SAT-213 Late Diagnosis of Complete Androgen Insensitivity

BACKGROUND: Complete androgen insensitivity (CAIS) is a rare cause of primary amenorrhea and is usually diagnosed in menarche. Patients with CAIS are phenotypically female with a 46, XY karyotype, have elevated testosterone, LH, and FSH levels, and have little or no virilization due to androgen receptor gene mutations. The recommended treatment is orchiectomy due to the increased risk of gonadal malignancy and post-operative hormonal therapy. CLINICAL CASE: A 31-year-old female with no past medical history presented for evaluation of primary amenorrhea. She was born full term with a normal IQ, and no developmental delays or disabilities. The patient had no menstrual periods, minimal breast development, and sparse facial, axillary, and pubic hair growth. She reported having a shallow vaginal canal and absence of a cervix. All of her siblings had normal sexual development with no reproductive or gynecological disorders, and have been able to conceive without any problems. Review of systems was negative for vision changes, galactorrhea, abdominal pain, urinary or defecation problems however positive for headaches. Patient identified as a lesbian. On physical exam the patient had normal vital signs, height of 164 cm and 86 kg (calculated BMI 32); increased muscular tone; no voice deepening; no abdominal pain; sparse hair in the pubic region, upper lip, chin, and bilateral axillae; and Tanner stage 2 breasts. Genitourinary exam was notable for large labia majora, clitoromegaly, palpable testes in inguinal canal, blind vaginal pouch, and absent uterus and cervix. Labs showed normal estradiol (17pg/mL; male 5-52pg/mL), elevated testosterone (273ng/dL; male 249-836ng/dL, female <45ng/dL), LH (24.5 mIU/mL; male 1.7-8.6mIU/mL), and FSH (39.3mIU/ml; male 1.5-12.4mIU/mL), negative urine pregnancy test, normal prolactin, normal thyroid function tests, and a 46, XY karyotype. Imaging demonstrated absent uterus and ovaries, a short blind-ending vagina, and bilateral testes in the inguinal canals. Given elevated FSH, LH and testosterone levels with virilization, the patient was diagnosed with CAIS and underwent bilateral orchiectomy. After surgery, the patient was started on estrogen hormonal replacement therapy. CONCLUSION: Early diagnosis of CAIS is important as this helps guide pharmacotherapies, surgery, malignancy surveillance, genetic counseling, and psychosocial support; all of which help determine a patient’s sexual identity. This case is interesting because the patient was diagnosed far past menarche in her fourth decade, which proved to be psychologically distressing given the patient was unaware of the presence of testes. As androgen insensitivity syndrome presents on a spectrum and any intervention is dependent on phenotype and patient preference, further research is needed to provide evidence-based guidelines regarding therapeutic intervention in any patient with CAIS.