LM 1.4: Common Congenital GU Anomalies Flashcards
how is the phallice and urethra formed embryologically in men?
- genital fold, genital swelling, genital tubercle
- genital tubercle, genital fold, genital swelling
- glans, fused genital golds, anus
- urethral groove, scrotum (from genital swelling)
5.
how is the phallice and urethra formed embryologically in women?
- genital fold, genital swelling, genital tubercle
- genital tubercle, genital fold, genital swelling
- glans, unfused urethral groove, anus
- labia minor from genital folds, labia major from genital swellings
- clitoris, urethral orfice, hymen
what is hypospadias?
urethra opens onto underside of penile shaft, or at the penoscrotal junction or in the perineum
caused by failure of fusion of the ventral urethral groove
foreskin may appear as a dorsal hood
associated with chordee (curved penis)
extremely rare in girls; urethra opens into vaginal introitus
why is it important to identify hypospadias?
- circumcision procedures should be delayed in these infants, since the foreskin is often used in reconstruction
- surgical intervention is typically done within the first 2 years of life (most often between 6 and 24 months).
what is epispadias?
urethra opens onto the dorsal surface of the glans, or on the penile shaft or at the penopubic junction
most severe form occurs with bladder exstrophy = rare birth defect; bladder develops outside of the body through an opening on the adominal wall)
extremely rare in girls; urethra may open between the clitoris and labia, or in the abdomen
what is chordee? what causes it?
fotational curvature of the penis (ventrally, laterally, or rotationally) that becomes more apparent with erection
caused by fibrous tissue along the course of the corpus spongiosum or by a variation in the sizes of the two corpora
may be associated with hypospadias
what is the most common penile anomaly?
phimosis
what is phimosis?
constriction of the foreskin with inability to retract over the glans aka you can’t pull the foreskin down from the glans of the penis
can be congenital or acquired
may be “treated” or relieved with circumcision procedure
this is the most common penile anomaly!!!
what is paramphimosis?
inability to reduce a retracted foreskin distally over the glans aka you can’t put the foreskin back over the glans of the penis
should be reduced immediately (can act as a “tourniquet”, causing edema or pain)
may require circumcision
what is urethral mental stenosis?
narrowing of the opening of the urethra at the external meatus; can limit bladder outflow
most commonly “acquired” after circumcision but can be occasionally congenital (often associated with hypospadias)
meatotomy may be needed for difficulty with urinary stream
what is urethral stricture?
narrowing of the urethra internally; restricts urinary flow
what causes urethral stricture?
- straddle injuries
- pelvis fractures
- catheter insertion
- radiation
- benign prostatic hyperplasia
- prostate surgery
- untreated UTI (rare)
- untreated STD like gonorrhea or chlamydia (rare)
what is microphalus?
a stretched penile length < 2.5 standard deviations below the mean for age
penis is otherwise normally formed
associated with androgen deficiency or insensitivity; treatment is testosterone supplementation
A 27 year old male who races motorbikes professionally presents for evaluation of “difficulty with urination”. He reports that over the past 6 months, he often has difficulty starting his stream, and often feels that he cannot empty his bladder completely. What is the most likely etiology of his symptoms?
A. hypospadias
B. epispadias
C. meatal stenosis
D. urethral stenosis
E. enlargement of prostate
D. urethral stenosis
what are the most common testicular anomalies?
- congenital hydrocele
- undescended testes (cryptorchidism)
- testicular torsion
what is congenital hydrocele?
a collection of fluid in the scrotum between layers of the tunica vaginalis
may be communicating (through a patent processus vaginalis with the abdominal cavity–potential hernia space) or noncommunicating.
presents as painless, enlarged scrotum
often resolve spontaneously; usually requires repair if persists after 12 months of age (or if enlarging)
what is cryptorchidism?
aka undescended testes – failure of one or both testes to descend into the scrotum
often accompanied by an inguinal hernia
diagnosed by physical examination; confirmed by laparoscopy (if presence of testicle cannot be confirmed by exam) –> 2/3 resolve spontaneously within first 4 months of life
what is the pathophysiology of cryptorchidism?
the testes normally develop at 7-8 weeks gestation, then remain intraabdominal (above internal inguinal ring) until about 28 weeks gestation
at 28 weeks, they begin their descent into the scrotum guided by condensed mesenchyme called the gubernaculum
if this doesn’t happen, you get cryptorchidism
what hormonal, physical and environmental factors effect the descent of the testes?
hormonal
- androgens
- MIS
physical
- gubernacular regression
- intra-abdominal pressure
environmental
1. material exposure to estrogenic or antiandrogenic substances
what are true undescended testicles?
a form of cryptorchidism where the testes that remain in the inguinal canal along the path of descent
sometimes, less commonly, they’ll stay in the abdominal cavity or in the retroperitoneum
what is an ectopic testis?
a form of cryptorchidism where the testis descends normally but diverts to an abnormal location like the superficial inguinal pouch, perineum or inner aspect of the thigh
what is an empty scrotum?
a form of cryptorchidism where the testes do not end up in the scrotum
sometime the men will have palpable testes at birth but the ascending” with linear growth due to ectopic fubernacular attachment
what are the complications of cryptorchidism?
- subfertility
- testicular carcinoma
- testicular torsion
- inguinal hernia (associated with patent processus vaginalis
how do you diagnose cryptorchidism?
all newborn boys should have a testicular exam
annual examinations thereafter should assess testicular location and growth
an enlarged (larger than expected) unilateral descended testis should raise suspicion of an atrophic undescended testis
how do you treat cryptorchidism?
consider possibility of sexual differentiation disorder in presence of bilateral undescended testes.
treatment with surgical orchiopexy (testis is brought into the scrotum and sutured into place; inguinal hernia is repaired) for undescended testis should be done early (at about 6 months of age) to improve fertility and reduce cancer risk
if atrophic tissue is found on laparoscopy, the tissue is removed. (atrophic, undescended testes may be result of prenatal testicular torsion)
no intervention necessary for retractile testis if they rest without traction when cremasteric reflex not stimulated – these typically resolve without treatment by puberty with increased testicular size (makes retraction more difficulty)
what is testicular torsion?
when a testicle rotates, twisting the spermatic cord which contains the blood supply to the scrotum, reduced blood flow causes sudden and often severe pain and swelling
- sudden, severe pain in the scrotum, often with swelling
- abdominal pain, nausea and vomiting
- fever
- frequent urination
- may awaken in the middle of the night with symptoms
what are the complications associated with testicular torsion?
- damage or death to the testicle when unrecognized or not treated immediately
- permanent damage to the testicle may result in decrease in fertility
what are the risk factors for testicular torsion?
- vigorous activity
- minor injury to the testicles
- cold temperatures
- rapid growth (during puberty)
- family history may also play a role
how can you prevent testicular torsion?
surgical “anchoring” of testicles at risk for torsion
some men will have intermittent symptoms of torsion/ detorsion, which may predict increased future risk
You are examining an 18 month old male during a routine well child examination. You are unable to palpate the right testicle within the scrotal sac, although you believe that you can possibly palpate it high within the inguinal canal. A previous record documented bilateral descended testicles during his 12 month examination. What would you tell the parents about this findings during this visit?
A. this abnormality was present on previous examinations even though it was not documented as such
B. the child should be referred to a surgical specialist for evaluation for correction at this point
C. the child should be assessed by you against at the age of 2 and if this abnormality is still present he should be sent for evaluation by surgical specialist
D. the child should be prescribed hormonal therapy for 12 months and if no descent of the testicle then he should be sent for surgical evolution
B. the child should be referred to a surgical specialist for evaluation for correction at this point
PCPs should refer boys with acquired cryptorchidism after 6 months to a surgical specialist for timely evaluation
when does the female genital tract begin to develop? when do disorders develop?
begins at 3 weeks of embryogenesis and continues into the second trimester of pregnancy
disorders of the vagina occur prior to birth, and are closely associated with anorectal malformations/ imperforate anus
development of the gonads occurs independently from that of the genital tract, so women may have congenital uterovaginal anomalies with normal ovaries and hormonal production
what is vaginal agenesis?
the vagina stops developing prior to birth, resulting in a shorter vagina, a partial vagina, or no vagina at all
also known as Müllerian agenesis or Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome
associated with other abnormalities of the reproductive tract (absence of, or anomalies, of the uterus, or renal abnormalities)
what is an imperforate hymen?
the thin membrane that surrounds the vagina (hymen) fails to open, thereby completely covering the vaginal opening and blocking menstrual blood flow
may present in adolescence with pelvic pain and primary amenorrhea
may have pain with bowel movements and difficulty with urination
treatment is surgical to create a normal vaginal opening
what is a septet hymen?
a band of extra tissue in the middle of the hymen causes 2 small vaginal openings instead of 1
surgical removal of the band can create a normal vaginal opening
what is a fusion anomaly of the GU tract?
in some cases, the urinary and genital tracts may open into a common channel in women
An infant born to a 22-year old female has ambiguous genitalia. Karyotyping reveals presence of a Y chromosome, and there is no uterus on pelvic examination. The absence of a uterus is due to the effects of which of the following substances in the fetal period?
mullerian inhibitory factor (MIS)
embryonic testis secretes testosterone and Mullerian inhibitory factor (MIF) –> MIF causes regression of paramesonephric ducts, which normally give rise to internal genitalia in females
testosterone causes development of male internal genitalia
what are some of the causes of ambiguous genitalia?
hormonal abnormalities during pregnancy may interrupt or disturb the fetus’s developing sex organs.
- lack of male hormones in genetic male or exposure to male hormones in genetic female
- timing of expression is also important
- mutations in certain genes can influence fetal sex development and can cause abnormal expression
- chromosomal abnormalities (missing or extra sex chromosome) can cause
sometimes cause is unclear (in up to 50% of 46,XY DSD cases)
what is congenital adrenal hyperplasia?
CAH is the most common cause of virilized XX infants = a condition in which a female develops characteristics associated with male hormones
the adrenal glands make excess androgens, but also abnormalities (underproduction or overproduction) of mineralocorticoids
what are 4 causes of congenital adrenal hyperplasia?
- 21-hydroxylase deficiency
- 11-β-hydroxylas deficiency
- P450 oxidoreductase deficiency
- 3-β-hydroxysteroid dehydrogenase type II deficiency
what is 21-hydroxylase deficiency?
the most frequent enzymatic defect causing congenital adrenal hyperplasia!
dlevated serum 17-hydroxyprogesterone
salt-wasting (hyponatremia) with hyperkalemia and hypotension (varying degrees)
at risk for adrenal crisis (life-threatening)
what is 11-β-hydroxylas deficiency?
second most common enzymatic defect causing congenital adrenal hyperplasia
elevation in 11-deoxycortisol; mild elevation in 17-hydroxyprogesterone
mild-moderately virilized genitalia
older children can present with hypertension and hypokalemia
salt-wasting and adrenal crisis are rare
what P450 oxidoreductase deficiency?
a rare cause of congenital adrenal hyperplasia
has features of both 21-hydroxylase and 17-alpha hydroxylase deficiencies
what is 3-β-hydroxysteroid dehydrogenase type II deficiency?
a rare cause of congenital adrenal hyperplasia
relatively mild virilization
present with symptoms of cortisol and aldosterone deficiency (vomiting, hyponatremia, hyperkalemia, volume depletion)
which tumors can cause congenital adrenal hyperplasia?
rarely a tumor can produce androgens:
- maternal luteoma
- theca-lutein cysts
- placental aromatase enzyme deficiency
what are the genetic female 46, XX disorders of sex development?
- congenital adrenal hyperplasia
- prenatal exposure to male hormones
- tumors
what are the genetic male 46, XY disorders of sex development?
- 5-α-reductase deficiency
- partial gonadal dysgenesis
- androgen insensitivity syndrome
- impaired testiicular development
what is 5-α-reductase deficiency?
a genetic male 46, XY disorders of sex development
defective conversion of testosterone to DHT = undermasculinization of genitalia
fully functioning Leydig and Sertoli cells = spermatogenesis is possible
AR
what is partial gonadal dysgenesis?
a genetic male 46, XY disorders of sex development
likely a gene mutation results in abnormality of primordial urogenital structures
high risk of malignant transformations
decision about sex of rearing can be complicated (especially if very underdeveloped genitalia in 46 XY
what is androgen insensitivity syndrome?
a genetic male 46, XY disorders of sex development
x-linked recessive
can be partial or complete expression
The most common cause of congenital adrenal hyperplasia results from a deficiency of an enzyme which will also, mostly likely result in which of the following in the affected individual?
A. hypernatremia
B. hyperkalemia
C. ambiguous genitalia in both males and females
D. congenital hyperglycemia
E. congenital hypertension
B. hyperkalemia
21-hydroxylase deficiency accounts for 90 percent of cases of congenital adrenal hyperplasia, and results in hyperkalemia (inability to excrete K+)
