[Quiz]: Baby born with atypical genitalia, XY karyotype

June 15, 2017

A 3-month old baby born with atypical genitalia has an XY karyotype. The baby undergoes diagnostic laparoscopy. The baby is doing clinically well without medication.

Exhibit 1

 

 

 

A 3-month old baby born with atypical genitalia (Exhibit 1) has an XY karyotype.

 

 

Exhibit 2

 

 

The baby undergoes diagnostic laparoscopy. Exhibit 2 is an overview of the patient’s internal pelvic anatomy.

 

 

Exhibit 3

Exhibit 4

 

 

 

 

 

Exhibit 3 is a high-power image of the left gonad. Exhibit 4 is a high-power image of the right gonad. The baby is doing clinically well without medication.

 

 

 

 

 

Answers.

  • C. Streak

  • D. Ovotestis

  • D. Ovotesticular syndrome

Discussion

The diagnosis is ovotesticular syndrome, one of the rarest forms of disorders of sex development, characterized by the presence of both ovarian and testicular tissue.

The overview pelvic laparascopy image (Exhibit 2) shows retained Mullerian structures suggesting an absence of MIS production or function. The diagnosis is ultimately based on histologic analysis of what appears to be a homogeneous streak gonad on the patient’s left (Exhibit 3) and inhomogeneous streak on the right with an area of bulging gonadal tissue in the superior aspect of the laparoscopic image of the right gonad different from the classic streak appearance at the bottom aspect of the laparoscopic image (Exhibit 4). Histologically, the right gonad has both ovarian tissue and testicular tissue (the source of virilization in this XY baby).

Patients with XO karyotype (Turner’s syndrome) would have bilateral streak gonads (such as on the left, Exhibit 3) without the external genitalia virilization and the XY karyotype. Patients with Gonadal dysgenesis (Swyers’ syndrome) would have an XY karyotype but without the external genitalia virilization; ie, a female phenotype. The streak gonads in patients with gonadal dysgenesis are at risk for cancer and should be removed since they are non-functional in respect to both hormonal function and future germ cell function.

The external genitalia are not consistent with congenital adrenal hyperplasia (CAH). Note the open vaginal area inside of the expected common urogenital sinus (Exhibit 1). In addition, in CAH, you would expect normal ovaries internally, not streak gonads or an ovotestis.

Exogenous testosterone exposure from the mother to the fetus could cause the atypical genitalia phenotype, especially if this occurred later in gestation but again, you would expect normal ovaries.

In severe hypospadias, you would expect the gonads to look like testes, which is not the case.

The majority of patients with ovotestes syndrome have an XY karyotype but can also have an XX karyotype. The key to suspecting the diagnosis is the inhomogeneous streak on the right compared to the left and the need for an explanation of virilization. Fertility in XY patients with ovotesticular syndrome has not been reported. Patients with ovotesticular syndrome are often raised as females. Future gender identity is difficult to predict, however, and patients and families will need long-term medical support and counseling.

 

Laurence Baskin, MDDr. Baskin

 

 

Suggested reading

Fertility in disorders of sex development: A review. J Pediatr Urol 2016; 12:418-425.

Clinical review of 95 patients with 46, XX disorders of sex development based on the new Chicago classification. J Pediatr Adolesc Gynecol 2015; 28:6-11.

Surgery in disorders of sex development (DSD) with a gender issue: If (why), when, and how? J Pediatr Urol 2016;12:139-49.

To get weekly news from the leading news source for urologists, subscribe to the Urology Times eNews.