CRYPTORCHIDISM

Alternate Names: Undescended testicles

Overview: Cryptorchidism literally means hidden or obscure testis and generally refers to an undescended or maldescended testis. Untreated cryptorchidism clearly has deleterious effects on the testis over time. 

Phenotype/Characteristics: Testicles absent from the normal scrotal position can be:

1. from high the posterior (retroperitoneal) abdomen, just below the kidney, to the inguinal ring;

2. in the inguinal canal;

3. ectopic, usually outside the inguinal canal and sometimes even under the skin of the thigh, the perineum, the opposite scrotum, or the femoral canal;

4. found to be undeveloped (hypoplastic) or severely abnormal (dysgenetic);

5. found to have vanished (anorchia)

The condition is associated with reduced fertility, increased risk of testicular tumors, and psychological problems. It also predisposes the patient to testicular torsion and inguinal hernias.

Frequency: About 3% of full-term and 30% of premature infant boys are born with at least one undescended testis. However, about 80% of cryptorchid testes descend by the first year of life (the majority within three months), making the true incidence of cryptorchidism around 1% overall.

Cryptorchidism is identified in 1.5-4% of fathers and 6.2% of brothers of patients with cryptorchidism. Heritability in first-degree male relatives is estimated to be 0.67.

Diagnosis: An examination confirms that one or both of the testicles are not in the scrotum.

The health care provider may or may not be able to feel the undescended testicle in the abdominal wall above the scrotum. Approximately 20-30% of patients with cryptorchidism have nonpalpable testes. Nonpalpable testes may be intra-abdominal or absent. Palpable testes may be undescended, ectopic, or retractile.

Causes: Cryptorchidism is multifactorial. Extensive research and clinical observations have elucidated some of the factors involved, but the exact mechanism of cryptorchidism has proven to be elusive.

Low birth weight often results in the condition.

Transabdominal descent of the testis involves differential growth of vertebrae and pelvis and is facilitated by the development of the gubernaculum, processus vaginalis, spermatic vessels, and scrotum. A normal hypothalamic-pituitary-gonadal axis is a prerequisite for testicular descent. Furthermore, testosterone and its conversion to dihydrotestosterone (DHT) are also necessary for continued migration, especially during the inguinoscrotal phase.

Although its exact mechanism of action is unclear, the gubernaculum has significant importance in undescended testes. In patients with cryptorchidism, the gubernaculum is not firmly attached to the scrotum, and the testis is not pulled into the scrotum. 

Intra-abdominal pressure also appears to play a role in testicular descent. Conditions associated with decreased pressure include prune belly syndrome,cloacal exstrophy, omphalocele, and gastroschisis, among other various syndromes. Each is associated with an increased risk of undescended testes.

Associated anomalies: Associated anomalies and conditions may include the following:

•      Patent processus vaginalis
•      Abnormal epididymis
•      Cerebral palsy
•      Mental retardation
•      Wilms tumor
•      Abdominal wall defects (eg, gastroschisis, omphalocele, prune belly syndrome)
•      Hypospadias

Treatment/Recommendations/Therapies: Most cases get better on their own, without any treatment. Medicine or surgery to correct the condition is usually successful.

Cryptorchidism should be treated when the patient is aged approximately 6 months. 

Human chorionic gonadtropin (hCG) is administered via intramuscular injection and stimulate androgen production and testicular descent (mechanism still unknown). Ginadtropin releasing hormone promoted the same effect and may be used for a combined hormonal treatment.

Successful surgical placement of the testis in the scrotum (adequate mobilization of the testis and spermatic vessels, ligation of the associated hernia sac, and adequate fixation of the testis in a dependent portion of the scrotum) can be employed.

Support Groups:

I Have Cryptorchidism

http://www.experienceproject.com/groups/Have-Cryptorchidism/97567

References:

Kaneshiro, N. (2012) Undescended testicle. ADAM Medical Encyclopedia. Retrieved March 12, 2013 from the URL: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001968/

Sumfest, J. (2012). Cryptorchidism. Medscape reference. Retrieved March 12, 2013 from the URL: http://emedicine.medscape.com/article/438378-overview

Photo from:
http://wikis.lib.ncsu.edu/images/f/f6/Cryptorchidism.jpg