Kidney Flashcards
what is the most common make up of renal stones ?
80% are calcium
35% Oxalate
10% phosphate
35% mixed
what is the basis for formation of renal tract calculi ?
over-saturation of urine
due to high levels of purine and cystine in the blood
where are the 3 natural narrowings where ureteric stones are most likely to get stuck?
Pelviureteric junction (PUJ)
Vesicoureteric junction (VUJ)
Pelvic brim - where iliac vessels cross over the ureter in the pelvis
most common symptom of renal stones
unilateral flank pain
what are the presenting symptoms of renal stones ?
severe acute onset unilateral flank pain radiating from loin to groin
associated nausea and vomiting
haematuria present in 90% of cases - usually non-visible
rigors, fevers and lethargy if concurrent infection
what signs should you look out for to indicate concurrent infection in renal tract stones ?
lethargy
fever and rigors
differentials for renal tract stones ?
ruptured AAA
pyelonephritis
MSK pain
biliary pathology
bowel obstruction
investigations into suspected renal tract calculi?
urine dip - check for haematuria and infection
routine bloods
urate and calcium levels can aid diagnosis
imaging for renal tract calculi
gold standard = CT KUB
plain AXR can be used but not all stones are radio-opaque and so their use is limited
management of renal tract calculi
resus fluids if dehydrated
majority of stones pass spontaneously - so give analgesia and NSAIDs and advise plenty of fluids
if obstructive nephropathy is suspected a stent insertion or nephrostomy to relieve the pressure and remove the urine would be indicated - although this is a temporary fix
definitive management involves shock wave therapy to fragment the stones
complications with recurrent renal stones
cause scarring and loss of renal function - CKD
what is the concern with recurrent bladder stones?
chronic irritation of the bladder epithelium can predispose to the formation of a SCC bladder cancer
what is pyelonephritis?
inflammation of the kidney parenchyma and renal pelvis
most common causative organism in pyelonephritis
E.coli (80%)
risk factors for pyelonephritis
anything causing urinary retention e.g. BPH, obstructed urinary tract etc.
female urethra - shorter
indwelling catheter
immunocompromised - HIV, diabetes
sex
renal calculi
what is the classical triad of symptoms seen in a person with pyelonephritis
unilateral loin pain
nausea and vomiting
fever
often presents with LUTS aswell
what differential is important to rule out in a patient presenting with pyelonephritis
ruptured AAA - often patients present very unwell with tachycardia and hypotension
both of which, coupled with the loin pain, could indicate a ruptured AAA
investigations into suspected pyelonephritis
urinalysis - infection markers
routine bloods
b-hCG in women of childbearing age
renal USS to check for obstruction
CT KUB for further diagnosis
management for pyelonephritis
empirical antibiotics + IV fluids
analgesia + anti-emetics
what is emphysematous pyelonephritis
rare and severe form of acute pyelonephritis
caused by gas forming in and around the kidney
high mortality rate
fails to respond to empirical antibiotics
most common in diabetic patients as high glucose allows CO2 production from fermentation by enterobacteria
what is the most common form of renal cancer in adults?
renal cell carcinoma (RCC)
other than RCC what other forms of renal carcinoma are there?
TCC
nephroblastoma (children - Wilm’s tumour)
SCC - chronic inflammation
most common site of mets for RCC
liver
lung
brain
bone
risk factors for RCC
smoking
obesity
exposure to industrial carcinogens
dialysis
hypertension
