Cryptorchidism is defined as a failure of one or both testes to descend into the scrotum as the male fetus develops and is often discovered on routine newborh physical examination.
2-5% of full-term and 30% of premature male infants are born with an undescended testicle. It may affect one or both testes; 10 percent of cases are bilateral, and among unilateral cases there is a left-sided predominance
May be co-morbid with:
- congenital disorders of testosterone secretion or action (e.g. Kallmann syndrome)
- abdominal wall defects
- neural tube defects
- cerebral palsy
- various genetic syndromes (trisomy 18, trisomy 13, Noonan syndrome, Prader-Willi syndrome, Laurence-Moon-Biedl syndrome)
Passage through the inguinal canal begins in the 28th week of gestation.Failure to descend may be due to gonadotropin deficiency in utero, decreased Mullerian inhibiting factor, or increased estradiol in the placenta. Absent testes are due to agenesis or intrauterine vascular compromise (eg, torsion).
Differential Diagnosis of Cryptorchidism
- Retractile testis - usually can be diagnosed with careful history and physical
- Ectopic testis
- Agenesis - all testicular structures (eg, testis, testicular vessels, vas deferens) are absent
- Intrauterine torsion - remnants of the normal testicular architecture typically are present
- Congenital adrenal hyperplasia – look for salt-wasting syndrome
- Disorder of the androgen receptor
- True hermaphroditism
Important Historical Points
- Endocrine disturbance during pregnancy?
- Family history of unexplained neonatal deaths or genital anomalies?
- Abnormal pubertal development?
- Infertility issues?
- Were the testes were in a scrotal location in the neonatal period? (ie, before the cremasteric reflex becomes active)
- General: look for syndromic features
- Note the testicular position, consistency, and size in relation to the opposite testis
- Hypoplastic or poorly rugated scrotum or hemiscrotum
- Inguinal fullness
- Sweep hand from down the inguinal canal to gently express any retained testicular tissue into the scrotum. Hold the testis down for at least 1 minute. This fatigues the cremasteric muscle; when you let go, a retractile will remain in the scrotum whereas an ectopic testis immediately springs out of the scrotum.
- Bimanual digital rectal examination (under general anesthesia)
- Hypospadias + cryptorchidism: think intersex states
In infants, consider Karyotype, Electrolytes, LH, FSH, Testosterone, and Mullerian inhibiting factor. Also consider adrenal hormones and metabolites (such as 17-hydroxyprogesterone). In older children, it may be adequate just to check testosterone, LH, FSH, and MIS.
Imaging usually lacks sensitivity in detecting nonpalpable testis. Consider an ultrasound to look for gonads and to exclude the presence of a uterus. Also consider an ultrasound in obese boys, as the testes may be difficult to feel on exam.
Complications often minimized by prompt recognition and timely referral for treatment
- Testicular germ cell cancers
- NOTE: surgical correction of malposition (orchiopexy) reduces but does not eliminate the risk of having testicular cancer
- Related to the effect of testicular temperature on spermatogenesis
- Associated with lower sperm counts, sperm of poorer quality, and lower fertility rates
- Testicular torsion
- Seen predominantly in neonates and postpubertal boys
- Often occurs in association with the development of a testicular tumor (growing mass twists on itself)
- Inguinal hernia
- 90% of undescended testes are associated with patent processus vaginalis
- May present with an incarcerated or strangulated inguinal hernia
Timing is key!! Changes related to fertility occur in the undescended testicle as young as 1 year of age; thus orchiopexy is best performed before the changes occur, ideally as soon as possible after 6 months of age. Treatment can be hormonal, surgical, or both.
- Descent sometimes can be induced with hCG
- GnRH appears to be comparable to hCG in achieving testicular descent but is not approved for use in the US
- If testicle is palpable.
- The testicle is manipulated into the scrotum and sutured in place.
- The most significant complication of orchiopexy is testicular atrophy (rare).
- If testicle is non-palpable.
- May approach openly through groin or laparoscopically.
- This procedure determines whether or not the testis is present, positions and fixes viable testes within the scrotum; and removes nonviable testicular remnants.
- Barthold, JS, González, R. The epidemiology of congenital cryptorchidism, testicular ascent and orchiopexy. J Urol 2003; 170:2396.
- Hutson, John M., and Suzanne Hasthorpe. Testicular descent and cryptorchidism: the state of the art in 2004. Journal of pediatric surgery 40.2 (2005): 297-302.
- Kollin, Claude, et al. Growth of Spontaneously Descended and Surgically Treated Testes During Early Childhood. Pediatrics 131.4 (2013): e1174-e1180.
- Kokorowski, Paul J., et al. Variations in timing of surgery among boys who underwent orchidopexy for cryptorchidism. Pediatrics 126.3 (2010): e576-e582.
- Tasian, Gregory E., and Hillary L. Copp. Diagnostic performance of ultrasound in nonpalpable cryptorchidism: a systematic review and meta-analysis. Pediatrics 127.1 (2011): 119-128.
- Ferrer and McKenna Current Approach to the undescended testicle. Contemporary Pediatrics January 2000
- Elder Jack. Ultrasonaoraphy is Unnecessary in Evaluating Boys with a Nonpalpable Testis Pediatrics October 2002
- Cheng T. Undescended Testis Pediatrics in Review 2000 21:395
- Pettersson A. et al. Age at Surgery for Undescended Testis and Risk of Testicular Cancer. NEJM May 3, 2007