Teaching Case

A one-month old child presented with atypical genitalia. On examination, an enlarged phallus and a small scrotal sac with skin rugosities was seen (Figure 1). Both scrotal sacs were empty, however a small gonad was palpable in the right inguinal region. Penoscrotal hypospadias with a single meatus was noted.

MRI Pelvis showed a uterine-like structure posterior to the urinary bladder, and bilateral oval homogeneous structures in both inguinal canals suggestive of dysgenetic testes. A possible small prostate was noted at its expected location (Figure 2).
Ultrasound showed a uterus measuring 22x8x7mm located behind the urinary bladder, a normal appearing cervix, and part of the vagina could also be seen. A faint central endometrial lining could be appreciated in the uterus (Figure 3). Both scrota were empty. Both gonads were located in the inguinal canal (Figure 4). The right gonad measured 13x5mm, the left 10x6mm. No ovarian follicular tissue was seen in either inguinal canal or pelvis.
Ultrasound of the upper abdomen to exclude any adrenal lesion showed no abnormality.
Imaging diagnosis of an infantile uterus and bilateral dysgenetic undescended testes located in the inguinal canals was made.

The disorders of sexual development (DSD) are a group of conditions resulting from mismatch between chromosomal, gonadal and anatomic sex[1, 2]

Our patient presented with atypical genitalia and a right sided palpable gonad, which is considered to be a testes unless proven otherwise. Enlarged phallus and formation of scrotal sacs with rugosity suggest androgen exposure in utero.

Imaging helps establish the presence or absence of the uterus or other Mullerian structures and is diagnostically helpful. As well as producing androgens, testes produce anti-Mullerian hormone (AMH) which is responsible for regression of Mullerian structures in males. The presence of a uterine-like Mullerian structure in a patient with ambiguous genitalia, and an XX karyotype, may be secondary to CAH (congenital adrenal hyperplasia) and associated excess androgen exposure, or may occur in patients with an XY karyotype but with defective AMH production preventing the inhibition of the development of Mullerian structures. Persistent Mullerian duct syndrome (PMDS) is a rare condition with presence of a uterus in a phenotypic male due to defective AMH production or action. The penis is normally developed but cryptorchidism may be present.
In addition to being diagnostically helpful, the presence of a uterus also indicates possibility of having menstruation and pregnancy using artificial reproduction techniques for such children. This is an important factor when considering the sex of rearing.

In the index case, hormonal profile showed FSH of 9.75 IU/L, LH 9.55 IU/L and serum total testosterone 148 ng/dL(N 20-130 ng/dL) and AMH of 16.56ng/ml. The karyotype result was 45, X/46, XY. Presence of well-formed phallus and scrotum, production of testosterone (therefore its impact on androgenization of brain) favoured male sex of rearing in this child. This would entail orchidopexy (or orchidectomy if gonad is a streak or cannot be brought down to scrotal sac), multi-stage hypospadias repair and chordee correction. The risk of gonadal malignancy in individuals with 45, X/46, XY mosaicism and its variants has been described to be 10–15% [3], however, it can be as high as 50% [4], in those with most pronounced sexual ambiguity. Hence retained gonads need to be periodically clinically and radiologically evaluated for development of malignancy. Other associations include short stature, Turner syndrome like dysmorphic features and renal and cardiac malformations.

Imaging is the key to establishing an accurate diagnosis and guiding management. Ultrasound is diagnostic and MRI may be performed in select cases.

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