137: Surgical Diseases of the Newborn: Urologic Disorders

INTRODUCTION

Renal masses are discussed in Chapter 136.

UNDESCENDED TESTIS (CRYPTORCHIDISM)

I. DEFINITION

Testicular descent can occur prior to birth or in the first 6 months of life, after which cryptorchidism or undescended testis occurs in up to 10% of premature infants and 0.8% of term infants.

II. CLINICAL PRESENTATION

Testicles may be nonpalpable or located along the course of the inguinal canal, in the superior scrotum, retroscrotally, and in the perineum. The ipsilateral scrotum may be hypoplastic, and a hernia or hydrocele may also be present. Cryptorchidism may be associated with other anomalies such as disorders of sexual development (especially in the presence of hypospadias), prune-belly syndrome, bladder exstrophy, pituitary disorders, and multiple other syndromes.

III. DIAGNOSIS

Careful examination with a warm hand sweeping lateral to medial from the anterior superior iliac spine to the ipsilateral groin is the most effective method of distinguishing a palpable from a nonpalpable testis.

1. Palpable testes. A palpable testis must be distinguished from hernia, hydrocele, nubbin, and a long, looping portion of vas or epididymis. Infants with a palpable undescended testis should be followed to ensure proper descent by 6 months of age.

2. Nonpalpable testes. Imaging studies are not indicated to help identify nonpalpable testes. If testicles are nonpalpable at 3 months of age, referral to a pediatric urologist is needed. If both testes are nonpalpable, a disorder of sexual differentiation, including congenital adrenal hyperplasia in a genetic female, should be considered. The incidence of disorders of sexual differentiation in patients with hypospadias and bilateral nonpalpable testis is high and warrants a karyotype evaluation.

IV. MANAGEMENT

Spontaneous descent is possible until 6 months of age, after which there is only a 1% likelihood of spontaneous decent. After 6 months of age, orchiopexy is indicated for malpositioned palpable testicles. For nonpalpable testes, laparoscopy is indicated to localize the testis or identify the characteristic blind-ending spermatic artery and vas deferens entering the internal ring.

SCROTAL AND TESTICULAR MASSES

I. DEFINITION

The differential diagnosis of an abnormal testicular examination in an infant includes the following:

1. Hydrocele. Fluid within the tunica vaginalis and/or along the spermatic cord. Hydroceles may have continuity with the peritoneal cavity via a patent processus vaginalis (communicating hydrocele), or be confined to the tunica vaginalis and spermatic cord distal to an obliterated processus vaginalis (noncommunicating hydrocele).

2. Hernia (most commonly indirect inguinal). Protrusion of intra-abdominal contents through a patent processus vaginalis lateral to the epigastric vessels along the spermatic cord.

3. Testicular torsion. Twisting of the spermatic cord with reduction or cessation of testicular blood flow.

4. Testicular tumor. Rare in newborns.

II. CLINICAL PRESENTATION