Differential Diagnosis for the Newborn
- Single most likely diagnosis
- Cryptorchidism: This is the most likely diagnosis given the absence of a palpable testicle in the right hemiscrotum and the hypoplastic, poorly rugated appearance of the right scrotum. Cryptorchidism, or undescended testes, is a common condition in preterm males, occurring in up to 30% of those born before 34 weeks of gestation.
- Other Likely diagnoses
- Ectopic testis: Although less common than cryptorchidism, an ectopic testis, where the testicle is located outside the normal path of descent, is a possibility. However, the absence of a mass in the inguinal canal makes this less likely.
- Testicular regression syndrome: This condition involves the loss of a testis during fetal development, which could explain the absence of a palpable testicle. However, it is less common than cryptorchidism.
- Do Not Miss diagnoses
- Testicular torsion: Although rare in newborns, testicular torsion is an emergency that requires prompt surgical intervention to save the testicle. The absence of a palpable testicle and a hypoplastic scrotum could potentially be signs of torsion, especially if the newborn shows signs of distress or if the condition is not recognized promptly.
- Inguinal hernia: While the examination did not reveal a mass in the inguinal canal, an inguinal hernia could potentially contain the undescended testicle, and its diagnosis is crucial for management.
- Rare diagnoses
- Persistent Müllerian duct syndrome: A rare condition where Müllerian duct structures (such as the uterus and fallopian tubes) persist in males, often associated with cryptorchidism. This would be an unusual finding but could be considered in the context of other genital anomalies.
- Gonadal dysgenesis: Conditions affecting the development of the gonads, which could result in abnormal testicular development or location. These are rare and often associated with other genetic or chromosomal abnormalities.