Address correspondence to: Werther Adrian Clavelli, MD, Vanderbilt University, De­partment of Radiology, 21^st and Garland, Nashville, TN 37232-5316, Ph: 615-343-0595, Fax: 615-343-4890

Synonyms: Undescended testis.

Definition: The testis is arrested in the normal path of descent between the renal and scrotal areas. It remains in the pelvic cavity or in the inguinal canal until puberty, when it descends or remains indefinitely in the abnormal position^1,4.

Etymology: kruptoV = hidden; ­orciV = testis.

Prevalence: 34:10,000 (fig. 2).

Etiology: Unknown.

Pathogenesis: Unclear. All the theories suggest an abnormal hormonal stimulation or reception.

Associated anomalies: See table 1. Central nervous system: meningomyelocele, hydrocephalus, an­encephaly, midline neurofacial defects; Kallman"s syndrome; urinary tract: rotation abnormalities of the kidney, horseshoe kidney, Wilms" tumor; genital tract: hypospadias, inter-sexuality^1,2.

Differential diagnosis: ectopic testicle, physiologic cryptorchidism.

Prognosis: Infertility when the treatment is delayed, neoplasm. Possible complication: torsion, hernia^3,7.

Recurrence risk: An autosomal-dominant or Y-linked inheritance has been proposed. It has been confirmed in 1.5 to 4.0% of fathers and 6% of brothers¹¹ of affected children.

Management: Standard obstetrical care.

Treatment: Surgical correction (orchi­pexy and hernioplasty) around one year. Hormonal therapy: hCG or GnRH^1,2,3.

MESH Cryptorchidism ICD9 752.5 CDC 752.501

Introduction

Although cryptorchidism is one of the most common congenital abnormalities of the male genitourinary tract , we are not aware of the prenatal diagnosis of this condition. In the case of the non-palpable testis, a prenatal diagnosis can help the pediatrician by ascertaining the existence and position of the testis. We describe the case of a 16-year-old primigravida referred to Vanderbilt University Medical Center for a Level II ultrasound because of an outside examination demonstrating several anomalies.

Case report

A 16-year-old primigravida was referred at 31 weeks because an outside examination demonstrated polyhydramnios, a questionable neural tube defect and an abnormal 4-chamber view. Our examination confirmed the polyhydramnios and demonstrated a spina bifida with scoliosis. Other findings included bilateral clubfeet, microcephally and an undescended testicle in the left inguinal canal (fig. 1). Amniocentesis revealed a normal 46 XY karyotype. At 32 weeks the mother had premature contractions with a fully dilated cervix, and an emergency cesarean section was performed. Apgar scores were 3 and 8 (1 and 5 minutes, respectively).

Figure 1: The ectopic testicle is visible under the abdominal subcutaneous tissues.

At physical examination, the premature infant had a dismorphic appearance, with an open lumbar spinal defect, hyper­te­lo­rism, small low-set ears, micrognathia, excess nuchal skin folds and non-palpable testes. The cardiovascular examination was normal. The newborn presented signs of contractures of the hips and knees, and had bilateral simian creases and equinovarus. The neuro­logical exam revealed spontaneous movement of all extremities, which were held rigidly. An echocardiogram showed a large truncus arteriosus overriding a membranous ventriculoseptal defect, and there was no evidence of congestive heart failure on the exam. Neurosurgery to close the myelomeningocele was performed five days after birth. Because it was felt that the cardiac lesion could not be operated on with the coexistent neurological defect, the patient was treated symptomatologically until he died 10 days after birth.

Discussion

The fact that a minor anomaly such as an undescended testicle was diagnosed, but a severe—and ultimately fatal one—such as truncus was missed, illustrates some of the inconsistencies of prenatal diagnosis.

One of the most common problems in pediatric urology is the non-palpable testicle, including the ectopic and the true undescended testicle.

Prevalence

The prevalence is 340:10,000 at birth, but half of them descend during the first month^1-3 (fig. 2). 

Figure 2: Prevalence of cryptorchidism at various ages13. Preterm and full-term infants are separated in weight (grams) categories. 

Definition

The word cryptorchidism means hidden testicle. It includes the true undescended, ectopic and absent testicles.

The true undescended testicle may be intra-abdominal, inguinal or suprascrotal.

Ectopic testicles migrate outside the external inguinal ring to an abnormal position, (fig. 3) such as the superficial ring pouch (most commonly), perineum, prepenile region, etc.

An absent testicle occurs only in 20 to 40% and can be present as a unilateral or bilateral anomaly^1,2,3.

Figure 3: Localization of the true undescended testicles and the ectopic testicles

Pathogenesis

The testicle and epididymis need to be about 1 or 2° C cooler than the rest of the body. The mechanism responsible for the descent of the testicle remains unclear. Three theories have been suggested: absence or anomalies of the gobernaculum testis, congenital gonadal defect and deficient gonadotrophin hormonal stimulation¹.

Absence or anomalies of the gobernaculum testis

Some authors hypothesize that the descent of the testicle is due to traction by the gobernaculum and/or cremaster muscle. Since the gobernaculum testis is androgen-responsive, the pathology may be due to the hormonal stimulation or to a defect of the gobernaculum and/or cremaster muscle.

Congenital gonadal defect

In this theory the testis is insensitive to gonadotrophins. This theory explains unilateral cryptorchidism when only one testis is non-responsive to hormonal stimulation.

Deficient gonadotrophin hormonal stimulation   

Maternal or chorionic hormones must stimulate androgen production in the last month of the gestation. If this stimulation does not occur, bilateral cryptorchidism may result. This theory also explains the difference in incidence between preterm and term infants^1,3 .

Associated anomalies

Associated anomalies are listed in Table 1. 

Table 1: Syndromes associated with cryptorchidism^14-16.

Central nervous system

Any disorder that involves the hypothalamic-pituitary-testicles axis could be associated with cryptorchidism. These include: anencephaly with an undeveloped pituitary, pituitary aplasia and spina bifida; and Kallman"s syndrome (hypogonadotrophic hypogonadism and anosmia)^1,2,3.

Urinary tract

Three to 17% have associated urinary anomalies including malrotation, horseshoe kidney, hypospadias and renal agenesis^8,9. Fetuses with Wilms" tumor have a higher incidence of bilateral cryptorchidism when compared to the general population (278:10,000 versus 0,078:10,000)^2,10.

Localization

Localization of the true undescended testicle and the ectopic testicle is demonstrated in fig. 3.

Differential diagnosis

Retractile testicle or physiologic cryptorchidism are not truly undescended testis. They are in an extra-scrotal position because the cremaster muscle retracted them out of the scrotum in some specific situations (cold, physical activity, excitment)¹.

Prognosis

Infertility

The histological degradation in the seminiferous tubules is proportional to the duration of the dystopia and the distance from the scrotum^3,6.

Neoplasia

Undescended testes are reported to be 35-48 times more likely to undergo malignant degeneration than the normal testis. Seminoma and embryonal cell carcinoma are the two most frequent^1,7.

Other complications

Two other possible complications are torsion and herniation^2,3,7.

Recurrence risk

An autosomal-dominant or Y-linked inheritance has been suggested¹¹. One study confirmed undescended testicle in 1.5 to 4.0% of fathers and 6% of brothers of affected patients (higher in bilateral cryptorchidism). Heritability in first degree male relatives is estimated to be 0.67, plus or minus 0.16¹². 

Management

Standard obstetrical care.

Treatment

Patients are managed expectantly up to the age of one year. Hormonal therapy may be tried during this period, using either human chorionic gonadotrophin (hCG) or gonadotrophin-releasing hormone (GnRH). If the condition persists after one year, surgical correction with orchipexy and hernio­plasty is advised in order to prevent potential complications related to infertility^1-3.

References

1. McAninch JW. Disorders of the testis, scrotum and spermatic cord. In: Tanagho EA, McAninch JW. Smith"s General Urology. Appleton & Lange, Norwalk, 13th edition, 1992, pp. 616-620.

2. Koogan, S. Cryptorchidism. In: Kelalis PP, King LR, Belman AB.Clinical Pediatric Urology. W. B. Saunders, Harcourt, 3rd edition, 1992, pp. 1050-1083.

3. Rajfer J. Congenital Anomalies of the testis. In: Walsk DC, Retick AB, Saney TA, et al. Campbell"s Urology. W. B. Saunders, Harcourt, 6th edition, 1992, pp. 1543-1562.

4. Bartone FF, Schmidt MA: Cryptorchidism: incidence of chromosomal anomalies in 50 cases. J Urol 127:1105,1982.

5. Radhakrishnan J, Morikawa Y, Donohoe PK, et al: Observations on the gubernaculum testis. Invest Urol 16:365, 1979.

6. Ludwig G, Potenpe J.Der optimale zeipunkt der baliandlung des krytorchismus. Dtsh Med Wochen. 100:680,1975.

7. Pike MC, Chilvers C, Peckham Mj: Effect of age at orchidopexy on risk of testicular cancer. Lancet 1:1246,1986.

8. Kleintech B, Hadziselimovic F, Hesse V, et al: Kongenitale hodendystopien. Stuttgart, Georg Thieme, 1979.

9. Bishop MC, Whitaken, RH. Associated renal anomalies in familial cryptorquidism (letter). Lancet 2:249. 1979.

10. Breslow N, Beckwith JB: Epidemiological features of Wilms" tumor study. J Natl Cancer Inst. 68:429, 1982.

11. Pardo-Mindan FJ, Vargas T, Garcia JF, et al.: Familial cryptorchidism (letter). Pediatrics 56: 616,1975.

12. Czeizel A, Erodi E, Toth J. Genetics of undescended testis. J Urol 126:528-529,1981.

13. Scorer GC. Farrington GH: Congenital Deformities of the Testis and Epididymis. London, Butterworths, 1971.

14. Geffner ME, Lippe BM: Genetic and endocrinologic syndromes associated with cryptorchidism. in The undescended testis. Ed. EW Fonkalsrud, W. Mendel. Chicago, Year Book Medical Publisher, 1981

15. Rajfer J, Walsh PC: Testicular descent. Birth Defects 13: 107, 1977

16. Hadziselimovic F: Cryptorchidism. Management and implications. New York, Springer-Verlag, 1983.