Case

An 8 month old male is brought to you for a second opinion. The child was found to have only one teste palpable at birth and it still is not present in the scrotum. The infant is otherwise doing well. How would you advise the parents on the further care of this child?

Cryptorchidism is defined as the absence of one or both testes in the scrotum after one year of age. 

1. There is an incidence of 1/125 births. 
2. The incidence is increased in preterm males because the normal descent of the testis into the scrotum doesn't occur before 7 months of gestation. 
3. 30% are bilateral. 
4. The right side has a higher incidence than the left. 
5. There is a 2-3% incidence of atrophy or absence. 
6. There is an association with other congenital anomalies and chromosomal defects. 
7. There is an increased incidence if other family members have had undescended testes.
8. Almost 100% are associated with inguinal hernias.
9. The testes can be found along the route of normal descent with 10% intra-abdominally, 40% in the inguinal canal, 25% at the prescrotal area, and 25% ectopic.

1. A Hernia is always associated with undescended testis and is common with an ectopic testes
2. Torsion of the teste and incarceration of the hernia
3. Malignancy- there is a 20 fold increase of malignancy in the undescended teste and the further away from the scrotum, the greater the incidence. Seminomas are the most common cancers and early repair may be associated with a decreased incidence of malignancy. Most studies have shown that repairing the undescended teste does not decrease the incidence of malignancy but these were done on boys who had their repair at a later time. At the least, the placement of the teste in the scrotum allows for easier self examination and earlier detection.
4. Infertility- The longer the teste is out of the scrotum, the greater the incidence of infertility. There is questionably an increased infertility in unilateral cryptorchidism and almost 100% of men with unrepaired bilateral cryptorchidism will be infertile. 2/3 of bilateral cryptorchidism repaired later in childhood will be infertile. Histologic changes include loss of germ cells, Leydig cells, and increased fibrosis. Most of the follow-up studies on fertility were done on boys who had orchiopexy at later ages than presently recommended. 
5. Psychological

1. Physical examination will diagnose cryptorchidism. It is most commonly misdiagnosed because the infant has retractile testes secondary to a hyperactive cremasteric reflex. Must have a warm environment to examine properly and parents can often find both teste in the bath. As the child gets older, the cremasteric reflex causes less retraction because the teste gets heavier.
2. Ultrasound may be helpful 
3. FSH and LH levels that are increased may indicate absence of testicular tissue. Poor testosterone response to hCG may also aid in diagnosing the absence of functional testicular tissue.

1. hCG- may be successful with bilateral cryptorchidism, especially if the testes are near the scrotum. Don't use if unilateral
2. Surgery- best performed near the end of the first year of life. Locate the testes and bring into the scrotum (orchiopexy) or remove atrophic tissue. May consider testicular prostheses. Must also fix the indirect inguinal hernia. 

1. Rabinowitz, Ronald and Hulbert,William. Cryptorchidism. Pediatrics in Review July 1994.
2. Ferrer and McKenna Current Approach to the undescended testicle.  Contemporary Pediatrics January 2000
3. Elder Jack. Ultrasonaoraphy is Unnecessary in Evaluating Boys with a Nonpalpable Testis Pediatrics October 2002
4. Cheng T. Undescended Testis Pediatrics in Review 2000 21:395
   
5. Pettersson A. et al. Age at Surgery for Undescended Testis and Risk of Testicular Cancer.  NEJM May 3, 2007