genitourinary Flashcards
wtf is acute kidney injury? + complications
acute drop in kidney function diagnosed measuring increased serum creatinine (waste product produced by muscles and filtered by kidneys into urine)
NICE Criteria:
Rise in creatinine ≥ 25 micromol/L in 48 hours
Rise in creatinine of ≥ 50% in 7 days
Urine output of < 0.5ml/kg/hour for > 6 hours
complications -
hyperkalaemia (kidney not filtering out into urine)
fluid overload, heart failure, pulmonary oedema
metabolic acidosis
uraemia (high urea) - can lead to encephalopathy or pericarditis
risks and causes of an AKI?
RF:
chronic kidney disease, heart failure, diabetes, liver disease, older age (65+), cognitive impairment, use of contrast medium eg. during CT scans, nephrotoxic medications eg. NSAIDS and ACE inhibitors
Causes:
PRE-RENAL =
most common cause, due to inadequate blood supply to kidneys which reduces filtration of blood (which may be due to dehydration, hypotension/shock, heart failure)
RENAL=
intrinsic disease in kidney has lead to reduced filtration of blood (which may be due to glomerulonephritis, interstitial nephritis, acute tubular necrosis)
POST-RENAL =
caused by obstruction to the outflow of urine causing a back-pressure into kidney hence reduced kidney function = obstructive uropathy!
(which may be caused by kidney stones, masses such as cancer in abdomen/pelvis, ureter or uretral strictures (narrowing), enlarged prostate/prostate cancer)
manage AKI?
prevention =
avoid nephrotoxic meds, adequate fluid input for unwell patients (IV)
treatment =
- fluid rehydration with IV (pre-renal)
- stop nephrotoxic meds such as NSAIDS and antihypertensives like ACE inhib (bc they reduce filtration pressure)
- relieve obstruction eg. insert catheter if enlarged prostate
may need dialysis in severe cases
wtf are kidney stones? + types
also known as renal calculi/colic, urolithiasis and nephrolithiasis
hard stones that form in renal pelvis
may be asymptomatic until they irritate/cause obstruction in ureters, commonly get stuck at the vesico-ureteric junction
types:
calcium stones =
- most common (80%)
- raised serum calcium/hypercalcaemia and low urine output
- 2 types: calcium oxalate, calcium phosphate
uric acid = not visible on x-ray
struvite = produced by bacteria hence associated with infection
cystine = cystinuria (autosomal recessive disease)
staghorn calculus =
- stone forms in shape of renal pelvis (horns extend into renal calyces)
- may be seen on plain x-ray films
- normally made of struvite
- in recurrent UTIs, bacteria can hydrolyse urea to ammonia = solid struvite
presentation of kidney stones?
may be asymptomatic
renal colic - unilateral loin to groin pain, colicky as stone moves and settles (fluctuating in severity)
restlessness
may also be: Haematuria Nausea or vomiting Reduced urine output Symptoms of sepsis, if infection is present
investigate kidney stones?
- urine dipstick (usually shows haematuria), can also be used to exclude infection
- blood test can show signs of infection and show kidney function eg. hypercalcaemia
- abdominal x-ray can show calcium-based stones (but not uric acid as is radiolucent)
- non-contrast computer tomography (NCCT) of kidneys, ureters, bladder (CT KUB) is initial investigation within 24 hours of presentation
- ultrasound of KUB is less preferred alternative to CT as neg result does not exclude stones, less effective at identifying but used if pregnant or child
- analyse stones to help determine risk and avoid recurrence
hypercalcaemia is a cause of kidney stones. presentation of hypercalcaemia? (mnemonic) + 3 main causes
renal stones, painful bones, abdominal groans and psychiatric moans
calcium supplementation, hyperparathyroidism and cancer (eg. myeloma, breast or lung cancer)
management of kidney stones?
- NSAIDs most effective analgesia eg. intramuscular diclofenac (IV paracetamol if NSAID not suitable)
- antiemetics for nausea/vomiting eg. metoclopramide
- antibiotics if infection
watchful waiting in stones less than 5mm - tamsulosin (alpha-blocker) to help aid spontaneous passage of stones
- surgery
surgical interventions for kidney stones?
Extracorporeal shock wave lithotripsy (ESWL):
external machine, shock waves directed at stone to break into smaller parts
Ureteroscopy and laser lithotripsy:
camera via urethra, bladder, ureter
stone identified and broken by lasers
Percutaneous nephrolithotomy (PCNL):
under general anaesthetic
nephroscope (camera) inserted via small incision on patients back
nephrostomy tube may be left in place to drain kidney
open surgery:
rare, invasive
how are recurrent kidney stones treated?
- increase oral fluid intake (2.5 - 3l per day)
- add lemon juice to water as citric acid binds to urinary calcium
- avoid carbonated drinks due to phosphoric acid which promotes calc oxalate formation
- reduce dietary salt intake ( <6g per day)
- normal calc intake
reduce the intake of oxalate-rich foods (for calc)
educe the intake of purine-rich foods (for uric)
limit dietary protein
meds - potassium citrate, thiazide diuretics eg. indapamide
wtf is prostate cancer? + RF
- most common cancer in men
- majority are adenocarcinomas and grow in peripheral zone of prostate
- many are very slow growing
advanced cancer spreads to lymph nodes and bones - almost always androgen-dependent meaning they rely on androgen hormones eg. testosterone
RF: increasing age family history black afro/Caribbean origin tall anabolic steroids
presentation of prostate cancer?
may be asymptomatic
lower urinary tract symptoms - hesitancy, frequency, weak flow, terminal dribbling, nocturia
haematuria
erectile dysfunction
symptoms of advanced decease/red flags - weight loss, bone pain, cauda equina syndrome (nerves in lower back become compressed causing numbness in legs)
what is PSA and PSA testing?
epithelial cells of the prostate produce prostate-specific antigen (glycoprotein secreted in semen, small amount enters blood)
enzymatic activity helps thin the thick semen into a liquid consistency after ejaculation
not produced anywhere else in body
raised level can indicate prostate cancer
testing is unreliable but can lead to early detection
common causes of raises: cancer, benign prostatic hyperplasia, prostatitis, UTI, exercise, recent stimulation
investigate for prostate cancer?
prostate exam DRE:
benign prostate = smooth, symmetrical, soft, central sulcus
prostatic hyperplasia = generalised enlargement
infected/inflamed prostate/prostatitis = enlarged, tender, warm
cancerous prostate = firm, hard, asymmetrical, craggy, irregular, loss of central sulcus, hard nodule
cancer suspicion leads to 2 week wait urgent referral
multiparametric MRI: first line likert scale - 1 very low 2 low 3 equivocal 4 probable 5 definite
prostate biopsy:
based on exam, psa level, likert 3+
false-negative if cancerous area is missed
multiple needles used to target diff areas
-Transrectal ultrasound-guided biopsy (TRUS) = probe inserted into rectum
- Transperineal biopsy = needles into perineum under LA
isotope bone scan:
radioactive isotope is given by intravenous , bones absorb, gamma camera is used to take pictures of skeleton, metastatic bone lesions take up more of the isotope
gleason grading: histology of biopsies 1-10, higher score = cells have mutated further from normal prostate tissue = worse prognosis 6 = low 7 = intermediate 8+ = high
TNM staging:
T (tumour), N (lymph nodes) and M (metastasis)
manage prostate cancer?
Surveillance or watchful waiting in early prostate cancer
External beam radiotherapy directed at the prostate (can cause proctitis - inflam in rectum, Prednisolone suppositories can help reduce this)
Brachytherapy (radiation source inserted near tumour, can cause inflam of nearby organs)
Hormone therapy (reduce level of androgens, used in combo w/ radiotherapy or alone if no cure possible) eg. androgen-receptor blockers, GnRH agonists, bilateral orchidectomy (remove testicles) - side effects: Hot flushes, Sexual dysfunction, Gynaecomastia, Fatigue, Osteoporosis
Surgery eg. radical prostatectomy
