B10 Week 2 Flashcards
How does urine form and travel?
Urine forms in the kidneys and collects in the renal pelvis. It travels down the ureters to be stored in the bladder and excreted via the urethra
How does urine travel in the ureter?
Entry of urine into renal pelvis causes it to dilate. Induces pacemakers to produce action potential in ureter for peristaltic contractions to propel urine.
What are the divisions of the ureter?
Renal pelvis
Abdominal
Pelvic
Intramural
What are the natural ureteric constrictions?
Pelvi-ureteric junction
Bifurcation of common iliac artery
Vesico-ureteric junction
What is the pelvic-ureteric junction?
Area where the renal pelvis joins to the ureter.
What is the vesico-ureteric junction?
Area where ureter enters the bladder. Obstruction can occur here if the ureter is too short via Paquin’s law.
What is the blood supply to the ureter?
Segmental based on the ureter level.RGCI
Renal pelvis level: renal artery
Abdominal level: gonadal artery (testicular/ovarian)
Pelvic level: common iliac artery
Intramural level: internal iliac artery
What is the lymphatic drainage of the ureter?
Para-aortic lymph nodes
What is the innervation to the ureter?
Ureteric plexus in T11-L2, derived from renal, aorticorenal and superior and inferior hypogastric plexus.
T11-L2 is the sympathetic innervation.
S2-S4 for parasympathetic innnervation.
What is the sympathetic innervation of the ureter?
T11-L2
What is the parasympathetic innervation to the ureter?
S2-S4
How does urine enter bladder?
Enters the base of the bladder, partially covered by peritoneum.
What are the features of the bladder?
Contains rugae in bladder wall in order to expand and avoid changes in internal pressure.
What is the bladder trigone?
Triangular shaped region at the bladder base. It is formed by the openings of the ureter posteriorly in the bladder and the opening of the urethra.
What are the features of the trigone?
It has a smooth surface due to its mesodermal origin, as well as being less mobile and more sensitive to pain. The rest of the bladder is endodermal origin.
What is the lymphatic drainage of the bladder?
Para-aortic nodes and internal iliac nodes
What affects sensation in the bladder?
Suppression of nerve impulses due to bladder being empty. Reduced pain sensation upon empty bladder.
Parasympathetic innervation to the bladder
S2-S4
Stimulates the contraction of the detrusor muscle for bladder contraction. Inhibits the external urethral sphincter for micrutition.
Sympathetic innervation to the bladder
T10-L2.
Inhibits impulses to detrusor muscle to allow relaxation and storage of urine in bladder. Stimulates the external sphincter to prevent micrutition.
What is the innervation to the urethra?
Branches of the Inferior hypogastric plexus. This plexus is posterior to the urinary bladder:
Pudendal in females
Prostatic plexus in males
Innervation to male urethra?
Sympathetic, parasympathetic and visceral is delivered by the prostate plexus, a branch of the inferior hypogastric plexus which also controls the urethral sphincters.
What are the components of the male urethra?
Prostatic urethra: prostatic tissue surrounded by transitional epithelia
Membranous urethra: pseudostratified columnar epithelia and passes through the external urethral sphincter
Spongy urethra: surrounded by corpus spongiosum and transitions from pseudostratified columnar -> stratified squamous in glans penis
What is the lymphatic drainage of male urethra?
Internal iliac and deep inguinal nodes
What is the female urethra?
Much shorter than the male urethra and opens into a vestibule anterior to the vaginal opening.
What is the composition of the female urethra?
3 coats
Muscular coat: continuous with the detrusor muscle
Erectile coat: Surrounded by corpus spongiosus
Mucosal coat: Formed of stratified squamous epithelia which can produce mucus
What is the histology of the female urethra
Begins as transitional epithelia
-> Pseudostratified columnar
-> Stratified columnar
->Stratified squamous at external urethral orificie
What is the innervation of the female urethra?
Branch of the inferior hypogastric plexus -> pudendal nerve. This also controls the external urethral sphincter.
What is the lymphatic supply to the female urethra?
Internal and external iliac nodes.
What are the cells of the prostate?
Fibroblasts for supportive structure
Glands for semen production
Muscle cells for control of flow of ejaculation/urine
What is the largest zone of the prostate?
Peripheral zone where carcinomas are most likely to occur
What is the arterial supply to the prostate?
Inferior vesical artery
What is the venous drainage of the prostate?
Prostatic venous plexus into internal iliac vein
When does adenomatous prostatic growth occur?
Type of BPH where adenoma forms in the stromal/epithelial cells around age 30.
What drives Benign prostatic hyperplasia?
Aging increases levels of 5-alpha reductase for depletion of testosterone levels via catalysing:
testosterone -> dihydrotestosterone
or
Testosterone -> Oestrogen
What drives prostatic cell growth?
Most potent is dihydrotestosterone. Oestrogen has a lesser effect.
Consequences of BPH issues?
Filling issues and Voiding issues
What are the filling issues?
Increased frequency and urgency of urination, dysuria and nocturia
Why does terminal dribbling occur?
Weakness of pelvic muscles surrounding urethra.
-> occurs due to continuous straining of bowels, overweight, constant cough, prostate surgery.
Why does incomplete voiding occur?
Damage to the cauda equina that can also cause incontinence
Pelvic splanchic nerve damage
What causes poor stream?
Overactive bladder which increases urge
Enlarged prostate with compression of urine outflow
Why does decreased urination frequency occur?
Dehydration
Shock
Enlarged prostate- preventing urinary flow
Expanding haematoma- prevents flow
Tumour compression
Why does hesitancy of urination occur?
Enlarged prostate/prostate infection
What causes elevated PSA?
UTI
Prostatitis
Benign prostatic hyperplasia
Prostate cancer
What is sensitivity?
Proportion of true positives that are identified.
True positives/ True positives + false negatives
What is specificity?
Proportion of true negatives that are identified
True negatives/ True negatives+ false positives
What is the ROC curve?
Plot of the true positive against the rate of false positives
Why is sensitivity important?
Important in patient diagnosis to avoid unneeded interventions or treatment that may cause harm
Symptoms of cystitis
Dysuria, polyuria and urge to urinate
Symptoms of pyelonephritis
Accompanies symptoms of cystitis with fever, flank pain, nausea and vomiting
Symptoms of cystitis in children
Fever, onset of urinary incontinence
Infants will feed poorly, vomit, sleep more and show jaundice signs.
Symptoms of cystitis in elderly
Change in mental status such as confusion, fatigue and there may be incontinence.
Features of E.Coli
Baccili gram negative anaerobic bacteria commonly found as part of gut microbiome
How is E.Coli introduced into the urinary tract?
Wiping back to front after defaecation
Anal intercourse
Switching from anal to vaginal intercourse
Bacterial cause of UTI
E.Coli, Staphylcoccus saprophyticus, Proteus
Staphylcoccus saprophyticus
Gram positive bacteria found in the female genital tract. Increased risk of UTI with sexual activity when this is displaced into the urethra.
Proteus
Gram negative baccili bacterium found in soil and water. Once establishing UTI, commonly ascends up urinary tract to kidney
What is the diagnostic criteria for UTI?
Urinalysis for RBC, WBC, nitrites or leukocyte esterase
Urine culture for bacterial cause
Treatment of UTI?
Antibiotics such as trimethoprim + sulfamethaxodaole
BPH risk factors
Increasing age, obesity, family history and inactivity.
Driven by levels of dihydrotestosterone and oestrogen.
Consequences of BPH
Reduced urine flow which leads to:
Bladder stones and bladder failure
Urination issues with voiding and storage
Urinary retention
Dietl’s crisis
Episodic pain in the flank due to pelvi-ureteric obstruction
Testicular cancer pathology
Most commonly germ cell tumour. This is divided into seminomatous and non-seminomatous
Lymphoma and secondary metastases
Prostate cancer pathology
Malignancy with glandular origin in the acinar or ductal epithelia which originates in the peripheral zone, lesser in the transitional zone and central zone.
Renal abscess
Caused by haematogenous spread of UTI
Orchitis
Inflammation of the testicles due to mumps virus
