Why would we give oral contraceptives to a woman with PCOS?
In PCOS, there is hypersecretion of LH. The LH acts on the theca cells to increase production of androstenedione (androgens), which results in hirsutism. The increased LH and lack of FSH also disrupts the regular menstrual cycle, leading to amenorrhea.
Oral contraceptives are pills that contain a combination of estrogen and progesterone. Supplementing these hormones can help regulate ovulation, as well as stop the hirsutism.
What is clomiphene?
Clomiphene is an estrogen receptor inhibitor. It can be used to stimulate ovulation in a person with anovulation.
Normally, the estrogen produced by the granulosa cells of the follicle inhibits the release of FSH (and LH) through feedback inhibition. By blocking the negative feedback of estrogen, the hypothalamic--pituitary--gonadal axis is stimualted, and LH and FSH secretion are increased. This leads to the maturation of a greater number of follicles.
Which cells in the male gonads secrete testosterone?
What are the effects of low testosterone in men?
(Everything is low with low T)
What type of pathogen is tinea cruris? What drug would you use to treat it? What is a side effect of this drug?
This drug directly inhibits testosterone synthesis
From what cells types do sex cord-stromal tumors arise?
Granulosa cells, theca cells, and fibroblasts.
These are a type of ovarian tumor
A 44 yo woman presents with ascites, pleural effusion and an ovarian mass. What is the mass? What is the name of her condition? How would you treat her?
The mass is a benign ovarian fibroma (a benign tumor of fibroblasts)
This woman has Meig's syndrome, which is the traid of ovarian tumor, ascites, and pleural effusion.
Removal of the tumor resolves the symptoms.
Where in the male gonad does spermatogenesis occur?
Spermatogenesis occurs in the seminiferous tubules.
Spermatogonia (2N) are located in the most basal part of the compartment; as the germ cells develops, it moves apically. Spermatids (N) are located in the most apical part of the seminiferous tubule.
(Sperm develop from the outside of the tubule inward, so basal-side cells are 2N and apical cells are N).
What is the classic presentation of a complete hydatidiform mole?
--highly elevated ß-hCG levels
--uterine size that is larger than predicted for the length of pregnancy
--snowstorm/bag of grapes appearance of uterus on ultrasound
What is the function of oxytocin?
Dilation of the cervix and contraction of the uterus during labor.
Let-down of milk during breastfeeding.
Where is oxytocin produced and secreted?
Produced in the cell bodies of the neurons in the paraventricular nucleus of the hypothalamus.
Secreted from the posterior pituitary.
Why might we treat a woman who has PCOS with spironolactone?
Spironolactone is an anti-diuretic as well as an anti-androgen. In PCOS there is andorgen excess; the spironolactone will block androgen signalling, and hopefully resolve the patient's hirsutism.
What is Kartagener's syndrome?
A defect in the dynein arm of microtubules that results in impaired ciliary function.
It can lead to:
recurrent upper respiratory tract infections
situs inversus (specifically, dextrocardia)
Generally speaking, what are p53 and Rb?
These are tumor suppressor genes that help regulate the cell cycle.
What is cryptorchidism?
Undecended testis (one or both)
What are the symptoms/consequences of cryptorchidism?
--Impaired spermatogenesis (sperm develop best a temperatures <37 degrees)
--increased risk for germ cell tumors, testicular cancer
--Leydig cells are unaffected, so testosterone levels can be normal
What is a varicocele?
An abnormal dilation of a testicular vein in the pampiniform plexus due to impaired drainage.
Most commonly affects adolescent and adult men.
On which side is varicocele most common? Why might there be a difference in incidence between the two sides?
The left side
The left gonadal vein drains into the left renal vein, which drians into the IVC, whereas the right gonadal vein drains directly into the IVC.
In the male, what does the genital tubercle develop into? Under the influence of what hormone?
The glans of the penis and the corpus cavernosum and spongiosum under the influence of DHT
In the female, what does the genital tubercle develop into, and under the influence of what hormone?
The glans clitoris and vestibular bulbs, under the influence of estrogen.
When do ß-hCG hormone levels peak?
They peak at around 9 weeks of gestation, and then decline until they reach a steady state around week 25.
What is the purpose of ß-hCG?
ß-hCG is secreted from the syncytiotrophoblast cells immediately after implantation in the endometrium to resuce the corpus luteum from regression, and to stimulate the continued production of progesterone and estradiol that are needed to maintain pregnancy.
What is hypospadias?
Opening of the urethra on the inferior surface of the penis.
Due to failure of the urethral folds to close.
What is the tunica vaginalis?
The tunica vaginalis is a serous membrane that covers the surface of the testicle and is reflected onto the internal surface of the scrotum.
What is hydrocele?
Fluid collection around the testicle within the tunica vaginalis.
What is the presentation of hydrocele? How is it diagnosed?
Presents as painless scrotal swelling that can be transilluminated.
A positive transillumination test suggests that the mass/swelling is fluid-filled.
What would be the physical exam sign for peritoneal irritation?
What is epispadias?
Abnormal opening of the penile urethra on the dorsal sied of the penis.
Due to faulty positioning of the genitcal tubercle.
What is the inferior 2/3 of the vagina derived from?
The vaginal plate of the urogenital sinus
What is androgen insensitivity?
A defect in the androgen receptor, causing them to be unresponsive to androgens.
Results in a normal-appearing female with female external genitalia; no uterus or fallopian tubes.
Testes do develop, and are often found in the labia majora. (surgically removed to prevent malignancy)
What hormone levels are observed in androgen insensitivity?
Testosterone, estrogen and LH are all increased.
What is the genetic complement (karyotype) of a person with androgen insensitivity?
How does ectopic pregnancy present?
Sharp lower abdominal pain
lack of observable intrauterine gestational sac by the time ß-hCG levels are 2000IU/L
List the locations of ectopic pregnancy in order of frequency
In what gonadal structure are spermatids made? Where do sperm gain their motility?
made: seminiferous tubules
gain motility: epydidymis
What kind of epithelium lines the epididymus?
pseudostratified columnar epithelia with sterocilia
What type of internal and external genitalia does a person with 5 alpha-reductase deficiency have?
--normal male internal genitalia (including testes)
--ambiguous or female-appearing external genitalia
(DHT is required for the development of male external genitalia in utero)
TSH, LH, FSH and ß-hCG all share the same alpha subunit. What confers each of these hormones their functional specificity?
Their ß subunits.
A 31 yo man presents with dysuria and purulent urethral discharge. Gram stain shows gram-negative diploccoci with leukocytes. What is the causative organism?
By what uniqu mechanism does gonorrhoeae evade the immune system?
It has variable antigenic pili.
These pili mediate its attachment to the host mucosal surfaces, but they are continually varied to evade host immune response. This make vaccine development against gonorrhoeae difficult.
What organism(s) are described by an ability to metabolize urea into ammonia and CO2?
This describes urease (+) organisms
What organism is described by having an extracellular form and an intracellular form capable of replication?
Can Chlamydia trachomatis be detected by gram stain?
It's an obligate intracellular bacterium that cannot be detected by gram stain.
How does primary syphilis present?
A painless chancre, no urethral discharge.
What organism is described by a helical shape and two membranes and two flagella?
Treponema pallidum, which causes syphilis.
What is the typical age range for testical cancer?
15 - 40 years old
What are two risk factors for testicular cancer?
Klinefelter's syndrome (47, XXY)
These risk factors are also associated with earlier age of onset, and finding the neoplasm at extragonadal locations
What is Fragile X syndrome?
An X-linked dominant disease caused by abnormal expansion of the CGG trinucleotide repeat.
What is the primary site of testicular cancer metastases?
The para-aortic lymph nodes.
The lymphatics of the testes drain into the para-aortic and lumbar lymph nodes.
What physical findings can be found in a baby born to a mother with syphilis?
What kind of cells line the ureters?
Describe the passage of the ureters from the kidney to the bladder.
The ureters run anterior to the external iliac artery before entering the pelvis. They then pass under the uterine artery in females and under the vas deferens in males ("water under the bridge") before connecting to the bladder.
Along what parts of the urogenital tract is transitional epithelium found?
From the renal pelvis to the urethra, including the bladder.
What is the mechanism of action for penicillin?
Penicillin antibiotics contain a ß-lactam ring, which binds to and inhibits the bacterial enzyme transpeptidase. This arrests cell wall synthesis and leads to bacterial cell lysis.
"String of pearls" on ultrasound of the uterus is pathognomonic for what condition? What do the string of pearls represent?
The string of pearls are ovarian cysts
For what cancer are patients with PCOS at increased risk for? Why?
PCOS is often characterized by high levels of estrogen (estrone, produced by peripheral conversion of androgens in adipose tissue, which are also inexcess). However, progesterone levels in PCOS are typically low, due to the disrupted ovulation/menstrual cycle 2º to high LH. High levels of estrogen that are unopposed by progesterone are a risk factor for endometrial hyperplasia and carcinoma.
Why is obesity a risk factor for endometrial carcinoma?
Endometrial carcinoma is an estrogen-dependent neoplasia. Anything that increases a person's exposure to estrogen, especially when unopposed by progesterone, increases that person's risk for endometrial carcinoma.
Adipose cells contain aromatase, which converts androgens to estrogen. Obesity increases this peripheral conversion, leading to increased esterogen levels.
What is the treatment for hypogonadism in a male? What are the side effects?
premature closure of the epiphyseal plates
male pattern baldness
What type of antibiotic is ciprofloxacin?
a broad-spectrum fluoroquinolone
Yellow-green, malodorous, frothy vaginal discharge with motile organisms on wet mount are indicative of what infection?
(a motile parasitic organism)
What drug would you use to treat Trichomonas vaginalis?
What are the side effects of metronidazole?
Disulfiram-like effect when combined with alcohol.
Besides azithromycin, what other antibiotic can be used to treat Chlamydia?
How would you confirm a diagnosis of Trichomonas vaginalis?
You would do a microscopic examination of the patient's discharge to confirm the diagnosis.
The presence of flagellated trophozoites on wet mount confirms the diagnosis.
What area of the prostate is the most common site for benign prostatic hyperplasia?
The transition zone
(the central periurethral zone)
Is parental consent for treatment mandated in the case of adolescent STDs or reproductive health care?
If an adolescent is diagnosed with gonorrhoeae, do you have to notify the public health department?
Yes. gonorrhoeae is a reportable infection in all 50 states.
What is the mechanism of action of metronidazole?
Induces formation of toxic metabolites in bacteria or protozoa
For what infection are clue cells pathognomonic? What are clue cells?
Clue cells are vaginal epithelial cells covered with bacteria.
What type of pathogen is Gardnerella vaginalis?
A pleomorphic gram-variable rod.
What symptoms characterize infection by Gardnerella vaginalis?
genital buring, itching, whitish-gray vaginal discharge with a fishy smell.
What do you use to treat Garnerella vaginalis?
How should you treat benign prostatic hyperplasia?
1. alpha-1 antagonist to relax smooth muscle
2. 5 alpha-reductase, to decrease the production of DHT
Why do all babies born in the US via vaginal delivery receive erythromycin eyedrops?
This is prophylatic treatment against Chlamydia trachomatis, which can cause conjunctivitis in a newborn 2º to passage through the birth canal.