Pathology of the reproductive tract Flashcards
What are the male and female chromosomes?
XX = female XY = male
How is male sex determined?
Sex determining region of Y
What are the male and female gonads?
Testis
Ovary
Name the ducts that develop into male and female reproductive organs
Paramesonephric duct = female
Mesonephric duct = males
Describe the development of male and female reproductive organs in the foetus
- At the caudal pole of the kidney you will have the gonad developing and you will also have pairs of ducts Paramesonephric and Mesonephric.
- In the embryo both ducts will develop and they tract down and will ultimately join the urogenital sinus.
- When the gonad differentiates into ovary and starts secreting female hormones the paramesonephric duct will develop into the uterine tubes and horns and the mesonephric duct will regress.
- On the male side, the mesonephric duct will differentiate into vas deferens and the paramesonephric duct will regress.
- These then fuse with the urogenital sinus which will either develop into a vagina in the female or a penis and scrotum in the male
The development of male reproductive organs is under the influence of which hormones?
Testosterone
Malarian inhibitory hormone
What are the 3 major categories of disorders of sexual development?
- Abnormal or missing chromosome
- DSD with normal female karyotype
- DSD with normal male karyotype
Define intersex
Ambiguous genitalia with features of male and female (tubular and / or external genitalia)
Define hermaphroditism
The presence of both ovarian and testicular gonadal tissue
Describe two examples of sex chromosomal disorders
- XO (Turner syndrome) or XXX: females with severe ovarian dysgenesis, hypoplasia and immature reproductive tract.
- XXY (Klinefelter’s syndrome): males with testicular hypoplasia
Male tortoiseshell cats are the result of?
XXY sexual chromosomal disorder (Klinefelter’s syndrome)
Describe an XX SRY negative disorder of sexual development
- Undifferentiated gonad which has the potential to differentiate into ovary and testis; ovotesticular
- Usually true hermaphrodite
- Phenotypically female with masculinisation
- Inherited in American cocker spaniel (AR)
- Associated with the polled gene in goats (polled intersex syndrome – PIS)
Describe the two XY SRY positive disorders of sexual development
- XY SRY-positive; testicular DSD with female phenotype (male pseudohermaphrodite). Lack of anti-malarian hormone
- XY SRY-positive; testicular DSD with male phenotype e.g. cryptorchidism where the testis don’t descend from the abdomen into the scrotum
What is the function of anti-malarian hormone?
AMH is the hormone that inhibits the female elements of the reproductive tract from developing so males are supposed to have this
Describe freemartinism
- Form of ovarian dysgenesis in cattle
- Fusion of placental vessels during pregnancy + sharing of blood between twins during early embryonic development (bone marrow chimeras)
- Ovarian inhibition of female twin = Sterile female twin from a set of heterozygotic twins
- Male unaffected.
Name some ovarian circulatory disorders
- Intrafollicular haemorrhage - physiological, during ovulation
- Traumatic haemorrhage
What is a cyst?
Fluid containing structure, lined by a normal epithelium
Describe ovarian follicular cysts
- Arise from secondary follicles that fail to ovulate, involute or luteinise
- Failure in LH release during oestrus
- Common in cattle and pigs + seen in dogs, cats, sheep + goats; very rare in horses
How do follicular cysts affect cattle?
- Multiple follicular cysts give rise to hyperoestrogenism
- Can lead to behavioural changes i.e. nymphomania
Where can primary ovarian neoplasms originate from?
- Surface epithelium
- Ovarian stroma: granulosa cells (lining cells of the follicle)
- Ovarian germ cells
Which ovarian cysts arise from the surface epithelium?
- Papillary cystadenoma: most common in bitches, can be multicentric + involve both ovaries
- Papillary cystadenocarcinoma
Describe ovarian papillary cystadenocarcinoma and its complications
• Occurs in older bitches • Invasive growth; - implantation on peritoneum - invasion + obstruction of lymphatic vessels + veins • Ascites; widespread distant metastases
What is the DDx for an ovarian papillary cystadenocarcinoma?
Mesothelioma = neoplasm of the lining cells of the peritoneal cavity
What is an adenoma?
Benign tumour of glands
Name the tumour arising from the gonadal stroma
Granulosa cell tumour
Which spp get granulosa cell tumours?
Cow, mare, dog, cat
Describe a granulosa cell tumour in a cow or mare
- Usually unilateral, benign, often very large
- Secretion of progesterone, oestradiol and/or testosterone
What are granulosa cell tumours associated with in dogs and cats?
Hyperoestrogenism
Describe the structure of a granulosa cell tumour
- Normal anatomy of the ovarian follicle = lined by granulosa cells
- When these cells become neoplastic they attempt to recapitulate that follicular structure – see abnormal follicular type structures which often dilate and become cystic
- Cyst is full of proteinaceous fluid +/- small amounts of blood
Name two tumours arising from germ cells
- Dysgerminoma
- Teratoma
Describe the features of a dysgerminoma
- Occur most often in older bitches
- Female counterpart to testicular seminoma in males
- Usually unilateral, 20% metastasise to regional LN + transcoelomically
- Germ cells are primitive cells – not differentiated
Describe the features of a teratoma
- Uncommon – mainly bitch + occ. mare / cow.
- Arise from multipotential cells that produce tissues from 2 or 3 embryological layers (ectoderm, mesoderm + endoderm). Produce mature tissue from all 3 embryological lineages all within the same mass
- Mostly benign but occasionally malignant (teratocarcinoma).
How does a teratoma appear grossly?
Get bits of skin, hair, tooth, bone, brain, intestine, anything The ovary (or testis) will be massively enlarged when you do the spay or castrate
What are some acquired abnormalities of uterine (fallopian) tubes?
- Hydrosalpinx
- Salpingitis
- Pyosalpinx
Define hydrosalpinx
Clear, watery fluid in tubes, due to obstruction either at abdominal or uterine ostium
Define salpingitis
Inflammation of the uterine tube due to ascending infection (cattle)
What are the 3 types of uterine displacement?
- Torsion
- Prolapse
- Rupture
Describe the features of uterine torsion
- Usually gravid uterus (pregnant state)
- Multiparous animals: can be in one horn
- With relaxation of uterine bands and foetal movements
- Elongated uterine horns in veterinary spp which are susceptible to torsion
- Acute passive congestion in the organ which is developing into a haemorrhagic infarction
Describe the consequences of uterine torsion in cattle
Whole organ -> congestion, haemorrhagic necrosis, foetal death
Describe uterine prolapse in veterinary spp
Cow: with post-parturient hypocalcaemia or after dystocia – tissue becomes friable so need to be careful when replacing
Endometrial hyperplasia occurs due to?
Result of excessive/ prolonged female hormonal stimulation
What hormones cause endometrial hypoplasia in different veterinary spp?
- Ungulates (hoofed mammals), rodents: oestrogens
- Dog, cat: progesterone acting on oestrogen-primed endometrium
Describe oestrogen mediated endometrial hyperplasia
- Hyperplasia = organ enlarges due to proliferation of cells (increase in number)
- Prolonged non-cyclic oestrogen stimulation or
- Excessive levels of circulating oestrogens
What are the effects of oestrogen mediated endometrial hyperplasia?
• Hypertrophy of myometrium
• Hyperplasia of endometrium -> cystic endometrial hyperplasia
• Hydrometra or mucometra
- Endometrial cells have the ability to divide so the endometrium grows through hyperplasia
Describe progesterone mediated endometrial hyperplasia
- Most common in bitches
- Cows in association with retained CL
- Predisposes uterus to infection + pyometra
- Progesterone stimulates glandular secretion
- In oestrogen-primed endometrium -> increased synthesis of progesterone receptors + enhanced effect of progesterone
What occurs in sequelae to inflammation of the non-gravid uterus?
- Septicaemia/toxaemia, pyaemia
- Metritis, pyometra
- Ascending infection (salpingitis; pyelonephritis)
What is pyometra and which spp are affected?
- Acute / chronic suppurative inflammation of uterus with large quantities of pus in lumen
- Bitch, queen: bacterial infection of cystic, hyperplastic endometrium (“cystic endometrial hyperplasia-pyometra complex”)
What are the non-specific causative agents of pyometra?
E. coli, Proteus, Staphylococcus, Streptococcus
How does the cervix affect a pyometra
Can be open or closed, disease more severe with a closed cervix due to accumulation of purulent material
What are the consequences of pyometra?
Bacteria can enter bloodstream -> toxic shock and DIC
How does pyometra present grossly?
Brown, foul smelling purulent material within the uterus
Very enlarged uterine horns under pressure
Describe pyometra in cattle
Persistent CL due to failure of PGF2alpha (no luteolysis) -> continued progesterone secretion + decreased myometrial contraction with +/- closed cervix
Describe pyometra in mares
- Postpartum infection independent of persistent CL
- Often discharge observed
- Commonly isolated: Streptococcus zooepidemicus, E. coli, Pseudomonas aeruginosa, Pasteurella
What occurs in sequelae to pyometra in cattle and mares?
- Resolution (often through vet intervention + PGF2alpha administration).
- Metritis - toxaemia/septicaemia
- Rupture of the uterus with peritonitis
Name two primary tumours of the uterus
- Leiomyoma
- Adenocarcinoma
Where does a leiomyoma arise from?
Smooth muscle cells of myometrium + also vagina, cervix
Describe the features of a leiomyoma
- Made up smooth muscle: spindloid cells with cigar shaped nuclei
- Most frequent uterine neoplasm in bitch + cat
- Space occupying lesion
- Variation: leiomyosarcoma - locally invasive
Describe uterine adenocarcinoma
- Tumour of endometrial glands
- Frequent in older rabbits (>2y; 60% >4y) often multiple, metastasise frequently
- Occasionally seen in cows
