Nephro: The Kidney in Systemic Disease Flashcards
why is renal involvement relevant in systemic disease?
- there is a worse prognosis if the kidneys are involved
- different treatment is needed if the kidneys are involved
- rarely the nature of systemic disease is only established by a renal biopsy
when should you suspect renal involvement in systemic disease?
- evidence of renal disease
- evidence of systemic disease
- both of the above have to correlate with each other
what is the most obvious abnormality in multiple myeloma
diminished renal function
indicators of renal disease
- abnormal renal function
- abnormal urinalysis (IMP)
- abnormal renal imaging
how is the renal structure in AKI?
renal size and anatomy are preserved
what happens if systemic disease equally affects both kidneys
use functional imaging like IVU, CT with contrast and DTPA scan
- can also be detected by blood tests
what renal test is always significant
a drop in eGFR (disease can also be present in a normal eGFR)
how does the eGFR vary between genders
females have a eGFR which is 15% less than in men
what can urinalysis show?
haematuria and proteinuria
what does urine microscopy show?
casts
what types of casts can be found on microscopy?
granular and hyaline casts may mean nothing
cellular casts are always bad
how do you quantify proteinuria?
- simple urinalysis
- ACR
- 24h urine collection
what is the dipstick sensitive to?
albumin
what does albuminuria indicate?
glomerular pathology
what will kidneys damaged by multiple myeloma show
- negative dipstick
- normal ACR
- elevated PCR
important things to get from a history
- other comorbidities
- symptoms related to multisystem disorders
- underlying malignancy
- is the patient at risk of being HepB, HepC or HIV positive?
what are features that suggest diabetic nephropathy?
- nephrotic-range proteinuria
- time between diagnosis of DM and DN is more than 5 years
- evidence of microvascular disease elsewhere like in the eyes and NS
- the condition is progressing at a slow rate
what does haematuria in a diabetic mean?
means that there is another renal problem apart from the DN
when would you do a renal biopsy?
when there are signs which are not linked with DN such as haematuria, cellular casts, rapid progression in disease or serological tests suggesting other systemic disease
risk factors for nephrosclerosis
- age
- HTN
- diabetes
examples of connective tissue disorders that affect the kidneys
- SLE
- RA
- mixed CT disease
examples of primary vasculitides that affect the kidneys
- microscopic polyangiitis
- wegeners granulomatosis
- churg strauss syndrome
- Henoch-Schonlein purpura
others disease that effect the kidneys
- Goodpasteur’s disease
- subacute bacterial endocarditis
- mixed essential cryoglobulinaemia
what are these systemic diseases with renal involvement have in common
- glomerular involvement
- presence of cellular casts
- rapidly progressive disease
- microscopic haematuria
