Urology - ix Flashcards
Ix for AKI
Bedside - Urine dip Blood - UTI, stones, malignancy Protein - intrinsic renal disease Nitrates + Leukocytes - UTI, pyelonephritis 2o to stones Glucose Specific gravity
- Bladder scan
Obstructive picture - ECG
Can show ppt cause (e.g. MI)
Can show complications - pericarditis, hyperkalaemia (flattened P waves, wide QRS, tall T waves)
Bloods
- U+E, Cr, K
Will confirm renal impairment
High serum urea + creatinine
Ca goes down + Phosphate goes up very quickly in renal failure
Baseline for monitoring the patient’s progress
- FBC, LFT, CRP, ABG, Blood cultures if infection is suspected
Imaging
- USS KUB
Used if pt is truly anuric, signs of sepsis present
Urinary tract obstruction, kidney size, kidney structure Inflammation of the kidneys
Hydronephrosis
- CT KUB
If you suspect renal stones - CXR if fluid overloaded
Other tests
- Renal biopsy - glomerulonephritis
- MSU
MC+S
Red cell casts - glomerulonephritis
Bence Jones protein - myeloma screen
- Urine biochemistry - may help distinguish prerenal failure from established acute tubular necrosis
- Features of systemic disease
ANCA (systemic autoimmune vasculitis), Anti-GBM, SLE immunology (ANA, dsDNA, complements)
- Creatine kinase
?Rhabbomyolisis
Difference between prerenal failure + acute tubular necrosis + SIADH
Prerenal failure
- Kidneys retain salt + water
- Urinary sodium <20 mmol/L
- Urine is concentrated (osmolarity >500mmol/L)
- Urine:plasma osmolarity ratio >1.5:1
Established acute tubular necrosis
- Can’t concentrate urine or conserve sodium
- Urinary sodium >40 mmol/L
- Urine is dilute (osmolarity <350mmol/L)
- Urine:plasma osmolarity ratio <1:1
SIADH
- Excess water reabsorbed from kidneys
- Low serum Na, low plasma osmolarity
- High urine Na (since most of the water has been reabsorbed), high urine osmolarity
- Urine is concentrated
- Plasma is dilute
- Urine osmolarity > plasma osmolarity
- Urine : plasma osmolarity >1:1
Ix for CKD
- Urine dipstick + microscopy (protein, glucose, ACR)
To exclude infection
Albuminuria - glomerular/tubointestritial disease, UTI
Macroscopic haematuria - renal cell carcinoma, renal calculi, UTI
Red blood cell casts - glomerulonephritis
White cell casts - Interstitial nephritis, UTI
(if there is proteinuria, send ACR - if ACR 30-300mg/g for >3 months - CKD - Serum + protein electrophoresis, urine BJP Protein electrophoresis
- monoclonal band
Bence Jones protein (monoclonal protein) possibly representing multiple myeloma - GFR
Gold standard measurement
Assessment of renal function - USS KUB
To exclude obstruction
To assess kidney size - Biochemistry (hypocalcaemia, hyperkalaemia, hyperphosphataemia, high ALP in renal osteodystrophy, high PTH if seconday hyperparathyroidism)
- Haematology (normocytic anaemia)
- Serology
- Urine
- ECG + echo
- CXR - pericardial effucion or pulmonary oeddema
- Imaging of the renal tract
- Renal biopsy - considered once prerenal + postrenal disease have been excluded (esp if structure + size are normal on US –> suggests a more acute cause)
- Glucose (diabetic glomerulosclerosis)
Biochemistry in CKD (rheumatology)
- c-ANCA - granulomatosis with polyangiitis (Wegener’s)
- p-ANCA - microscopic polyangiitis
- Anti-GBM - goodpastures
- ds DNA, ANA - SLE
Imaging of the renal tract CKD
- AXR - radio-opaque stones, nephrocalcinsis
- US
Small kidneys in advanced CKD
Large kidneys in diabetic nephropathy
Structural abnormalities e.g. polycystic kidneys, hydronephrosis, to exclude obstruction - CT KUB
To define renal masses, cysts, most sensitive test for identifying renal stones - MRI - contraindications to CT
- Renal angiography - renal artery stenosis
- Dupplex scan kidneys
Indications for renal biopsy
- Acute renal impairement
- Haematuria
- Proteinuria (suggests glomerular disease)
Urine results in glomerular disease, tubular disease, pre-renal renal failure
Glomerular disease - red cells, red cell casts, proteinuria (often heavy)
Oliguria not a common presentation of AKI
Proteinuria is always glomerular disease
Prerenal failure
• Kidney retains salt + water
• Urinary sodium <20mmol/L => urine is concentrated (osmolarity >500mmol/L)
• Urine:plasma osmolarity ratio >1.5:1
Established acute tubular necrosis
• Can’t concentrate their urine or conserve sodium
• Urinary sodium >40mmol/L => urine is dilute (osmolarity <350mmol/L)
• Urine:plasma osmolarity ratio <1:1
Painless haematuria investigations
> 40
- suspect tumours
- Cystoscopy
- Urine cytology
- CT/US/IVU
Young pt - more likely to have a renal cause (thin glomerular membrane, igA nephropathy (glomerular dissaes, igA deposits in mesangium), Alport’s syndrome (deafness, heamaturia, inherited, sex linked)
- Renal function tests
- Blood tests for underlying systemic immune disease
- Biopsy to confirm dx
CT urogram or KUB – gold standard
Ix
Kidneys + ureters show clearly on CT
Flexible cystoscopy
Bladder doesn’t look clearly on CT, go for cystoscopy – might miss a bladder tumour w CT
Features of CKD
Pt only gets symptoms when eGFR falls to very low levels (i.e. <30 ml/min/CKD 4/5)
- Fatigue
- Malaise
- Thirst
- Anorexia
- Nausea
- Itching
- Uraemic skin (lemon yellow, bruises)
- HTN
- Small scarred kidneys
- Anaemia
- Metabolic acidosis (not hypoxic)
- Hypocalcaemia
- Hyperphosphataemia 2o hyperparathyroidism
- Low to normal [Ca], high PTH, low plasma [Ca] due to e.g. renal failure, vitamin D deficiency stimulates release of PTH to try to normalise serum calcium
Rhabdomyolysis biochemistry
- Raised CK (x5 normal)
- Raised U+Cr
- Raised K, Mg, PO43-
- Low Ca
Polycystic kidney disease PKD
- US (first line)
- CT AP (second line)
Bloods • FBC o Hb – polycystic kidneys can produce EPO which increases Hb • U+E, Cr o Creatinine often normal
Imaging • Renal US o Cysts in kidneys o Renal enlargement • CT/MRI AP - 2nd line
• Urinalysis
o To detect proteinuria -higher likelihood of progression to CKD, higher incidence of LVH
o Microscopic + macroscopic haematuria common
o Check for UTI
• CT brain
o If sudden-onset severe or unusual headache
(pt w PKD at risk of intracranial aneurysm or SAH)
Ix for
a) SLE
b) Multiple Myeloma
c) Pre-renal renal failure
d) Rhabdomyolysis
e) Bladder tumour
a) anti-nuclear ab
b) Protein electrophoresis - monoclonal band
c) Volume status + BP (hypovolaemia, dehydration)
d) Serum CK
e) Cystoscopy
Urolithiasis ix
kidney stones
- Bedside - Pregnancy test
to exclude ectopic pregnancy + bc pt will undergo a CT scan - Urine dipstick
Microscopic haematuria - CT KUB - 90% of renal stones are radio-opaque
First line for kidney/ureteric stones, gold standard
Pyelonehritis, hydronephrosis, +/or hydroureter due to obstruction - signs of inflammation around the kidneys - perinephric fat stranding
Will also detect AAA - Serum calcium, phosphate, urate, uric acid level
High uric acid/calcium - kidney stones
Should be requested on anyone with a proven stone to look at its components and decide on treatment
Bloods
- U+Es, Cr
Check renal function - AKI, hydronephrosis, hyperkalaemia
Cr/U might be up because of dehydration
If both U+Cr are up - renal injury (e.g. acute tubular necrosis)
Usually no fever with kidney stones
-MRU if pregnant
- US KUB if pregnant
Doesn’t show stones in ureter
Will show hydronephrosis, stones in the kidney
Will not tell you if an AAA is bleedingAny pt w flank/back/abdo pain + AAA on US –> contrast CT to look for a leak of their AAA
Hyperkalaemia findings on ECG
- Prolonged PR
- Widened QRS
- Tall tented T waves
- Absent P waves
Severe hyperkalaemia - sinusoidal waves
> 5.5 mM Tall tented T waves
6.5 mM Flattening of p waves
7.5 mM Prolonged PR + QRS intervals, bradycardia
Renal US scan offered to all people with CKD who… (6)
- Have an accelerated progression of CKD
- Have visible/persistent invisible haematuria
- Have symptoms of urinary tract obstruction
- Have a FHx of PKD and are >20 y/o
- Have a GFR <30 ml/min/1.73m2
- Are considered by a nephrologist to require renal biopsy
Ix for glomerulonephritis/nephrotic syndrome
- Urinalysis
- MSU
To exclude UTI - ACR
Always ordered as a follow up to urinalysis showing proteinuria - Bloods
Anaemia - renal failure
Hyperlipidaemia in nephrotic syndrome
LFTs - if Hep B/C suspected
ESR/CRP - if systemic inflammation e.g. vasculitis suspected
Fasting glucose
Autoimmune screen if underlying autoimmune disease is suspected
Serum albumin low in nephrotic syndrome (<30g/L)
Increased K+, Increased PO43-, Low HCO3- in renal failure - eGFR
- Imaging
USS KUB - size of kidneys, to exclude obstructive uropathy - Ig, serum, urine electrophoresis
Increased gamma globulin –> SLE, amyloidosis, lymphoma
Increased monoclonal paraprotein –> myeloma, AL (light chain) amyloidosis - Renal biopsy
If intrinsic kidney disease is suspected
Urgently performed if GN is suspectedNephrotic syndrome is most commonly caused by glomerulonephritides Adults should all get a renal biopsy In Children the most common cause of nephrotic syndrome is minimal change disease/glomerulonephritis - normally reverses with steroids [biopsy can be avoided unless there are other concerning features or little response to steroids]
How ix the following
a) Pt w known IHD taking ACEi + develops renal failure
b) 24yo long distance runner w R sided groin pain + vomiting
c) 65yo M poor stream, terminal dribbling, hesitancy
d) 75yo F confusion, dysuria, fever
e) 35 yo urinary incontinence following coughing or sneezing
a) RAS - MR angiography
b) Kidney stones - CT KUB
c) Urinary tract obstruction - US KUB
d) UTI - urine dipstick, MC+S
e) Stress incontinence - urodynamic studies
Urine results in tubular disease
Tubular disease - minimal blood, small urine, granular/white cell casts
Urine results in pre-renal renal failure
Pre-renal renal failure - nothing abnormal in urine
BPH ix
• Urine dip = exclude infection
• DRE
Enlaeged, smooth, firm, elastic, free from prostate, obliterated median sulcus/palpable midline groove
• Bloods
o U+Es – impaired renal function
o PSA - suggests underlying prostate cancer or prostatitis (N PSA: <4 ng/ml)
o LFTs
Increased ALP – of prostate cancer has metastasised to the bone
Increased ALP – in an elderly person w undiagnosed Paget’s disease of bone
• Flow rate + postvoid residual bladder scan in clinic
o If flow is <12 ml/s - obstructed flow
o Do not routinely offer this to men with LUTS at initial assessment
Ix to consider
• Imaging
o US urinary tract - ?hydronephrosis
o Bladder scan – measure pre- and post-voiding volumes
o TRUS (transrectal US) – assessment of bladder size + volume
Prostate cancer ix
- DRE
Irregular, stony hard, nodule within one lobe, enlarged, asymmetry of the gland, induration of part or all the prostate, lack of mobility
• Multiparametric MRI – recommended by NICE as a FIRST LINE IX for pt suspected clinically of having localised prostatic cancer
o Positive MRI scan – move onto biopsy
o Negative MRI scan – reassure + continue monitoring PSA levels, ask them to come back if PSA starts rising significantly
• PSA Test
• Prostate biopsy
o TRUS biopsy (transrectal biopsy of the prostate guided by US) - risk of sepsis, bleeding
o Now carried out
Transperineally biopsy
Classic picture: hypoechoic area in the peripheral zone of the prostate
• LFTs/bone profile - check for metastatic disease
Ix to consider
• PCA3 urine test
o Superior to PSA total
o Indication: to determine whether a man needs a repeat biopsy after an initially negative biopsy outcome
Staging - TNM - MRI/Bone scan
PSA Values
PSA <4 ng/ml Very low risk of prostate cancer
PSA 4-10 ng/ml Moderate risk of prostate cancer
PSA >10 ng/ml High risk of prostate cancer
PSA >40 ng/ml High risk of metastatic prostate cancer
PSA >100 ng/ml Almost certainly metastatic prostate cancer
Normal PSA <4ng/ml
TURP complications
Retrograde ejaculation – you ejaculate up into the bladder bc internal urinary sphincter is relaxd
Erectile dysfunction
Haemorrhage
Urinary infection
Urethral stricture
Incontinence
TURP syndrome – seizures or cardiovascular collapse caused by hypervolaemia + hyponatramia due to absorption of glycine irrigation fluid
Testicular cancer ix
• USS of both tests – FIRST LINE TEST, urgent on the same day
o If US does not confirm a mass + suspicion is high (e.g. abnormal tumour markers) proceed to CT AP
• Tumour markers (if USS highly suggestive of a tumour)
o Aid Dx
o Monitor response to treatment
o Monitor for relapse
o α-fetoprotein (AFP) – 50-70% of teratomas, not seminomas
o β-human chorionic gonadotrophin (β-HCG) – 40-60% of teratomas, 30% of seminomas
o gamma glutamyl transpeptidase (GGT) – 33% of seminomas
o LDH – less specific, elevated in many cancers as it’s released during tissue breakdown, most commonly raised in seminomas but in testicular cancer used mainly to asses tumour burden
• Staging scans
o Plain CXR on the same day
o CT CAP (chest abdo pelvis) – used to assess extratesticular metastasis, might show enlarged retroperitoneal lymph nodes
A biopsy is generally not advised in the evaluation of a testicular mass due to risk of seeding; diagnosis is established by removing and examining the involved testicle.
o Cystic spaces – teratoma
o No cystic spaces – seminoma
