- 1 WHAT IS IT?
- 2 WHY IS IT A PROBLEM?
- 3 WHAT MAKES US SUSPECT IT?
- 4 HOW DO WE CONFIRM A DIAGNOSIS?
- 5 HOW DO WE RULE OTHER DIAGNOSES OUT?
- 6 HOW DO WE TREAT IT?
- 7 HOW WELL DO THE PATIENTS DO?
- 8 WAS THERE A WAY TO PREVENT IT?
- 9 WHAT ELSE ARE WE WORRIED ABOUT?
- 10 OTHER HY FACTS?
- 11 FURTHER READING
- 12 ARCHIVE OF STANDARDIZED EXAM QUESTIONS
WHAT IS IT?
Androgen Insensitivity Syndrome (AIS) is a condition caused by a defect in the androgen receptor (AR) in a chromosomal 46, XY male.
WHY IS IT A PROBLEM?
This defect in the AR leads to a loss of AR signaling, which in turn results in a normal appearing female phenotype (this is because androgen signaling is required for the development of many male characteristics). Patients develop external female genitalia but also will have the development of testes. These testicles will release mullein-inhibitin hormone that will inhibit the development of the upper vagina, cervix, uterus, and fallopian tubes.
WHAT MAKES US SUSPECT IT?
Gynecological exam can reveal the following findings:
- Female external genitalia
- Short vaginal canal
- Non-visible cervix (given no uterus in this condition)
- Scant pubic har
- Testes development can be present (often in labia majora)
- Absent uterus, and non-palpable ovaries.
Other exam findings:
- Breast development (can be Tanner stage 4)
- Axillary hair can be scant
HOW DO WE CONFIRM A DIAGNOSIS?
Serum analysis can reveal the presence of:
- Increased testosterone (lack of negative feedback, increased LH)
- Increased estrogen
- Increased LH (lack of negative feedback)
Ultrasound can confirm the absence of the uterus/fallopian tubes.
Genetic testing can identify the chromosomal/genetic causes for the AR deficiency
- Karyotype will reveal a 46 XY
HOW DO WE RULE OTHER DIAGNOSES OUT?
The increase in testosterone seen here in AIS differs from what is observed in other chromosomal abnormalities.
HOW DO WE TREAT IT?
Surgery can be used to remove the testicles that develop (often in labia majora). These testicles are at higher risk for developing malignancy.
HOW WELL DO THE PATIENTS DO?
Patients will be sterile for life
WAS THERE A WAY TO PREVENT IT?
WHAT ELSE ARE WE WORRIED ABOUT?
Malignancy is a risk in the testicles (if they are not removed surgically)
OTHER HY FACTS?
An example of male pseudohermaphroditism because the individual has testes (male) but female-appearing external genitalia.
ARCHIVE OF STANDARDIZED EXAM QUESTIONS
This archive compiles standardized exam questions that relate to this topic.
Page Updated: 03.03.2016