DESCRIPTION

• Incomplete or improper descent of one or both testicles; also called undescended testes (UDT) (1)
• Normally descent is in month 7 to 8 of gestation. The cryptorchid testis may be palpable or nonpalpable.
• Can be congenital or acquired
• Types of cryptorchidism
  • Prescrotal: at or above scrotal inlet
  • Abdominal: testis located inside the internal inguinal ring
  • Canalicular: testis located between the internal and external inguinal rings
  • Ectopic: located outside the normal path of testicular descent; may be ectopic to perineum, femoral canal, superficial inguinal pouch (most common), suprapubic area, or opposite hemiscrotum
  • Retractile: fully descended testis that moves freely between the scrotum and the groin
  • Iatrogenic: Previously descended testis becomes undescended due to scar tissue after inguinal surgery.
  • Also may be referred to as palpable versus nonpalpable (1)
• System(s) affected: reproductive
• Synonym(s): UDT

EPIDEMIOLOGY

ETIOLOGY AND PATHOPHYSIOLOGY

• Not fully understood, may involve alterations in
  • Mechanical factors (gubernaculum, length of vas deferens and testicular vessels, groin anatomy, epididymis, cremasteric muscles, and abdominal pressure), hormonal factors (gonadotropin, testosterone, dihydrotestosterone, and müllerian-inhibiting substance), and neural factors (ilioinguinal nerve and genitofemoral nerve)
  • Insulin-like growth factor 3 (IGF-3) or androgen receptor gene (1)
  • Environmental factors acting as endocrine disruptors
• Major regulators of testicular descent are the Leydig cell–derived hormones, testosterone, and IGF-3.
• Risk of ascent as high as 32% in retractile testis

RISK FACTORS

• Family history: highest risk if brother had UDT, followed by uncle and then father
• Low birth weight, prematurity, and small for gestational age (1)
• Retractile testes are at increased risk for ascent.
• Maternal smoking and diabetes during gestation

COMMONLY ASSOCIATED CONDITIONS

• Anatomic anomalies: inguinal hernia/hydrocele, abnormalities of vas deferens and epididymis, hypospadias, meningomyelocele
• Endocrine disorders: intersex abnormalities, hypogonadotropic hypogonadism, germinal cell aplasia
• Genetic disorders: Prune-belly syndrome, Prader-Willi syndrome, Kallmann syndrome, cystic fibrosis
• Wilms tumor

HISTORY

≥1 testicles in a site other than the scrotum

PHYSICAL EXAM

• Performed with warm hands, with child in sitting, standing, and squatting position
• A Valsalva maneuver and applied pressure to lower abdomen may help to identify the testes, especially a gliding testis.
• Failure to palpate a testis after repeated exams suggests an intra-abdominal or atrophic testis.
• An enlarged contralateral testis in the presence of a nonpalpable testis suggests testicular atrophy/absence.
• Testes should be palpated for quality and position at each recommended well-child visit (1)[B].

DIFFERENTIAL DIAGNOSIS

• Retractile testis (hypermobile testis): a normally descended testis that ascends into the inguinal canal because of an active cremasteric reflex (more common in males 4 to 6 years of age)
• Atrophic testis: may occur as a result of neonatal torsion
• Vanished testis may be the result of a lack of development or in utero torsion.

DIAGNOSTIC TESTS & INTERPRETATION

GENERAL MEASURES

• Rule out retractile testis.
• American Urological Association (AUA) guidelines on cryptorchidism do not recommend use of hormonal therapy to induce testicular descent due to low response rate and lack of evidence for long-term efficacy (1).

MEDICATION

Medical therapy is not indicated in the United States per the AUA guidelines on cryptorchidism in 2014 (1).

ISSUES FOR REFERRAL

• ≥1 testes not descended by 6 months age (1)[B]
• Bilateral nonpalpable UDTs (1)
• Newly diagnosed cryptorchidism after 6 months of age (1)[B]

SURGERY/OTHER PROCEDURES

• Benefits: avoids torsion, averts trauma, decreases but does not eliminate risk of malignancy, and prevents further alterations in spermatogenesis
• If no spontaneous testicular descent by 6 months of age (gestational age adjusted), surgery should be performed within 1 year (1)[B].
• Prepubertal orchidopexy decreases risk of testicular cancer (1).
• Laparoscopy/abdominal exploration is performed first if testis is nonpalpable.
• If palpable, an inguinal approach is usually performed. If low-lying, a single-incision scrotal approach can also be considered but may increase the risk of hernia.

FOLLOW-UP RECOMMENDATIONS

• Initial follow-up within 1 month of surgery and periodically thereafter to assess testicular size/growth
• Patients with retractile testes should be examined at least annually to monitor for secondary ascent until testis is no longer retractile (1)[B].

DIET

No restrictions

PATIENT EDUCATION

Discuss with parents about causes, treatments, patient’s reproductive potential, and increased risk for testicular cancer.

PROGNOSIS

• Disorder is usually corrected with surgical therapy; however, there are possible lifelong consequences.
• If testicle is absent or orchiectomy is required, may consider placement of testicular prosthesis.
• Early orchidopexy may decrease risk of testicular damage and risk of malignancy.

COMPLICATIONS

• Paternity rates are similar to the general population for men with a unilateral UDT; however, lower (33–65%) for men with bilateral UDT
• Abnormalities also have been identified in the contralateral descended testis, suggesting that unilateral cryptorchidism is a bilateral disease.

ICD10

• Q53.9 Undescended testicle, unspecified
• Q53.20 Undescended testicle, unspecified, bilateral
• Q53.10 Unspecified undescended testicle, unilateral
• Q53.11 Abdominal testis, unilateral
• Q53.21 Abdominal testis, bilateral
• Q53.22 Ectopic perineal testis, bilateral
• Q53.12 Ectopic perineal testis, unilateral

SNOMED

• 204878001 Undescended testicle (disorder)
• 268228006 Undescended testes - bilateral
• 431781000124107 Bilateral intra-abdominal testes (disorder)
• 438401000124104 Palpable undescended testicle (disorder)