David
Co-Founder
I recently asked,
Emmanuelle Williams, MD is the Assistant Director for Clinical Medicine and Education, Hershey/Penn State IBD Center.
In regards to the question, Dr. Williams stated:
Thank you to Dr. Williams for her time and expertise!
Doctor Emmanuelle D. Williams, M.D. of the Penn State Hershey Inflammatory Bowel Disease Center took time out of her busy schedule to answer this question. A little about Dr. Williams:Do you routinely test people with Crohn's disease for vitamin B12 deficiency? Why or why not? What is the minimum B12 level you want people with Crohn's disease to have? And do you test serum B12, methylmalonic acid, or something else?
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Emmanuelle Williams, MD is the Assistant Director for Clinical Medicine and Education, Hershey/Penn State IBD Center.
In regards to the question, Dr. Williams stated:
WHY DO WE TEST?
B12 deficiency can cause a wide variety of symptoms that can be detrimental to the quality of life of IBD patients. These symptoms include but are not limited to fatigue, irritability, depression, memory impairment, and neurologic symptoms. Beyond quality of life, it is critical to recognize and treat vitamin B12 deficiency as it is a reversible cause of bone marrow failure anemia and demyelinating disease. In our clinic, we have a low threshold to test for B12 deficiency and routinely assess vitamin B12 status in all IBD patients at risk for B12 deficiency. These patients not only include those with known risk factors for B12 deficiency such as a history of small bowel involvement, small bowel surgery, small bowel bacterial overgrowth, Ileal Pouch Anal Anastomosis, age over 65, strict vegetarians, patients who have macrocytic anemia, or anemia that is not responsive to iron but ALL patients who appear to be symptomatic.
HOW DO WE TEST?
Traditionally, the diagnosis of B12 deficiency has been made on the basis of B12 below the ‘normal’ level of 200pg/mL along with clinical findings. However in the general population this method can miss up to 50% of patients with deficiency. This is even further compounded in the IBD population, in whom clinical symptoms of B12 are missed as they are assigned to their bowel disease, and who also may have falsely normal B12 levels due to small bowel bacterial overgrowth and/or an active inflammatory state. Elevation of Methylmalonic Acid (MMA) has been found to be a more sensitive and earlier marker of B12 deficiency and can aid in the detection of B12 deficiency well before clinical signs develop. In patients who have a B12 below 400 pg/mL, as in most of our tested patients, we additionally test MMA. Folic acid is also tested as it can cause low levels of B12. MMA is then used to monitor response to treatment with a goal of normalizing MMA, reducing symptoms and at the very least reaching 200pg/mL of B12.
HOW OFTEN DO WE TEST?
There are no established recommended intervals for screening. In our clinic we make sure our at risk patients are screened on a yearly basis.
HOW DO WE TREAT?
There are few if any adverse consequences to over treating B12 deficiency, and we do not hesitate to initiate treatment for patients. We use 1mg of B12 subcutaneously weekly and then continue the same dosing monthly indefinitely with monitoring of treatment 3 months after treatment is initiated. We do not treat with oral replacement as this is often poorly absorbed in our patient population, and we do not use nasal formulations which are very expensive and rarely covered by insurance plans. We find that the majority of patients greatly benefit from treatment.
BOTTOM LINE
While B12 deficiency and treatment may not significantly change the natural course of our patients’ underlying bowel disease we feel that this can have a significant impact on our patients’ well being and we urge them to have close monitoring by their treating physician.
Thank you to Dr. Williams for her time and expertise!