CRYPTOCHIDISMCryptorchidism is the most common genital problem encountered in pediatrics, refers to an un-descended or mal-descended testis.Testicular embryologyNormal testicular development begins at conception. The testis-determining factor is now identified as the SRY gene (sex-determining region on Y chromosome).The presence of this gene and an intact downstream pathway generally result in testicular formation.At 3-5 weeks' gestation, the gonadal ridge or indifferent gonad develops, and at 6 weeks, primordial germ cell migration occurs.Soon after, Sertoli cells develop and secrete müllerian-inhibiting substance (MIS), the level of which remains high throughout gestation and causes regression of müllerian ducts.At 9weeks, Leydig cells develop and secrete testosterone. Up to 28 weeks there is transabdominal movement to the internal inguinal ring. Transinguinal migration, thought to be under hormonal control, occurs from weeks 28-40, usually resulting in a scrotal testis by the end of a full term of gestation.OccurrenceSeen in 3% of full-term newborn boys, decreasing to 1% in boys aged 1 year. Spontaneous descent after the first year of life is uncommonPredisposing factors

.Prematurity- The prevalence rate is 30% n premature boys.

Low birth weight Twinning Maternal exposure to estrogen during the first

trimester. Siblings of boys with undescended testes A 7%

incidence rate is seen.EtiologyThe multifactorial mechanism of occurrence involves1) Differential body growth relative to spermatic cord/gubernaculums2) Increased abdominal pressure3) hormonal factors, including testosterone, MIS, and extrinsic estrogen4) development/maturation of the epididymis5) gubernacular attachment6) genitofemoral nerve/calcitonin gene–related peptide (CGRP).Clinical: The most useful classification is whether testes are palpable upon physical examination. -If nonpalpable, testes may be intra-abdominal or absent. -If palpable, testes may be undescended, ectopic, or retractile. Nonpalpable testes occur in approximately 20-30% of those who have cryptorchidism. The absent testis is thought to occur from an intrauterine or perinatal vascular event. Only 20-40% of nonpalpable testes are absent upon surgical exploration. Were abdominal 10%; inguinal 68%; prescrotal, 24%; ectopic/SIP, 11.5%; bilateral, 30%;

Imaging Studies: Abdominopelvic ultrasonography to determine the location of ectopic testis and rule out other associated abnormalities in the upper urinary tracts.Medical therapy: The appropriate time for treatment is when the individual is aged approximately 1 year. This age limit has decreased over the recent decades and is based on(1) the rarity of spontaneous descent after age 1 year and (2) the possible salvage of improved fertility by earlier

Associated anomalies/conditions may include the following: Patent processus vaginalis

Abnormal epididymis Cerebral palsy Mental retardation Wilms tumor Abdominal wall defects (eg, gastroschisis,

omphalocele, prune belly) Hypospadias Inguinal hernia Hemiscrotum Hydrocele Abnormalities of vas deferens and epididymis Klinefelter's syndrome Hypogonadotropic hypogonadism

Overall, 32-79% of undescended testes are reported to be associated with some type of epididymal abnormality. However, abnormalities that inhibit sperm transport (eg, complete caput separation, atresia, agenesis ) have been reported in only 8% of patients.History

Determination of whether the testis has ever been palpable in scrotum

History of prior inguinal surgery Prenatal history, ie, assisted reproductive

technique, maternal hormonal treatment, multiple gestations, prematurity

Family history, ie, cryptorchidism, hypospadias, intersex, precocious puberty, infertility, consanguinity

Physical examination Warm, relaxed patient Observation prior to examination Frog-leg position Milk down, palpating from iliac crest to scrotum

(soap or lubrication on fingertips may help) Scrotum, ie, hypoplastic, bifid, rugae,

transposition, pigmentation Contralateral testicular hypertrophy Ectopic sites, ie, superficial inguinal pouch or

transverse scrotal, femoral, prepenile, perineal, or contralateral hemiscrotum

Presence of hypospadias/chordee, normal stretched penile length

Serial examinations, if equivocalIndications for hormonal or surgical correction of cryptorchidism include the following: Possible improved fertility

Self-examination for testis mass (cancer) Correction of associated hernia Prevention of testicular torsion Avoidance of injury against pubic bone Psychological effects of empty scrotum

Lab Studies: For unilateral undescended testis without hypospadias, no lab studies are needed.For unilateral or bilateral undescended testes with hypospadias or bilateral nonpalpable testes, tests include the following:

Testing to rule out intersex condition (mandatory)

17-hydroxylase progesterone Testosterone Luteinizing hormone (LH) Follicle-stimulating hormone (FSH)

Complications of orchidopexy are as follows1.Inadequate testis position occurs in as many incomplete retroperitoneal dissection. 2.Testicular atrophy occurs in approximately 5% of cases due to devascularization. 3.Accidental division of the vas deferens occurs in 1-2% of patients.. 4.Epididymoorchitis is uncommon and may be treated