In a 3‑year‑old boy with unilateral undescended testis and absent scrotum on that side, which disorder of sexual development is most commonly associated?

Associated Conditions with Unilateral Undescended Testis and Absent Scrotum

The correct answer is A (Hypospadias) and B (Inguinal hernia), but if forced to choose the single condition most directly related to sexual development, hypospadias is the answer, as it indicates potential disorders of sex development or aberrant androgen signaling.

Primary Associated Conditions

Inguinal Hernia (Most Common Structural Association)

• Inguinal hernia is explicitly identified by the American Urological Association as one of the main reasons for treatment of cryptorchidism, alongside fertility concerns, malignancy risk, and torsion 1
• This is the most common associated structural anomaly with undescended testis and represents a direct treatment indication 1, 2
• Any boy with cryptorchidism should be examined for inguinal bulge or hernia during physical examination 1

Hypospadias (Sexual Development Indicator)

• The presence of cryptorchidism with phallic anomalies such as hypospadias should prompt consideration of disorders of sex development 1
• Hypospadias and inguinal hernias are documented as the most common associated anomalies with undescended testis 2
• Acquired cryptorchidism is more common in boys with proximal hypospadias, suggesting aberrant androgen signaling may predispose to both anomalies 1
• Hypospadias indicates potential aberrant androgen signaling or disorders of sex development requiring additional evaluation 1

Clinical Reasoning for This Case

Why Hypospadias is the Sexual Development Answer

• In a 3-year-old with unilateral undescended testis AND absent scrotum on that side, this presentation suggests more than simple cryptorchidism 1
• The absent scrotum indicates potential incomplete masculinization or aberrant androgen signaling during development 1
• This combination (cryptorchidism + phallic/scrotal anomalies) specifically warrants evaluation for disorders of sex development 1

Why Inguinal Hernia is Also Correct (But Not Sexual Development-Related)

• While inguinal hernia is the most common structural association, it does not indicate aberrant sexual development 1, 2
• It represents a mechanical/anatomical association rather than an endocrine or sexual differentiation issue 1

Conditions NOT Associated

Pyloric Stenosis (Option C)

• No evidence links cryptorchidism with pyloric stenosis 3, 1
• This is an unrelated gastrointestinal condition with different embryologic origins

Congenital Heart Disease (Option D)

• There is no evidence linking isolated cryptorchidism with congenital heart defects according to American Urological Association guidelines 1

Critical Clinical Pitfall

When you see cryptorchidism combined with other genital anomalies (absent scrotum, hypospadias, micropenis), you must consider disorders of sex development 1. This is particularly urgent if bilateral and nonpalpable, as it could represent life-threatening congenital adrenal hyperplasia in a genetic female (46,XX) 3.