Showing posts with label usmle step 1. Show all posts
Showing posts with label usmle step 1. Show all posts

Thursday, May 18, 2017

Repeated USMLE Questions Step 1 - 152






A 17 year-old girl visits the clinic with her mother who is concerned that her daughter had not menstruated yet and her breast had not been significantly developed. She also notes that her daughter is color blind. The girl denies any sexual relationship or using any recreational drugs. Examination reveals normally appearing girl with small non-developed breasts. There is lack of pubic hair and her vagina and cervix are not fully developed. She is 5f5in tall and weighs 130 Ib. Cardiac, chest and abdominal examinations are unremarkable.

What is the most likely initial diagnosis?

A-Androgen insensitivity disorder

B- Early pregnancy

C- Kallmann’s syndrome

D- Kartagener’s syndrome

E- Turner’s syndrome

Answer






This patient has primary amenorrhea, delayed secondary sexual development and color blindness. All these features are characteristic of Kallmann’s syndrome. It is a hereditary disorder of GnRH synthesis. Androgen sensitivity disorder is characterized by the development of breasts and female external genitalia in an XY candidate. This patient has primary amenorrhea and under-developed secondary sexual characteristics which exclude pregnancy. Kartagener’s syndrome characterized by recurrent respiratory tract infections due to lack of cilia and infertility in men due to defective sperm movement. Turner’s syndrome is characterized by amenorrhea and lack of secondary sexual characteristics. It is excluded in this case because it causes dysmorphic body shape and short stature which are not available in this case.

The correct answer is C