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.