Urinary Tract Flashcards
Kidneys: anatomical position
Retroperitoneal
Typically T12 - L3
Adrenal glands immediately superior
Kidneys: Layers
Superficial to deep Pararenal fat Renal fascia (Gerota's fascia) Perirenal fat Renal capsule Kidney
Kidney: parenchyma areas
Cortex (outer)
Medulla (inner)
Kidney: Organisation of parenchyma
Cortex extends into medulla, dividing it into triangular shapes: renal pyramids
Apex of perms is called renal papilla
Minor calyx collects urine from pyramids and merge to form major calyx.
Major calices drain into renal pelvis then into the ureter.
Kidney: arterial supply
Renal arteries (paired branches of aorta at L1, immediately distal to origin of SMA)
Right renal artery passes IVC posteriorly
Renal artery divides into anterior (75%) and posterior (25%) division. Supply 5 segmental arteries.
Segmental –>
interlobar arteries –>
Arcuate arteries –>
Interlobular arteries –>
Afferent arterioles –>
Glomerulus –>
Efferent arterioles
Peritubular network (supplies nephron)
Kidney: venous drainage
Left and right renal veins
Leave hilum anterior to renal artery
Drain into IVC
Left renal vein is anterior to abdominal aorta
Kidney: lymphatic drainage
Lateral aortic (para-aortic) lymph nodes
Ureters: anatomical course
Arise from renal pelvis at ureteropelvic junction
Descend through abdomen along anterior surface of posts major.
Retroperitoneal.
At SI joints, ureters cross pelvic brim entering pelvic cavity.
Cross bifurcation of common iliac.
Travel down pelvic wall at level of ischial spines. Turn anteromedially.
Pierce lateral aspect of bladder in oblique plane.
Ureters: blood supply
Abdominal: renal artery, testicular/ovarian artery, ureteral branches (direct of abdominal aorta)
Pelvic: superior and inferior vesical arteries
Ureters: venous drainage
Renal vein, testicular/ovarian vein, ureteral vein, superior and inferior vesical veins
Ureters: nerve supply
Renal, testicular/ovarian and hypogastric plexuses
Ureters: narrowest points
Uretopelvic junction
Pelvic brim
Entrance of ureter to bladder
Bladder: functions
Temporary storage of urine
Assists in expulsion of urine
Bladder: shape
Apex: superior
Body: between apex and fundus
Fundus (or base): posterior
Neck: convergence of fundus, continuous with urethra
Bladder: Blood supply
Superior vesical artery, branch if internal iliac
In males, supplemented by inferior vesical artery.
In females, vaginal artery.
Obturator and inferior gluteal may also contribute branches
Bladder: venous drainage
Vesical venous plexus. Empties into internal iliac vein.
In males, vesical plexus is in continuity at the retropubic space with prostate venous plexus (plexus of Santorini)
Bladder: lymphatic drainage
Superolateral: external iliac lymph nodes
Neck, fundus: internal iliac, sacral, common iliac nodes
Bladder: innervation
Sympathetic: hypogastric nerve (T12-L2). Causes relaxation of detrusor muscle, promoting urine retention
Parasympathetic: pelvic nerve (S2-S4). Causes contraction of detrusor muscle, stimulating micturation
Somatic: pudenal nerve (S2-4). External urethral sphincter giving voluntary control of micturation
Bladder: wall and musculature
internal to external: Transitional epithelium Laminar propria Submucosa Detrusor muscle
Phases of micturition
Storage phase
Voiding phase
Storage phase of micturition
Controlled by continence centres in pons which control continuance centres in spinal cord. Storage requires: relaxation of detrusor muscle, contraction of internal & external urethral sphincters Sympathetic nuclei (T12-L2) --> hypogastric nerve --> detrusor & IUS
Voiding phase of micturition
Parasympathetic control
Afferent signals from bladder ascend to pontine micturition centre and cerebrum.
Upon voluntary decision to micturate, neurones of pontine micturition centre fire, exciting sacral preganglionic neurones.
Subsequent parasympathetic stimulation to pelvic nerve (S2-4) to muscarinic receptors on detrusor muscle, causing contraction.
Pontine micturition centre also inhibits Onuf’s nucleus reducing sympathetic simulation to IUS, causing relaxation.
Conscious reduction in voluntary contraction of EUS
Causes of urinary retention
BPH Nerve dysfunction Infection Constipation Drugs (anticholinergics, antidepressants, opioids)
Urethra: parts
Prostatic urethra
Membranous urethra
Penile (bulbous) urethra
Prostatic urethra
Begins as continuation of bladder and neck
Passes through prostate gland
Receives ejaculatory ducts and prostatic ducts
Widest part of urethra
Membranous urethra
Passes through pelvic floor and deep perineal pouch
Surrounded by external urethral sphincter
Narrowest and least dilatable portion of urethra
Penile urethra
Passes through bulb and corpus spongiosum of penis
Ends at external urethral orifice (the meatus)
Receives bulbourethral glands proximally
Urethra: blood supply
Prostatic: inferior vesical artery (branch of internal iliac)
Membranous: bulbourethral artery (branch of internal pudendal artery)
Penile: branches of internal pudendal artery
Female: internal pudendal artery
Urethra: innervation
Prostatic plexus (mix of sympathetic, parasympathetic, visceral afferent)
Female: Pudenal nerve
Urethra: Lymphatic drainage
Prostatic/mebranous: obturator and internal iliac nodes
Penile: deep and superficial inguinal nodes
Female: internal iliac nodes, superficial inguinal lymph nodes
Zones of the prostate
McNeal’s zones
Central zone
Transitional zone
Peripheral zone
Central zone of the prostate
Surrounds ejaculatory ducts
25% of normal prostate
Glands drain obliquely into urethra (relatively immune to urine reflux)
Transitional zone of the prostate
Located centrally, surrounds the urethra
5-10% of normal prostate volume
Typically undergo BPH
Peripheral zone of prostate
Main body of gland: 65%
Ducts vertically drain into urethra, allowing urine reflux
Fibromuscular storm of prostate
Situated anterior to gland
Merges with tissue of urogenital diaphragm
Blood supply to prostate
Prostatic arteries, branches of internal iliac
Venous drainage of prostate gland
Prostatic venous plexus, draining into internal iliac veins
Innervation to the prostate
Inferior hypogastric plexus
Anatomical relations of the prostate
Neurovascular bundle to penis (can be damaged in prostatectomy)
Kidney stones: composition
Calcium oxalate (35%) Calcium phosphate (10%) Mixed oxalate/phosphate (35%) Struvite (magnesium ammonium phosphate) Urate (only radiolucent stones) Cystine stones
Struvite stones
Large soft stones
Commonest cause of “stag horn calculi”
Associated with UTI
Pathophysiology of stone formation
Over-saturation of urine
Urate stones: high levels of purines (from red meat diet or myeloproliferative disorders)
Cystine stones: associated with homocystinuria
Criteria for Inpatient management of stones
Post-obstructive AKI
Uncontrollable pain
Evidence of infected stones
Large stones >5mm
Management of renal calculi
Evidence of obstruction/infection: stent/nephrostomy Small stones (<2mm): Extracorporeal shock wave lithotripsy (ESWL), CIs: pregnancy/near bony landmark Large stones: Percutanous nephrolithotomy
Bladder stones
Urine stasis. Commonly seen in chronic urine retainers.
Increases risk for SCC bladder.
Renal cancer: types
Renal cell carcinoma (85%)
Transitional cell carcinoma
Nephroblastoma (Wilm’s tumour, paeds)
SCC (secondary to chronic inflammation, e.g. stones/UTI)
Renal cell carcinoma, pathology, spread and RFs
Adenocarcinoma of renal cortex, predominantly from proximal tubule.
Most commonly in upper pole of kidney
Spread: local invasion (adrenal, renal vein, IVC), lymphatic (pre-aortic/hilar), haematogenous (bones, liver, brain, lung)
RFs: smoking. Industrial (cadmium, lead, aromatic hydrocarbons), dialysis, HTN, obesity, polycystic kidney, horseshoe kidney
Renal cell carcinoma, clinical
Haematuria. Non-specific Sx. Flank mass. Left varicocele (compression of left testicular vein)
Paraneoplastic: polycythemia (EPO), hypercalcaemia (PTH), HTN (renin)
Sx of metastasis, 25% have mets at diagnosis
Ix: US for haematuria, CT with IV contrast.
Renal cell carcinoma
Localised disease: Partial/radical nephrectomy
Metastatic disease: immunotherapy, biological agents (Sunitinib, Pazopanib: tyrosine kinase inhibitors)
Bladder cancer: types
Transitional cell carcinoma (80-90%)
Squamous cell carcinoma
Adenocarcinoma
Sarcoma
Bladder cancer: classifications
Non-muscle invasive bladder cancer
Muscle-invasive bladder cancer
Locally advanced
Metastatic
Layers of the bladder wall
Inner to outer: Transitional epithelium (urothelium) Lamina propria Muscularis propria Fatty connective tissue
Bladder cancer: risk factors
Smoking Age Aromatic hydrocarbons (industrial dyes/rubbers) Schistosomiasis (SCC) Radiation to pelvis
Bladder cancer: investigations
Haematuria: BP Bloods: U&Es, glucose, FBC, PSA, >50: 2WW, CT urogram +/- contrast <50 USS
Cystoscopy
Rigid cystoscopy & biopsy
CT staging (muscle invasive)
Bladder cancer: management
NMI: resection via TURBT +/- adjuvant intravesical therapy (Bacille Calmette-Guerin). If high risk disease: radical cystectomy
MI: Radical cystectomy + urinary diversion (ill conduit/bladder recon), neoadjuvant chemo.
Locally advanced/metastatic: chemo
Benign prostatic hyperplasia (BPH): risk factors
Age
FH
Black African/Caribbean ethnicity
Obesity
BPH: clinical features
LUTS: voiding symptoms (hesitancy, weak stream, terminal dribbling, or incomplete emptying)
DRE: firm, smooth, symmetrical prostate
BPH: medical management
a-adrenoreceptor antagonist (a-blocker): alfuzosin, doxazosin, tamsulosin or terazosin.
SEs: postural hypotension, retrograde ejaculation, floppy iris syndrome
5α-reductase inhibitors: Finasteride
SEs: can take 6months to have effect
Anti-cholinergic: Oxybutynin
BPH: surgical management
If refractory to medical management or develop complications of BPH (high pressure retention)
(Minimally invasive)
TURP (complications: TURP syndrome, haemorrhage, sexual dysfunction, retrograde ejaculation, urethral stricture)
TURP Syndrome
Hypoosmolar irrigation during procedure
Leads to fluid overload and dilution effect
Hyponatraemia
Sx: confusion, nausea, agitation, visual changes
Rx: Manage as hyponatraemia, replacing Na
Prostate cancer: epidemiology
Most common cancer in men.
26% of male cancer diagnosis.
1 in 8 men will get prostate cancer in their lifetime.
Prostate cancer: aetiology
Exact aetiology unknown.
Growth of cancer is influenced by androgens.
>95%: adenocarcinomas
75% from the peripheral zone. 20% transitional zone. 5% central zone. Often multifocal.
Acinar adenocarcinoma (most common) from glandular cells that line prostate.
Ductal adenocarcinoma from cells that line ducts: Grow and metastasise more rapidly
Prostate cancer: clinical
LUTS. Haematuria, dysuria, incontinence, haematospermia. Suprapubic/loin pain.
Mets: bone pain, lethargy, anorexia.
DRE: asymmetrical nodularity, firm
Prostate cancer: Investigations
PSA
MRI prostate
Targeted biopsy: transperineal, transrectal US guided
Gleason Grading System: most common growth pattern + second most common
Prostate cancer: management
Low risk disease: active surveillance, radical treatments offered to those who show evidence of disease progression
Intermediate/high risk: radical prostatectomy
Metastatic: chemotherapy, anti-hormonal agents
Radical prostatectomy: open approach, laparoscopic, robot. SE: ED, incontinence, bladder neck stenosis
