the importance of proteinuria W1 Flashcards
spelling?!!?!!!!
proteinuria (not urea)
what important proteins do the kidneys make
erythropoietin (epo)
active vitamin D
renin
function of erythropoietin
hormone which stimulates the bone marrow to produce red blood cells
what is proteinuria a cardinal sign of?
kidney disease
when should testing for proteinuria be carried out?
any routine medical consultation
oedema
part of care of patients with hypertension, diabetes mellitus etc
if a systemic disease is possible
oedema features
ascites (oedema in abdomen)
pleural effusions
what does colour coding on test strips show you when testing for proteinuria?
trace
1+
2+
3+
4+
what does 2+ proteins in urine imply
implies intrinsic renal disease and very unlikely to be explained by asymptomatic infection
why is the albumin/creatinine ratio used?
accurately correct for eg volume, concentration
albumin?
protein which doesn’t usually appear in the urine in significant quantities
units for albumin/creatinine ratio? what can this be performed on?
mg/mmol
performed on small urine sample taken any time of the day
what approximates the amount of albumin in 24 hours
ACR (albumin creatinine ratio) x10 approximates to mg of albumin in 24 hours
ACR levels meaning?
<3.5 is normal
3.5-30 = microalbuminuria
>30 = (macro)albuminuria
measurements of excretory renal function?
plasma/serum creatinine
estimated GFR (MDRD formula - sex, age, race, creatinine)
creatinine clearance (creatinine in blood compared to excreted but old fashioned)
isotope GFR (inject radioactive isotope, very formal)
what do different creatinine measures mean for different people?
if its high in elderly, female, slim then more of an indicator of low GFR than if its high in muscular, young, male as creatinine is a breakdown product of muscle.
what does the number of functioning nephrons decrease with? which ethnicities may have fewer nephrons?
number of functioning nephrons decreases with age
Black and Asian people may have fewer nephrons
congenital nephrotic syndrome?
massive leakage of protein into urine.
ascites
can be kept alive with dialysis
may need kidneys removed (will need dialysis, transplant)
what is congenital nephrotic syndrome due to
mutation in podocyte specific gene eg nephrin
asymptomatic 50 yr old man with ++ protein and ++ blood - investigations?
BP
test for diabetes
quantify proteinuria
check kidney function
renal ultrasound
renal biopsy?
what does the presence of blood and protein in the urine imply
glomerular disease - therefore urgent need to test excretory kidney function.
consider systemic diseases (eg vasculitis, lupus)
what does albuminuria imply in diabetes and hypertension
in diabetes - earliest feature of diabetic nephropathy
in hypertension - suggests primary renal cause
albuminuria and cardiovascular disease?
albuminuria is a potent independent cardiovascular risk factor in both diabetic and non-diabetic populations and aggressive management of cardiovascular risk is indicated.
16 year old female with recent onset of severe body swelling - investigations?
treatment?
BP
test for diabetes/other systemic diseases
quantify proteinuria
check kidney function
renal ultrasound
renal biopsy
treatment - corticosteroids, other drugs
nephrotic syndrome features?
oedema
heavy proteinuria
hypoalbuminaemia
nephrotic syndrome - features not included in definition but still clinically important?
thrombotic risk
propensity to infection
often severe hyperlipidaemia
what may/may not nephrotic syndrome be associated with
impairment of excretory kidney function
symptoms of nephrotic syndrome
severe lethargy
reduced exercise tolerance
nausea
loss of appetite
causes of nephrotic kidney syndrome
glomerulonephritis
diabetes
infections (hep B/C, malaria, HIV)
amyloid (deposition in glomeruli)
20 year old woman with short history of rash and painful small joints in both hands and feet.
+protein, +++blood
what does this indicate?
increased blood over protein indicates inflammation in glomerulus - glomerular nephritis
ANCA?
anti-neutrophil cytoplasm antibody
what does haematuria indicate?
haematuria, whether visible (macroscopic) or non-visible (microscopic) can be a sign of a serious systemic disease for which diagnosis and treatment is very urgent, whether or not there is also albuminuria
diseases where the glomerulus is damaged?
rare genetic/developmental disorders
diabetes mellitus
vascular disease/ischaemia/age
vasculitis (isolated/systemic)
inflammation of glomerulus itself (glomerulonephritis)
deposition diseases (eg amyloid, myeloma)
