11 Comments
User's avatar
Kris Dahlstrom's avatar

When I was young my good friend had xanthromas on her knees,elbows, and between her fingers and toes. She never told me why. When she was 25 she went to a dance with her hubby, leaving her 6 month old daughter with a sitter. She had a heart attack at that dance and died. It was a while before I knew what her disease was and that she had been told it would be best to not have children.

James H. Stein, MD's avatar

Tragic. I’m so sorry.

Dr. Khadija Siddiqui's avatar

Fascinating reminder that not everything that looks like a common lipid disorder actually is, getting the underlying cause right early can completely change long-term vascular risk and outcomes.

James H. Stein, MD's avatar

I agree - thanks!

Viktor Totev's avatar

Thank you for the amazing article!

James H. Stein, MD's avatar

Thank you!

_yuan_'s avatar

Why are the “normal” numbers here so much higher than what Mayo Clinic test results consider “normal”? i.e sitosterol normal numbers should be 1.5mg/dL?

James H. Stein, MD's avatar

The units differ between labs: Mayo reports in mg/L, and the lab we used reports in mg/dL, so Mayo's upper limit of 15 mg/L equals 1.5 mg/dL, which is less than 5 mg/dL used in our reference lab. Reference intervals for plant sterols also vary across labs depending on the assay and the population used to establish the normal range. Neither difference affects the interpretation here; the patient's values were dramatically elevated by any measure.

_yuan_'s avatar

yes, but it’s confusing if one wants to understand how bad/ impactful one’s number is. For example, My Sitosterol is at 27.6 mg/L right now (after medicine). Should I work extra hard (through diet) to push it down further? Hard to balance risk/ reward, though I do understand the data here is limited.

James H. Stein, MD's avatar

I cannot provide medical care on Substack, but that value is high by either reference range. Look at the lab that performed the test and use that as a reference for discussing with your care provider. I am not aware of target values for treatment.

_yuan_'s avatar

Yes, I don’t think there is a target value for treatment, which makes these differing “normal range” more confusing.