An 8-year-old female started having anxiety, gut pain, and problems with non-replacing hair loss at 4 years old. No history of food poisoning or anything out of the ordinary. She was breastfed to a year. Psychiatrist ran blood work, looking for possible vitamin issues, and found hypervitaminosis B12, 1,200 with no supplementation. Immediately sent her to MD, as most of the time the cause is something neoplastic. She was checked and cleared from there. She had colonoscopy and endoscopy with normal results. Ultrasound of abdomen was normal in August. They tried biotin, but it didn’t help her hair. If it falls out, it doesn’t grow back, so they don’t brush her hair, and it was very infrequently. She almost has dreadlocks, and her hair is thick and coarse. Her B12 levels are steadily increasing. Most recently one was 1,700, and she is paradoxically having symptoms of hypovitaminosis B12. She had a mouth lesion that had to be cut out in March, but she had problems recovering from the anesthesia. They are pretty Paleo, but do eat some gluten. They tried gluten free for three months, showed no changes. Blood work doesn’t show much of anything either. Liver markers are normal. Trying to figure out what’s causing it—methylation issues, detox pathways, gut. I’ve mentioned Arrays 3 and 4, but they’re strapped for cash. Any ideas on where to go from here? Stool or SIBO?

Chris Kresser:  Yeah, you mentioned the word that was first on my mind. In some cases, we’ve seen high levels of serum B12, which measures total cobalamins in a context of deficiency of active B12, so looking specifically at methylcobalamin. In fact, if we see high levels of serum B12 on a test and the patient is not supplementing and cancer has been ruled out, then the next thing we’re going to do is we’re going to look at active B12 levels. I would run a homocysteine test. I would run both serum and urine methylmalonic acid, and if you have access to holotranscobalamin as a marker… I wish we did. I hear that it’s starting to be ruled out at some Quest locations. It’s listed in Quest’s online catalog, so I know it’s somewhere! It’s in the database and may be offered in some places, but it’s not offered regionally here. Holotranscobalamin is the most sensitive marker for active B12 deficiency. I would definitely do the homocysteine, and I would do serum and urine methylmalonic acid. I’m assuming she has had a complete blood count, but if she has, you would want to look at her MCV and MCHC, and you’d want to see if those are high or even high normal. If her red blood cells and hemoglobin and hematocrit are even low normal, that’s starting to trend towards macrocytic anemia, which would be indicative of active B12 deficiency.

That’s probably the thing that I would look at next. Certainly, of course, all of the other things that you mentioned would be good to do, as well, but you mentioned that they’re strapped for cash and a lot of those tests cost money. I think the very next thing I would do, given the specificity of the presentation with high serum B12 levels, is to check all of those markers that I just mentioned.