One of your friends, a 25 year old woman, calls you up in the middle of the night panicked because she "peed blood." With a sigh, you go over to her apartment to calm her down. When you examine her urine, you find that it's not blood, just red urine. Weird. You can't quite put your finger on the diagnosis yet, but as you haven't seen her for a while, you two sit around the dining table catching up about the good old college years. As you're talking, you notice that she keeps going to the freezer to get ice cubes to chew on. When she opens her fridge, you see these.
Challenge: That's all I needed to make the diagnosis. What about you?
(I'm kidding, this is a tough Encyclopedia Brown case)
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