Anti-GBM disease
- IgA nephropathy
- Henoch-Schönlein purpura
- Lupus nephritis (in SLE)
What is mimimal change disease?
kidney disease where lots of protein lost in urine
What does crescentic mean?
rapidly progressive
What are the synonyms of glomerulonephritis?
nephropathy
glumerulopathy
nephritis
What are the features of nephrotic syndrome?
- damage to the glomerulus
- proteinuria (>3g in 24h)
- oedema
- hypoalbuminaemia
- +/- hypertension
- +/- hyperlipidaemia
- complications - infection, thrombosis
