MedEd Histo 2 Flashcards
what is AKI
acute decline in renal function leading to fall in urine output
how is AKI captured in clinical setting
rise in creatinine / urea seen on U&Es
what is CKD
decreased kidney function or kidney damage, present for more than 3 months
how is CKD captured in clinical setting
fall in eGFR
normal eGFR
> 90
eGFR of each stage of kidney disease
1 = >90 (normal)
2 = 60 - 89 (mild)
3A = 45 - 59 (mod)
3B = 30 - 44 (mod)
4 = 15 - 29 (severe)
5 = <15 (ESRF)
2 most common causes of CKD
DM
HTN
other causes of CKD except DM and HTN
ADPKD (PCKD)
untreated AKI
- pyelonephritis
- ATN
- obstruction
how do categorise AKI
pre renal
renal
post renal
general cause of pre renal AKI
decreased blood flow to kidneys
causes of pre renal AKI
hypovolaemia
sepsis
CCF
renal artery stenosis
ACEi
general cause of renal AKI
direct damage to nephrons
causes of renal AKI
ischaemia
nephrotoxins
GN
interstitial nephritis
hepatorenal syndrome
HUS / ITP
general cause of post renal AKI
physical blockage to outflow
causes of post renal AKI
stones
tumours
prostate problems
blocked catheter
of the 3, which type of AKI is the most to least common
most common = pre renal
2nd = post renal
3rd = renal
what diseases affect the glomerulus
nephrotic and nephritic syndromes
name 4 nephrotic syndromes
minimal change
membranous
FSGS
secondary causes
name 5 nephritic syndromes
IgA vasculitis
post strep GN
Alports syndrome
benign familial haematuria
rapidly progressive GN - goodpastures, pauci immune, immune complexes
name 2 conditions which can affect BVs of kidney
HUS
TTP
name 2 tubule disorders
acute tubular necrosis
acute interstitial nephritis
what is mesangium
connective tissue (ESM) between capillaries in kidneys
what cells actually do the filtering in kidney
podocytes
triad of nephrotic syndrome
peripheral oedema
proteinuria
low serum albumin
define proteinuria
3g/day or PCR >300mg
what other 2 associated features often come with nephrotic syndrome
increased cholesterol
increased clotting tendency
what is the actual issue in nephrotic syndromes
issue with podocytes which form the filtration barrier
treatment of nephrotic syndromes
steroids
who gets minimal change disease
kids
Ix of minimal change disease
light microscopy
electron microscopy
immunoflurescence
what does light microscopy / immunoflurescnce of minimal change disease show
NOTHING
what does electron microscopy of minimal change disease show
loss of podocyte foot processes
tx and prognosis of minimal change disease
steroids (prednisolone) - very good response
what does immunoflurescence look for
immune complexes
who gets membranous GN
adults
histology of membranous GN
diffuse basement membrane thickening
what can you see on EM of membranous GN
spikey immune complexes deposited
what can you see on immunoflurescence of membranous GN
immune complexes across all the BM
tx and prognosis of membranous GN
poor response to steroids
2 associations of membranous GN
SLE
anti phospholipase a2 ABs
what is FSGS
focal segmented glomerulonephritis
characteristic finding of FSGS
only SOME parts of kidney affected (focal)
who gets FSGS
adults
histology of FSGS
focal and segmental scarring
EM of FSGS
loss of foot processes
immunoflurescence of FSGS and why
NOTHING - no immune complexes involved
steroid response to FSGS
not great but not as bad as membranous
secondary causes of nephrotic syndromes
DM
amyloidosis
buzzword for DM causing nephrotic syndrome
Kimmelsteil Wilson nodules
buzzword for amyloidosis
apple green birefringence with Congo red stain
2 types of amyloidosis & what they are
AA (chronic inflam eg RA)
AL (light chains -> MM)
triad of nephritic syndrome
HTN
haematuria
peripheral oedema
what do you see in urine of nephritic syndrome
red cell cast
what is the actual problem with nephritic syndrome
large proteins / immune complexes causing damage to delicate kidney BVs
what is the commonest cause of GN worldwide
IgA nephropathy
what preceeds IgA nephropathy
group A strep infection
how long after strep infection do you get IgA nephropathy
1-2 days
what is the problem in IgA nephropathy
deposition of IgA immune complexes within glomeruli
immunoflurescence of IgA nephropathy
IGA immune deposits in MESANGIUM
what is the 1/3rds rule with IgA nephropathy
1/3 get better
1/3 get CKD
1/3 need dialysis
difference between IgA nephropathy and post strep GN presentation
same Sx but post strep GN occurs 1-3 WEEKS after group A strep, but IgA nephropathy is 1-2 days
what is the problem in post strep GN
antigen mimicry and immune complex deposition
2 blood results seen in post strep GN
reduced c3
raised anti streptolysin O titre
immunoflurescence of post strep GN
granular IgG deposits in BASEMENT MEMBRANE
mx of post strep GN
supportive
name cresentic (rapidly progressive) GN
goodpastures
immune complex mediated
pauci-immune (ANCA-associated ie vasculitis)
what are cresentic (rapidly progressive) GN
most aggressive type of GN, causing renal failure in weeks
what is characteristic of cresentic (rapidly progressive) GNs on histology
severity and presence of crescents (macrophages in Bowman’s space)
buzzword for goodpastures
anti glomerular BM ABs
what does histology of goodpastures show
crescents
what does immunoflurescence of goodpastures show
linear deposition of IgG in GBM
sx of goodpastures
nephritic syndrome
pulmonary haemorrhage
causes of immune complex mediated GN
SLE
IgA nephropathy
post infectious
HSP
histology of immune complex mediated GN
crescents
immunoflurescence of immune mediated GN
bumpy deposition of immune complexes in GBM or mesangium
name 2 pauci-immune / ANCA associated GNs
granulomatosis with polyangiitis
eosinophilic granulomatosis with polyangiitis
buzzword for granulomatosis with polyangiitis
cANCA
buzzword for eosinophilic granulomatosis with polyangiitis
pANCA
where do pauci-immune GNs effect
vasculitis affecting small micro blood vessels
immunoflurescence of pauci-immune GN
no / scanty immune complexes
–> this one isnt immune complex mediated
sx of pauci-immune GN
skin rashes
pulmonary haemorrhage
nephritic syndrome
what is alports syndrome
hereditary cause of CKD
how is alports inherited
X linked (affects boys)
what is the defect in alports
type 4 collagen problem
triad of alports sx
nephritic syndrome
bilateral sensorineural deafness
lens dislocation