Clinical Diagnosis for Primary Amenorrhoea

This case involves a 16-year-old female presenting with primary amenorrhoea (never having had a menstrual period). Key findings include:

• Normal secondary sexual characteristics (indicating adequate oestrogen production).
• Normal female karyotype ($46,XX$).
• Normal ovaries and fallopian tubes on ultrasound.
• Absent uterus on ultrasound.

Evaluating Differential Diagnoses

We can exclude several conditions based on the provided information:

• Androgen Insensitivity Syndrome (AIS): This condition typically occurs in individuals with a $46,XY$ karyotype. The patient's $46,XX$ karyotype rules out AIS.
• Turner Syndrome: Patients with Turner syndrome usually have a $45,X$ karyotype and often present with underdeveloped secondary sexual characteristics and gonadal dysgenesis. This patient has normal secondary sexual characters and a $46,XX$ karyotype.
• Primary Ovarian Failure: This would involve non-functioning ovaries, leading to lack of oestrogen and failure to develop secondary sexual characteristics. The patient has normal secondary sexual characters and normal-appearing ovaries on ultrasound, making this diagnosis unlikely.

Identifying Mayer-Rokitansky-Küster-Hauser Syndrome

Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a congenital condition characterized by the absence or underdevelopment of the uterus and vagina in females with a normal karyotype ($46,XX$), normal ovaries, and normal development of secondary sexual characteristics. The patient's presentation aligns perfectly with the diagnostic criteria for MRKH syndrome.