This case is adapted from an example on UpToDate. It is the first part to a two part case.
A 20 year old woman with no past medical history presents with weight loss of 10kg over 6 months. She began watching her diet after taking a nutrition class. Her diet now consists of a cup of coffee for breakfast, an apple with a diet coke for lunch, and an organic leafy green salad with a cup of coffee for dinner. She says she hydrates herself well, especially since she runs 5 miles a day. She has one bowel movement a week. Her LMP was 3 months ago, though she denies sexual activity. Her EKG is below.
Challenge: What's the diagnosis?
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