A 16-year old girl was brought with primary amenorrhea. Her mother mentioned that she staed developing breast at the age of 12. She was prescribed OCPs 2 years back by a doctor with no effect. She was having normal stature and was a football player. On examination, breasts were well developed (Tanner's stage 5) and pubic hair was minimal (Tanner's stage 1). What is the most probable diagnosis?
Premature ovarian failure
Turner's syndrome
Miillerian agenesis
Androgen insensitivity
Ans: D. Androgen insensitivity(Ref: Shawl 16/e p141, 15/e p111-112; Novaks 14/1037-1038; Dutta Gvnae 6/e p424)Most likely diagnosis here is androgen insensitivity syndrome.Androgen Insensitivity Syndrome:Also referred as "Testicular feminization".An X-linked recessive condition.Results in failure of normal masculinization of external genitalia in chromosomally male individuals.Testes produce normal amounts of mullerian-inhibiting factor (MIF), also known as mullerian-inhibiting substance (MIS) or anti-mullerian hormone/factor (AMH/AMF),Features:Absence of fallopian tubes, a uterus, or proximal (upper) vagina.Identified in newborn period - By presence of inguinal masses & later identified as testes during surgery.Sometimes diagnosed in teenage years during primary amenorrhea evaluation.Absence of pubic & axillary hair in adolescent patients.Scanty body hair & lack of acne.Yet normal breast - Due to testosterone to estradiol conversion.