Genitourinary Flashcards
What is nephrolithiasis
kidney stones
what are kidney stones made up of
calcium oxalate stones
where are kidney stones deposited
in the collecting duct
where can kidney stones be deposited
anywhere in the renal pelvis to the urethra
what are 90% of the kidney stones in the form of
radio opaque stones
other than radio opaque stones what other types of kidney stones are there
struvite
calcium phosphate
uric acid
cysteine
what are risk factors of nephrolithiasis
chronic dehydration
kidney inherited disease
hyperPTH (hypercacaemia)
UTIs
history of previous renal stones
what is the pathophysiology of nephrolithiasis
there is an excess of solute in the collecting ducts which causes super saturated urine. This favours crystalisation. The stones forms then cause regular outflow obstruction and hydronephrosis
how do you treat hydronephrosis
surgical decompression ASAP
what does obstruction of regular renal outflow cause
dilation and obstruction of the renal pelvis, increasing damage and infection risk
what is the presentation of nephrolithiasis
loin to groin pain that is colicky - peristaltic waves
the patient cant lie still
haematuria
dysuria
can have a fever is a suprarenal infection is present
what is a differential diagnosis for nephrolithiasis
peritonitis - same symptoms except there is rigidity
how do you diagnose nephrolithiasis
1st line = Kidney, ureters, bladder X-RAY (80% specific)
GOLD = CT kidney, ureters, bladder (99% specific) and therefore diagnostic
bloods: FBC, U&E and urine dipstick
how do you treat nephrolithiasis
if symptomatic = hydrate, analgesia (didofenac) IV for severe pain
Abx if UTI present (gentamycin)
Stones normally pass spontaneously if small enough (<5mm)
elective surgical Tx is too big to pass and causing pain
how do you surgically remove a kidney stone
Endoscopic sound wave Lithotripsy
Percutaneous nephrolithotomy (keyhole)
what is acute kidney injury
Abrupt decline in kidney infection (hrs to days) characterised by an increase in serum creatinine and urea and a decreased urine output
what is the classification of acute kidney injury
KDIGO
Serum creatinine increase 26umol/L within 48hrs OR 1.5X baseline in 7 days
Urine output <0.5ml/kg/hr for 6hrs consecutive
how do you stage acute kidney injury
use AKIN
stage 1, 2, 3, and the higher the stage the reduced likelihood of kidney injury
what are the three causes of acute kidney injury
pre-renal
renal
post-renal
what are the renal causes acute kidney injury
nephron and parenchyma damage
- tubular - acute tubular nephrosis
- interstitial cell death - fever, rashes eosinophilia
- glomerular
- toxins (sepsis)
what are pre-renal causes of AKI
Hypoperfusion
total body - decreased cardiac output (shock)
liver failure - hepatorenal syndrome
Renal artery stenosis or blockage
drugs - NSAIDs, ACE-i (decrease GFR)
IV contrast
what are causes of post renal AKI
obstructive uropathy
stones
BPH - common in elderly men
Drugs - anticholinergics, CCBc
Occluded indwelling
what are risk factors for AKI
increased age, comorbidities, hypovolemia of any cause, nephrotoxicity drugs, decreased blood filtration and urine output
What is the pathophysiology of acute kidney injury
there is an accumulation of usually excreted substances
- K+ causing arrhythmias
- Urea causes pruritis, uremic frost, confusion if severe
- fluid causes oedema
- H+ causes acidosis