Differential Diagnosis
The patient presents with primary amenorrhea, which is the absence of menstruation in a person who has reached the age of 16 years. The following differential diagnoses are considered:
- Single most likely diagnosis
- Androgen Insensitivity Syndrome (AIS): This diagnosis is likely due to the patient's presentation of primary amenorrhea, normal breast development, and absence of uterus, cervix, and ovaries on pelvic ultrasonography. The elevated testosterone level (400 ng/dL) also supports this diagnosis, as individuals with AIS have a normal male karyotype (46,XY) and produce testosterone, but their bodies are unable to respond to it due to a mutation in the androgen receptor gene.
- Other Likely diagnoses
- Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome: This condition is characterized by the congenital absence of the vagina, cervix, and uterus, which is consistent with the patient's pelvic ultrasonography results. However, individuals with MRKH syndrome typically have normal ovarian function and do not have elevated testosterone levels.
- Gonadal dysgenesis: This condition involves abnormal development of the gonads, which can lead to primary amenorrhea. The patient's elevated testosterone level and absence of uterus, cervix, and ovaries on pelvic ultrasonography could be consistent with this diagnosis.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Adrenal tumor or cancer: Although rare, an adrenal tumor or cancer could produce excessive androgens, leading to elevated testosterone levels. It is essential to rule out this possibility to avoid missing a potentially life-threatening condition.
- Ovarian tumor or cancer: Similarly, an ovarian tumor or cancer could produce excessive androgens, leading to elevated testosterone levels. Although the pelvic ultrasonography did not show any ovaries, it is crucial to consider this possibility to avoid missing a potentially life-threatening condition.
- Rare diagnoses
- 5-alpha-reductase deficiency: This is a rare genetic disorder that affects the production of dihydrotestosterone (DHT), leading to undervirilization in individuals with a 46,XY karyotype. The patient's presentation of primary amenorrhea and elevated testosterone level could be consistent with this diagnosis, although it is rare.
- Denys-Drash syndrome: This is a rare genetic disorder characterized by congenital nephropathy, genital abnormalities, and an increased risk of Wilms tumor. The patient's presentation of primary amenorrhea and absence of uterus, cervix, and ovaries on pelvic ultrasonography could be consistent with this diagnosis, although it is rare.