A 14-year-old girl has not started menstruation. She has normal breast development (Tanner IV), normal pubic hair, but no menstruation and is found to have a blind vaginal pouch. Karyotype is 46,XY. What is the likely diagnosis?

• A Complete androgen insensitivity syndrome (CAIS) ✓
• B Turner syndrome
• C Kallmann syndrome
• D Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome

Explanation

Complete androgen insensitivity syndrome (CAIS) presents as primary amenorrhoea in a phenotypic female with 46,XY karyotype, normal breast development (from peripheral aromatisation of androgens to oestrogen), absent or sparse pubic/axillary hair (loss of androgen effect), and a blind vaginal pouch with no uterus. Undescended testes are present in the inguinal canal or abdomen with malignant potential (gonadoblastoma risk ~2–3% in adulthood). Gonadectomy after puberty completion (to allow natural feminisation) is recommended. MRKH has 46,XX with absent uterus/upper vagina but normal ovaries and hair. Kallmann has anosmia and lack of puberty. Turner presents with streak gonads and 45,X.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.