Genitourinary System Flashcards
How any types of HPV are there, and how are they transmitted?
200 types, 40 types are transmitted sexually.
Can be high or low risk
How prevalent is HPV, and how is it typically treated?
80% of sexually active people come into contact with it.
Normally cleared within 8 months to 2 years.
People unable to clear it are at increased risk of pre-cancerous changes. Onset of tumours is typically 13 years
Describe the histological layout of cells at the cervix.
Cervical opening (cervical os), surrounded by endocervix (simple granular cuboidal cells containing musin) , then the ectocervix (squamous, stratified, only base layer should have evidence of cell division)
How does HPV enter the cervical cells to cause disease?
Abrasions to the ectocervix exposing basement membrane, where HPV cells can then enter cellular DNA
What are koilocytes?
The ectocervical cells in which HPV has caused changes.
Hallow appearance around nuclei, enlarged/multiple nuclei, raisenoid appearance
Define high risk HPV infections
Viral DNA is incorporated into the host genome
Contain viral E6 and E7 proteins responsible for reactivating cell cycle in layers above basement layer
Cause persistent infection, proliferation of epithelial cells, and precursor legions (CIN and CGIN)
Subtypes 16, 18, 31, 45, and more
Define low risk HPV infections
Result in free viral DNA within cell
Cause vaginal warts
i.e. 6, 11, 42, 44
What is CIN?
Cervical Intraepithelial Neoplasia
CIN1- typically resolves itself, monitoring needed. bottom (closest to basement membrane) 3rd of squamous epi.
CIN2- involves bottom 2 3rds of squamous epi. Being tested for in screening.
CIN3- precursor lesion for squamous cell carcinoma, what is being testing for. Involves full squamous epi layer. Typically takes 2 years to develop into invasive carcinoma.
What is CGIN?
Cervical Glandular Intraepithelial Neoplasia
Less common than CIN
Precursor lesion to adenocarcinoma
Endocervical epithelium
What outcomes are possible with cervical screening?
Fail- insufficient cells, retest in 3 months
Negative- Come back in 5 years
Positive- sample tested for cytology
What cervical cytology tests are used in labs and how does it work?
Thinprep process 1. Dispersion 2. Cell collection 3. Cell transfer This is not diagnostic.
What is dyskariosis?
Abnormal cell with enlarged nuclei
Graded from mild (CIN1), moderate (CIN2), and severe (CIN3), depending on nuclei size
Appear to have enlarged nuclei with irregular borders, smaller nucleus to cytosol ratio, darker blue, non-circular
What is colposcopy?
Examination of cervical cells within patient using microscope and speculum
Can use acetic acid to highlight abnormalities.
Can take biopsies to determine diagnosis
How many women in Scotland will develop breast cancer?
1 in 8
women 50-70 are invited to screening
What type of cells and tissue are found in breasts?
Centre has central ductal structure, with lobular structures surrounding it. This is the breast tissue, it’s surrounded by fibrous pale pink tissue, and lastly adipose, white tissue cells .
Each duct lined by two layers, inner are tall cuboidal cells, no mitotic activity, surrounded by basal layer which can be fragmented, with subtle smaller cells outside the ducts
What is pleomorphism?
Different appearance of the same cancer
What is the prevalence of bowel cancer in Scotland?
3rd most common, 4000 new cases every year, typically people over 50
5 year survival around 60%
What is involved in the bowel cancer screening?
50-74 years invited.
Faecal Immunochemical Test (FIT)
Tests for haemoglobin (most cancers cause bleeding)- if greater than 80ugHb/g.
1 in 50 are referred on for colonoscopy.
What are superficial and deep nephrones?
Nephrons live in the cortex of the kidney, but loop of Henle extends down into the medulla.
Superficial nephrons and juxtamedullary nephrons,
Juxtamedullary nephrons have loop which extends much more deeply into renal medulla and are better at water reabsorption
What drives ultrafiltration?
High pressure
Pushes 20% of blood fluid into nephron.
Filters 1.25L of blood/minutes, filtering ~90-140ml/min out of the blood flow into the nephrons.
What is active secretion in nephrons?
Active pumping into the tubules to excrete substances, like drugs, faster than blood is being filtered.
What is the filtration barrier in nephrons? Move from capillaries into Bowman’s capsule
Formed elements are unable to move through fenestrations in glomerulus capillaries.
Basement membranes contain negative charge (heparin sulphate glycosaminoglycan, draws positive molecules) and collagen 4/ laminins (lamina densa)
Simple squamous cells and podocyte cells.
Podocytes give off processes (nephrins) which interdigitate with each other, helping to filter blood.
What sort of compound are filtered at the renal corpuscle?
Small molecules, ions, urea, glucose, amino acids, small proteins (haemoglobin would find it a tight fit, but charge of it will keep it in blood)
How can filtration go wrong?
High pressure pushes large molecule through.
Inflammatory disease causing podocyte processes to move further apart allowing larger molecules to be filtered.
What is a normal glomerular filtration rate?
90-140ml/min
Discuss the membrane, solute movement, and volumes present at the Proximal Convoluted Tubules.
Continual epithelial cells
Brush border to increase surface area
Active reabsorption of glucose, amino acids, co-transport of Na, and K ions.
Channels allow high amounts of water reabsorption
Co-transporters, aqueous channels, and membrane pumps responsible for movement.
At end of PCT, complete reabsorption of glucose / amino acids, substantial Na reabsorption and water.
Volume of filtrate by end is reduced by 2/3ds (about 40ml left)
Describe solute movement and membrane thickness within the Loop of Henle.
Thin membrane
Contains thin descending mechanism, and a thick wall for the ascending membrane due to solute pumping which creates counter-current mechanism that ‘recycles’ solutes.
No net reabsorption because solutes being pumped out enter into descending tubule of loop.
What is the significance of the ascending portion of the loop of Henle?
Solute pumping out of filtrate, like Na and Cl
Thicker membrane
Creates recycling of solutes, and osmotic pressures.
Describe the distal convoluted tubule, including its membrane, purpose, and how it differs from the proximal convoluted tubule.
Relatively thick walls with no brush border.
Similar job to proximal tubules, but at smaller level.
No glucose transporter.
Less electrolytes/water reabsorption.
Ion pumping is controlled by hormones, meaning Na and K exchange can be fine tuned.
What important features are found in the collecting duct in relation to water flow?
Not very active cells. Largely water proofing, but this is controllable.
Collecting duct moves down past loop of Henle where there is high osmotic pressure, causing final withdrawal of water.
Permeability is controlled by anti-diuretic hormone (AVP),
How does Anti-Diuretic Hormone/ AVP control water movement?
Aquaporins are made and stored in cell, they will be inserted into luminal membrane following anti-diuretic hormone (AVP) release, which will allow for water reabsorption of collecting duct.
Can have rapid insertion/removal of them.
What is diaresis and how is it impacted by hormones?
Increased urine production
Starts 15-20 minutes following ADH/AVP is released (when hormone half-life is reached), removing aquaporins from luminal membrane, causing filtrate to move straight to bladder
What is typical osmolarity of normal plasma?
300 mOsm (in textbooks may say 275-290)
What happens in regards to hormone release if plasma osmolarity is high?
Is rises, detected by osmotically sensitive cells in hypothalamus, causing increase in ADH/AVP secretion from the anterior pituitary gland. (i.e. makes more concentrated urine).
ADH causes more insertion of aquaporins within collecting duct, allowing for more water reabsorption.
What is the maximum concentration and max/minimum output of urine?
~1200mOsm
1mL/sec minimum
20mL/sec
What is the half life of ADH?
15-20 minutes
What is the juxtaglomerular apparatus?
Collection of cells within the distal convoluted tubule (where the tube curves back to meet the glomerulus) and glomerulus that sense hypo-filtration and can begin secretion of renin
How does renin influence blood pressure?
It splits angiotensinogen into angiotensin 1, which is later converted into angiotensin 2, which causes vasocontraction, resulting in increased blood pressure.
How does the sympathetic nervous system work within the kidney?
Sympathetic nerve innervation can activate the angiotensin/renin system to enhance its effectiveness and increase vasoconstriction.
What is aldosterone?
Steroid hormone that increases when electrolyte concentrations fall.
Makes additional sodium pumps in cells, resulting in increased reabsorption of Na within the loop, distal convoluted tubule, and duct cells
What secrete aldosterone?
The glomerulosa cells of the adrenal cortex
What ions does aldosterone influence?
Increases Na reabsorption
Increases Cl reabsorption
Secondary action- Increases K secretion (it swaps it for sodium)
Increases absorption of Na from gut, and reduced secretion of Na in sweat and tears
How does urine move along the ureter?
Peristalsis at about 1-2mm/second
How is urine flow from bladder regulated?
Sphincters
What is a cystometrogram?
Measuring the functioning of the bladder.
Looking at pressure and filling of it
What does the bladder consist of in terms of anatomy?
Smooth muscle, within the wall it is called detrusor muscle.
More internally is a water-proof mucosal lining, internally is the ureteral orifice.
Trigone
Internal urethral sphincter (neck)- smooth muscle
External urethral sphincter
What are the pressure phases of micturition?
Storage and voiding
How do pressures change during storage phase of micturition in the bladder and sphincter/urethra?
Bladder- pressure very slowly increases during storage phases
Sphincter- pressure is already slightly higher than the bladder, but also slowly increases during storage.
Sensory neurons start to pick up on bladder stretching, which signals contraction of external sphincter in later storage.
Are the bladder muscles and sphincters contracted or relaxed during the storage phase of micturition?
Bladder is relaxed
Inner urethral sphincter is contracted
During later half of storage phase, external sphincter is contracted
Stimulation of what receptor would be used in treating incontinence?
Beta 3
B3 agonists cause relaxation of the detrusor muscle, allowing for bladder to fill more, increasing its capacity.
What are the nerve roots on the pudendal nerve?
S2-S4
The sympathetic nervous system acts on the inner urethral sphincter using what receptor?
Noradrenaline on an alpha 1 receptor.
This will stimulate contraction, and a lack of urinary flow
What nerve carries sympathetic innervation to the bladder?
Hypogastric nerve
What areas of the nervous system control the detrusor muscle, inner, and external urethral sphincters during voidance and storage?
Voidance- parasympathetic
Detrusor controlled by pelvic nerve release of acetylcholine onto M3, causing contraction.
Storage- Sympathetic and somatic
Detrusor and inner- Hypogastric release of noradrenaline onto b3 receptors or detrusor (cause relaxation), and alpha1 receptors of inner sphincter (cause contraction)
External Sphincter- Pudendal nerve release of acetylcholine onto nicotinic receptor of external sphincter (contraction)
What area in the brain is responsible for coordination of the sphincters and bladder?
The Pontine Continence Centre in the Pons.
Explain the nerves and receptors involved in coordinating urinary continence in the bladder and sphincter in relation to the sympathetic nervous system?
Pons Coordination -> innervation down sympathetic nuclei in spinal cord -> hypogastric nerve at T10-L2 -> Noradrenaline release -> stimulates B3 receptors of fundus, causing detrusor muscle relaxation/ A1 receptors on inner urethral sphincter causing contraction
How does the somatic nervous system contribute to the storage phase of micturition?
During storage phase, impulses from pudendal nerve cause acetylcholine release and stimulation of nicotinic receptors of external urethral sphincter, causing contraction.
During the voiding phase of micturition, what nerves are involved, and how so?
Parasympathetic nerves dominate
Pelvic Splanchnic Nerve releases acetylcholine which binds m3 muscarinic receptors of the detrusor muscle contraction
What happens to pressure on the bladder and internal/external urethral sphincters during the voidance phase of micturition?
Pressure increases, bladder contracts, and sphincters relax allowing for voluntary voidance, there is a voluntary stop of flow followed by second voluntary voidance.
Happens much quicker than storage phase.
In relation to increasing volume in the bladder, what types of sensations are supported by large/small myelinated/unmyelinated fibers?
Large, myelinated- lesser volumes cause feeling of fullness and desire to micturate.
Small unmyelinated- large volume in bladder give rise to discomfort and pain
What is the maximum bladder volume during storage phase, and maximal anatomical bladder capacity?
Volume: 350-550mL
Anatomical capacity: 400-600mL
At what volume does the first sensation and the first urge to urinate occur?
Sensation: 150-250mL
Urge: 350-550mL
What is the maximum micturition pressure during voiding?
Male: 90cmH2O
Female: 75 cmH2O
What is the maximum detrusor contraction pressure during voidance?
Male: 75 cmH2O
Female: 55 cmH2O
What is maximum urine flow during voidance?
Male: 20-25 mL/s
Female: 20-30mL/s
What is a neurogenic bladder?
Lack of control of bladder due to neurological problems.
What is an atonic bladder?
Someone doesn’t have an active sense of reflexes.
Bladder pressure rises slowly as the bladder fills, and need to urinate is not reached as quickly as it should.
The bladder muscles lack tonus
How does Benign Prostatic Hyperplasia impact micturition?
Increasing proliferation of transverse prostate size increases pressure, either on urethra, or on bladder, which can reduce trigone size increasing need to urinate, or can cause difficulty in allowing full emptying of bladder as urethra may have higher pressure and resistance to flow. This will increase urine flow time.
What type of pain do the parietal and visceral peritoneum respond to?
Parietal, outer layer- well localized pain. Sensitive to temperature, pain, laceration, and pressure.
Visceral, inner layer- surrounding organs, not localized to stimulus. Sensitive to stretch and chemical irritation
What innervation supplies to the visceral peritoneum?
Autonomic nerves supplying the viscera beneath it.
What germ layer is the visceral peritoneum derived from?
The splanchnic mesoderm
What are some intraperitoneal organs?
Stomach, spleen, liver, bulb of the duodenum, jejunum, ileum, transverse colon, and sigmoid colon
What type of membrane makes up the peritoneum?
Serous membrane consisting of mesothelium
Where are the kidneys located?
T12-L3, by ribs 11 and 12
Retroperitoneal
What are some retroperitoneal organs?
Oesophagus, kidneys, part of duodenum, descending colon, middle third rectum, pancreas, adrenal glands, proximal ureters, renal vasculature
What type of pain do the parietal and visceral peritoneum respond to?
Parietal, outer layer- well localized pain. Sensitive to temperature, pain, laceration, and pressure.
Visceral, inner layer- surrounding organs, not localized to stimulus. Sensitive to stretch and chemical irritation
What innervation supplies to the visceral peritoneum?
Autonomic nerves supplying the viscera beneath it.
What germ layer is the visceral peritoneum derived from?
The splanchnic mesoderm
What are some intraperitoneal organs?
Spleen, liver, stomach, some of the intestines (cecum, transverse colon, sigmoid colon), appendix
What type of membrane makes up the peritoneum?
Serous membrane consisting of mesothelium
Where are the kidneys located?
T12-L3, by ribs 11 and 12
Retroperitoneal
Right is lower
What are some retroperitoneal organs?
Oesophagus, kidneys, part of duodenum, descending colon, middle third rectum, pancreas, adrenal glands, proximal ureters, renal vasculature
How does filtrate move from the collecting ducts to form the ureter?
Renal pyramids empty filtrate into papilla, which join to form minor calyx form major calyx, they conjoin to form renal pelvis, which then forms the ureter
What is the horseshoe kidney?
When kidneys fuse during development, and the kidney therefore can’t migrate upwards, and so sits lower.
More common in males, typically asymptomatic.
What important features are found in the hilum of the kidney?
Renal artery
Renal vein
Ureter (formed at renal pelvis)
What important landmarks are on the kidney?
Cortex (functional components- bowmen’s capsule, glomerulus, convoluted tubules) and medulla (loop of Henle, collecting ducts) organized into pyramids
Superior and Inferior pole
What is the renal corpuscle?
Bowman’s capsule and glomerulus
What arteries supply the adrenal glands?
Inferior phrenic arteries (and diaphragm)
Superior suprarenal arteries
Middle suprarenal arteries
Inferior suprarenal arteries
What is a papilla?
The papilla link in to form the minor calyx
How does filtrate move from the collecting ducts to form the ureter?
Renal pyramids empty filtrate into papilla, which join to form minor calyx, they then form major calyx, they conjoin to form renal pelvis, which then forms the ureter
What is polycystic kidney disease?
Autosomal Dominant PKD- Affect 1 in 500
Autosomal Recessive PKD- Affects 1 in 20,000
Cyst formation in kidneys, destroyed parenchyma of kidney leading to kidney failure
Causes raised BP, headaches, abdominal pain
What is a FAST scan?
Type of imaging used in typically emergent situation.
bedside ultrasound that can be used to image blood (hemoperitoneum, abscess)
What is the Pouch of Morrison?
Space between the kidney and liver
What vessels supply the kidneys?
Renal arteries from abdominal aorta
What arteries supply the adrenal glands?
Inferior phrenic arteries branches into the Superior suprarenal arteries
From the aorta arises the middle suprarenal arteries and the inferior suprarenal arteries
What vessels drain the kidneys?
Renal vein typically anterior to the artery
Right drains directly into the inferior vena cava, and is shorter
Left crosses abdominal aorta to drain into the inferior vena cava
Where do the gonadal veins differ in drainage?
Left gonadal vessel drains directly into left renal vein
Right drains into the inferior vena cava
What is polycystic kidney disease?
Autosomal Dominant PKD- Affect 1 in 500
Autosomal Recessive PKD- Affects 1 in 20,000
Cyst formation in kidneys, destroyed parenchyma of kidney leading to kidney failure
Causes raised BP, headaches, abdominal pain
Describe the movement of sperm within the testes
Sperm passes into seminiferous tubules -> straight tubules -> stored temporarily in rete testes -> efferent ductules -> epididymis
What are the layers of the bladder wall, starting most superficial?
Detrusor muscle
Submucosa
Lamina propria
Transitional epithelium
What connects the testes to the urethra?
Vas deferens
What are the layers of the testicles, starting most internal, and moving outwards?
Tunica albuginea Visceral tunica vaginalis Parietal layer of tunica vaginalis Internal spermatic fascia Cremaster muscle and fascia (controls whether testes are lowered or not) External spermatic fascia Superficial fascia Skin of scrotum
How do testes develop in utero?
Begin development in abdomen, descend into scrotum around 7 months
What type of hormone secretion is found within the testes?
Exocrine secretion- sperm
endocrine- testosterone secretion
What are found within the tunica albuginea?
Tunica albuginea forms 200-300 lobules that contain 1-4 seminiferous tubules
Describe the movement of sperm within the testes
Sperm passes into seminiferous tubules -> straight tubules -> stored temporarily in rete testes -> efferent ductules -> epididymis
Describe the process of spermatogenesis.
Seminiferous tubules produce immature spermatozoa -> sperm matures in epididymis
What is the lifespan of sperm?
48 hours
What are the inguinal rings?
The ring in which testes move, from internal inguinal ring, down the canal, to the external ring.
What is cryptochidism?
Maldescent of testes. Can be located within inguinal canal, pre-scrotal, or abdominal. If bilateral, can cause infertility. 80% of cases have spontaneous descent 3% of full-term infants 90% premature
Where is the prostate found?
Below urinary bladder, superior/posterior to external urethral sphincter.
What are the different ways the uterus can sit anatomically?
Normally sits anteverted, anteflexed.
If cervix is pointing posteriorly, it is retroverted
If fundus is located posterior to cervix, it is retroflexed.
What is Hydrocoele?
Accumulation of fluid within the tunica vaginalis.
Penlight exam reveals translucent scrotum
Can be caused by trauma, but may need to be drained
What are the sections of the male urethra?
Prostatic
Membranous
Pendulous (spongy)
What is the urethral crest?
A small invagination of prostatic urethra that prevents sperm flow into the bladder
What is the prostatic utricle?
Blind ended structure, origin of where the vagina and uterus would have developed
What gland is found within the membranous urethra?
Bulbourethral glands (Cowper’s glands) secrete glycoprotein in mucous during arousal, which moves down the urethra to lubricate and remove debris
Where is the prostate found?
Below urinary bladder, above external urethral sphincter.
What are the different ways the uterus can sit anatomically?
Normally sits anteverted, anteflexed
If cervix is pointing posteriorly, it is retroverted
If fundus is located posterior to cervix, it is retroflexed.
What ligaments are within the female pelvis?
Round ligament- maintain forward orientation (anteflexion)
Broad ligament- acts as mesentery, minor role in holding uterus forward
Ovarian ligament- connect ovary and lateral aspect of uterus
Suspensory- contain blood supply to ovary
What is the rectouterine pouch?
Double fold of peritoneum between rectum and uterus.
Most inferior where infection an fluid can accumulate.
A cultosentesis can be performed to collect liquids
What way does a baby typically face prior to labour?
Cephalic (facing down)
Can use manoeuvre for breech babies called external cephalic version to try and turn them down.
What are the fimbriae?
Small, finger like projections that help the ovum move from the ovary to the fallopian tube
Where are most ectopic pregnancies located?
Ampulla within the fallopian tube (between the infundibulum (ovarian end) and isthmus (uterine end) of tube
What causes aldosterone secretion?
Angiotensin 2 presence (caused by low blood pressure) and low blood sodium causes the zona glomerulosa in the adrenal cortex to secrete aldosterone.
What does aldosterone do?
Stimulates genes to form proteins that increase activity of sodium potassium pumps that will increase sodium reabsorption
What is found in renal columns?
Cortical tissue
Contains nephrons which move around to drain into the renal papilla
What regions can the cortex of the kidney be divided into?
Medullary Rays- projections of medulla consisting of collecting ducts and loops
Cortical Labyrinths- renal corpuscle and convoluted tubules
What does the Macula Densa do?
Dense region of nuclei within the distal ct of the juxtaglomerular apparatus, where the tubule moves closely to the glomerulus, that detects sodium levels of filtrate in distal convoluted tubule
Will release prostaglandins in response to low [NaCl] to stimulate juxtaglomerular release of renin to help increase bp, while also decreasing afferent arteriole resistance, to help increase glomerular hydrostatic pressure and restore GFR.
What is the movement of blood through the renal cortex?
Renal Artery -> segmented artery -> interlobar artery -> arcuate artery -> interlobular artery -> afferent artery -> glomerulus -> efferent artery -> peritubular capillaries -> interlobular vein -> arcuate vein -> interlobar vein -> renal vein
What tissue surrounds the kidneys?
Renal fascia containing fibrous tissue
