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
Testicular torsion ix
• Power/colour Doppler/Duplex US of the tests
• Arterial inflow
o Decreased in testicular torsion
o Increased in epididymo-orchitis
• Grey-scale US
o Whirlpool sign (the swirling appearance of the spermatic cord from torsion as the US probe scans perpendicular to the spermatic cord)
o Presence of fluid
(CRP is not raised in testicular torsion
(scintigraphy decreased uptake of radioactive technetium – 99m to the affected testicle)
If a patient present with testicular torsion acutely, first line ix is exploratory surgery as you only have 6h to save the testis
First line ix for any scrotal mass
USS testis
Bladder cancer ix
• Cystoscopy + biopsy
o Low grade tumours – papillary + readily visible
o High grade tumours – flat + more difficult to see
- Urinary cytology
- Urinalysis – haematuria
- MRI/CT – for staging
Hydrocele ix
Ultrasound - exclude tumour
Testicular tumour markers – AFP, βHCG, GGT, LDH
Urine dipstick/MSU – check for infection
Epididymo-orchitis ix
• Exclude STI
o Gram-stained urethral smear
o Urethral swab for Gonorrhoeae, Chlamydia trachomatis
• Exclude UTI
o Urine dipstick
o MSU microscopy + culture
- Exclude testicular torsion – Duplex USS
- Bloods – if septic
- Ix of the urinary tract to detect anatomical abnormalities that can predispose someone to UTI
- TB – 3x early morning urine samples (acid-alcohol fast bacilli)
- Mumps – mumps IgM/IgG serology
Hernia ix
Clinical
o US – 1st line
Post-strep Glomerulonephritis ab
Anti-DNase
Anti-hyaluronidase
Anti-Streptolysin O
Diabetic nephrotpathy on histology
Mesangial expansion
BM thickening
Glomerulosclerosis
UTI ix
• Dipstick
o Nitrites, Leukocytes
• Urine MC+S
o Gram negative bacilli!! - E. coli!
US diagnostic criteria for PKD polycystic kidney disease
For individuals with positive FHx
• >2 unilateral/bilateral renal cysts at age >30 years
• >2 bilateral cysts bn 30-59
• >4 bilateral cysts at age >60
• Dx is supported by hepatic/pancreatic cysts
For individuals w/out FHx
• >10 cysts in each kidney
• No manifestations suggesting an alternative renal disease
Renal cell carcinoma RCC ix
- There is often no abnormality on examination
- Exclude UTI – urinalysis, cytology, culture, sensitivity
- Cystoscopy to exclude bladder cancer as a cause of haematuria
- Renal function tests will be normal if one kidney is functioning well
- Increased blood pressure - renin release
• FBC o Iron deficiency anaemia (haematuria) o Polycythaemia (some RCC produce EPO + Increased Hct) o Increased ESR o Increased Ca
• US abdo/pelvis
o Appropriately sensitive initial imaging for determining if cystic renal lesions are benign, especially in hereditary syndromes prone to cystic disease
• CT abdo/pelvis
o Definitive test for dx + staging of RCC
• Renal biopsy
• Metastases (commonly metastasises to lungs + bones)
o CXR – Canon ball secondaries in lung
o LFTs - raised transaminases (AST, ALT) + poor liver function (PT>14s, APPT >34s)
o Skeletal survey/bone scan
o Brain CT
o raised ALP
renal artery stenosis RAS ix
Bloods
• U+Es, eGFR
o Hypokalaemia may suggest RAS due to activation of the renin-angiotensin system
- Blood glucose
- Lipid profile – renovascular disease is likely to be part of a more extensive atherosclerotic disease
• Aldosterone : Renin
o <20 - excludes primary aldosteronism as a case of HTN + hypokalaemia
o High aldosterone + high renin
Urine
• 24h urinary protein excretion
In the absence of diabetic nephropathy or HTN glomerulosclerosis, RAS is not associated with proteinuria
• Urinalysis to exclude RBC/red blood cell casts (glomerulonephritis)
Imaging
• Conventional angiography/Renal arteriogram (digital subtraction renal angiography)
o Gold standard
o Most sensitive + specific test in the evaluation of RAS
o Invasive
o >50% reduction in vessel diameter
o Endovascular therapy can be carried out at the same time
• MRI angiography - Amir Sam mentions this in his lecture (DPD6) as the gold standard
o Can be used to assess blood flow rate, renal perfusion rate, GFR
o Visualises the renal arteries and peri-renal aorta
o Has only been validated for disease in the proximal renal arteries
o Safer than conventional angiography as it does not use nephrotoxic contrast medium
• Renal US
o Performed in those with renal impairment
o Not diagnostic for renovascular disease
o Dx suggested if there is a significant difference (>1.5cm) in kidney size - asymmetrical kidneys
• Dupplex renal US
o Measures flow velocity in renal artery stenosis as a means of assessing the severity of the stenosis
Varicocele ix
• Examination with the patient standing
o Scrotum w varicocele hangs lower than on N side
o Valsalva manoeuvre whilst standing increases dilation
o There may be a cough impulse
o Palpation of the spermatic cord above the testicles – “back of worms” appearance
• US – venous dilation >2cm
• Colour Doppler studies
o Used as adjunct to physical examination - not indicated unless physical examination is inconclusive
o Colour demonstrates direction of blood flow (incl. reverse flow in the varicocele)
o If the varicocele comes on quickly it can be caused by a renal tumour which raided into the testicular vein + caused the veins around the testicle to obstruct + dilate
Dx of urethral strictures
Urethrography
Dye is inserted through the distal end of the meatus
Dx of strictures, determines their length and number
Gold standard ix for all urinary incontinence
Urodynamic studies
A 61 y/o man complains of hesitancy, poor stream, terminal dribbling
Distended badder suprapubically
Which ix
radionuclide studies urodynamic study abdominal US Bladder scan cystoscopy
Urodynamic study
Overflow incontinence
- involuntary release of urine from an overfull bladder
- occurs in people with blockage of the bladder outlet (e.g. BPH, Prostate cancer)
Gold standard ix for all urinary incontinence –> Urodynamic studies
Goodpasture’s syndrome
antibodies
renal biopsy
immunofluorescence
Ab trigger a T2 hypersensitivity reaction – renal failure, pulmonary haemorrhage, haemoptysis
Anti-GBM antibodies
Renal biopsy = focal/diffuse crescentic glomerulonephritis
Immunofluorescence = IgG ab, C3 complement deposition on GBM
Antegrade vs retrograde pyelography
Antegrade - to ix potential area of obstruction within the kidney
Retrograde - to ix obstruction via a catheter
Analgesic nephrotpathy vs acute tubulointerstitial nephritis
Analgesic nephrotpathy chronic NSAID use haematuria Anaemia UTI
Acute tubulointerstitial nephritis drug hypersensitivity reaction fever rash arthralgia oesinophilia
Diabetic nephropathy
Progressive damage to the filtering capacity of the kidneys
US reveals large kidneys
Kimmestiel- Wilson nodules seen on histology - hallmark of diabetic glomerulosclerosis
Initial increase in GFR
glomerulosclerosis allows passage of protein into urine but not blood - nephrothic syndrome
SGLT2 inhibitors have been shown to slow progression to ESRF e.g. empagliflozin
Pyelonephritis on CT
Gas accumulation due to parenchymal infection
gram -ve infection commonly
