USMLE - Reproduction Part 3

SRY produces testes determining factor
Sertoli cells secrete Mullerian Inhibitory Factor.
Leydig cells secrete Testosterone that stimulate development of mesonephric ducts

Mullerian Duct
Fallopian tubes, uterus, upper vagina
Primary amenorrhea with fully developed secondary sex characteristics

Wolffian duct
"SEED"
Develops into Seminal vesicles, Epididymis, Ejaculatory duct, Ductus deferens

Incomplete fusion of Mullerian duct

| Can lead to urinary tract abnormalities and miscarriages

Promotes development of male external genitalia and prostate

Development of both male and female internal genitalia and male external genitalia

XY
Internal genitalia normal
AR
Inability to convert T to DHT
Ambiguous genitalia until puberty, when T causes masculinization and ↑ growth of external genitalia
T and Estrogen levels are normal. LH normal or ↑

Male: Glans, Corpus Cavernosum, Spongiosum
Female: Glans Clitoris, Vestibular Bulbs

Bulbourethral glands, Prostate

| Greater vestibular glands of Bartholin and Urethral and Paraurethral glands of Skene

Ventral shaft of penis (penile urethra)

| Labia Minora

Scrotum

| Labia Majora

"Hypo is Below"
Abnormal opening of penile urethra on inferior (ventral) side of penis
Due to failure of urethral folds to close
More common than epispadias
Fix to prevent UTIs

"When you have Epispadias you hit your Eye when you pEE"
Abnormal opening of penile urethra on superior (dorsal) side of penis
Due to faulty positioning of genital tubercle
Extrophy of the bladder

Band of Fibrous Tissue
Anchors Testes within scrotum
Ovarian ligament and Round ligament of the uterus

Evagination of peritoneum
Forms tunica vaginalis
Obliterated

L ovary/teste --> L gonadal vein --> L renal vein --> IVC

| R ovary/teste --> R gonadal vein --> IVC

Para-Aortic Lymph Nodes

Superficial Inguinal Nodes

Obturator, External Iliac and Hypogastric Nodes

More common on Left because L venous pressure > R venous pressure because L spermatic vein enters L renal vein at 90 degrees, so flow is less continuous on Left

Ovaries to lateral pelvic wall

| Ovarian vessels

Ureter is at risk during ligation of ovarian vessels in oophorectomy

Cervix to side wall of pelvis

| Uterine vessels

Ureter at risk of injury during ligation of uterine vessels

Uterine Fundus to Labia Majora
Artery of Sampson
Derivative of Gubernaculum
Travels through round inguinal canal

Uterus, Fallopian Tubes, and Ovaries to Pelvic side wall
Ovaries, Fallopian tubes, Round ligaments of the uterus
Mesosalpinx, Mesometrium, Mesovarium

"Latches ovary to Lateral uterus"
Medial pole of ovary to lateral uterus
None
Derivative of gubernaculum

Stratified Squamous Epithelium, Nonkeritinizing

Stratified Squamous

Simple Columnar

Simple columnar, Pseudostratified tubular glands

Simple columnar, ciliated

Simple cuboidal

"SEVEN UP"

Seminiferous tubules

Epididymis

Vas deferens

Ejaculatory duct

Nothing

Urethra

Penis

Parasympathetic nervous system
Pelvic nerve
NO --> ↑ cGMP --> smooth muscle relaxation --> vasodilation --> proerectile

NE --> ↑ [Ca] --> smooth muscle contraction --> vasoconstriction --> antierectile

Sympathetic nervous system

| Hypogastric nerve

Visceral and Somatic Nerves

| Pudendal nerve

Maintain germ pool
Produce Primary Spermatocytes
Line seminiferous tubules

Secretes inhibin (inhibits FSH), Androgen binding protein (maintains local levels of testosterone), AMH

Tight junctions form blood-testis barrier --> isolate gametes from autoimmune attack

Support and nourish spermatozoa, Regulate spermatogenesis

Temp sensitive: Varicocele or Cryptorchidism --> ↑ Temp --> ↓ sperm production and ↓ inhibin

Secrete Testosterone

Unaffected by Temp

Interstitium

Spermatogonium (2N2C) --> Primary Spermatocytes (2N4C)--> [Meiosis I] --> Secondary Spermatocyte (1N2C) --> [Meiosis II] --> Spermatid (NC) --> [Spermiogenesis] --> Mature spermatozoon

Between Spermatogonium and Primary Spermatocytes

2 months

Loss of cytoplasmic contents and gain of acrosomal cap

Hypothalamus --> GnRH --> AP --> FSH and LH
FSH --> Sertoli cells --> ABP and Inhibin
Inhibin --/ AP
LH --> Leydig cells --> Testosterone --/ Hypothalamus and AP

DHT > Testosterone > Androstenedione

| T and D from testes, AnDrostenedione from ADrenal gland

Differentiation of epididymis, vas deferens, seminal vesicles (internal genitalia except prostate)
Growth spurt (penis, seminal vesicles, sperm, muscles, RBCs)
Deepening of voice
Closing of epiphyseal plates (via estrogen converted to testosterone)
Libido

Differentiation of penis, scrotum and prostate

| Prostate growth, balding, sebaceous gland activity

Aromatase in adipose tissue

XXY
Dysgenesis of seminiferous tubule --> ↓ inhibin --> ↑ FSH
Abnormal Leydig cell function --> ↓ testosterone --> ↑ LH --> ↑ Estrogen
Testicular atrophy, eunuchoid body shape, Tall, Long extremities, Gynecomastia, female hair distribution, Developmental delay
Barr body

XO
↓ estrogen --> ↑ LH and FSH
Short, shield chest, amenorrhea, menopause before menarche
Streak ovaries, bicuspid aortic valve, defective lymphatics --> webbing of neck (cystic hygroma), lymphedema in feet and hands, Preductal coarctation of the aorta, horseshoe kidney
Dysgerminoma
No barr body

Phenotypically normal, very tall, severe acne, normal fertility
Antisocial behavior and autism spectrum disorder

Testosterone ↑

| LH ↑

Testosterone ↑

| LH ↓

Testosterone ↓

| LH ↑

Testosterone ↓

| LH ↓

XX
Ovaries
Virilized or ambiguous genitalia
Exposure to androgens during early gestation: congenital adrenal hyperplasia or exogenous administration

XY
Testes
Female or ambiguous
Androgen insensitivity syndrome is most common form

XX or XXY
Ovotestis
Ambiguous genitalia
Very rare

Defective Androgen Receptor
Normal appearing female with female external genitalia but with scant genital hair
Rudimentary vagina. No Uterus or Fallopian tubes
Testes in Labia Majora that must be surgically removed
↑ Testosterone, Estrogen, and LH

Defective migration of GnRH cells and formation of olfactory bulb
Anosmia and lack of secondary sex characteristics
↓ GnRH, FSH, LH, T, and Sperm count

Premature detachment of placenta

DIC

Smoking, HTN, Cocaine

Painful bleeding in 3rd trimester

Life threatening for both fetus and mother

Defective decidual layer allows placenta to attach to myometrium --> No separation of placenta after birth
Prior C section, Inflammation, Placenta previa
Massive bleeding after delivery

Attachment of placenta to lower uterine segment over internal cervical os
Multiparity and prior C-section
Painless bleeding in any trimester

Postpartum hemorrhage and ↑ risk of infection

Fallopian tube
Amenorrhea, lower than expected ↑ in hCG, sudden abdominal pain w/ or w/o bleeding
US
Infertility, PID, Rupture appendix, Tubal surgery
Appendicitis
Endometrial biopsy shows decidualized endometrium but no chorionic villi

More than 1.5L
Esophageal/Duodenal atresia --> inability to swallow amniotic fluid
Anencephaly

Less than .5L
Placental insufficiency, bilateral renal agenesis, or posterior urethral valves (in males) leading to inability to excrete urine
Potters Syndrome

Inflammation of the endometrium with retained products of conception following delivery (vaginal, C-section, miscarriage, abortion, foreign body) leads to bacterial infection from vaginal or intestinal flora
Gentamycin + Clindamycin w/ or w/o Ampicillin

Endometrial > Ovarian > Cervical

| Ovarian > Cervical > Endometrial

Premature atresia of ovarian follicles
Menopause before age 40
↓ estrogen, ↑ LH, ↑ FSH

Pregnancy, PCOS, Obesity, HPO axis abnormalities, Premature Ovarian Failure, Hyperprolactinemia, Thyroid disorders, Eating disorders, Cushing's syndrome, Adrenal Insufficiency

Distention of unruptured graafian follicle
Hyperestrinism and Endometrial Hyperplasia
Most common ovarian mass in young women

Hemorrhage into persistent corpus luteum

| Commonly regresses spontaneously

Bilateral and multiple
Gonadotropin stimulation
Choriocarcinoma and moles

Blood vessel rupture into cyst wall.
Cyst grows with ↑ blood retention
Usually self resolves

Mature teratoma. Cystic growth with various tissues such as fat, hair, teeth, bone, cartilage

Endometriosis within ovary with cyst formation
Varies with menstrual cycle
When filled with dark, reddish brown blood it is called a chocolate cyst

Lobules --> Terminal duct --> Major duct --> Lactiferous sinus --> Nipple

Small, Mobile, Firm Mass with sharp edges
Most common tumor in those under 35
↑ size and tenderness with ↑ estrogen
Not a precursor to breast cancer

Small tumor
Lactiferous ducts, typically beneath areola
Serous or bloody nipple discarge
Benign with slight risk of carcinoma

Large and Bulky

Connective tissue and Cysts

Leaf-like projections

Most common in 6th decade of life

Some may become malignant

Common postmenopause
Terminal duct lobular unit in upper outer quadrant
Estrogen/Progesterone receptors or c-erbB2 (HER2 an EGF receptor)
Axillary lymph node involvement is important prognostic factor
↑ estrogen, total # of menstrual cycles, older age at 1st live birth, obesity, BRCA1, BRCA2 mutation

Noninvasive malignant breast tumor
Fills ductal lumen
Arises from ductal hyperplasia
Early malignancy w/o basement membrane penetration

Noninvasive malignant breast tumor
Subtype of DCIS
Ductal
Caseous Necrosis

Invasive malignant breast tumor
Firm, fibrous, "rock hard" mass with sharp margins
Small, glandular, duct-like cells with classic stellate morphology
Most common (76%)
Worst and most invasive

Invasive malignant breast tumor
Bilateral with multiple lesions in the same location
Orderly row of cells (Indian File)

Invasive malignant breast tumor
Fleshy, Cellular, Lymphocytic infiltrate
Good prognosis

Invasive malignant breast tumor
Dermal lymphatic invasion by breast carcinoma blocking lymphatic drainage
Peau d'orange (breast skin resembles orange peel)
50% survival @ 5 years

Eczematous patches on nipple
Paget cells = large cells in epidermis with clear halo
Suggets underlying DCIS
Also seen on vulva

Most common cause of breast lumps from 25 to menopause
Premenstrual breast pain and multiple bilateral lesions. Fluctuations in size of mass
Does not indicate risk of carcinoma

Fibrosis: hyperplasia of breast stroma
Cystic: Fluid filled, blue dome. Ductal dilation
Sclerosing adenosis: ↑ acini and intralobular fibrosis. Calcification. Often confused with cancer
Epithelial hyperplasia: ↑ # of epithelial cell layers in terminal duct lobule. ↑ risk of carcinoma with atypical cells. Occurs in women over 30

Breast abscess
During breast feeding
Risk of bacterial infection through cracks in nipple by S aureus

Benign
Painless lump
Injury (usually unreported)

Hyperestrogenism (Cirrhosis, Testicular tumor, Puberty, Old age)
Klinefelter's Syndrome
Drugs (Estrogen, Marijuana, Heroic, Psychoactive drugs, Spironolactone, Digitalis, Cimetidine, Alcohol, Ketoconazole)
"Some Drugs Create Awkward Knockers"

Dysuria, Frequency, Urgency, Low back pain
Acute: bacterial (E coli)
Chronic: bacterial or abacterial (most common)

Men over 50
Nodular enlargement of periurethral (lateral and middle) lobes compresses urethra
Not premalignant

Frequency, Nocturia, Dysuria, Difficulty starting and stopping stream
Distention and Hypertrophy of the bladder, Hydronephrosis, UTIs
↑ PSA
α1 antagonists (Terazosin, Tamsulosin), Finasteride

Men over 50

Posterior lobe in peripheral zone

↑ PSA and subsequent biopsy

Prostatic Acid Phosphatase and PSA

Osteoblastic mets to bone present as lower back pain and ↑ AlkPhos