Diagnostic Chelation Challenge with DMSA: A Biomarker of Long-Term Mercury Exposure?
Howard Frumkin,1 Claudine C. Manning,2 Phillip L. Williams,3 Amanda Sanders,1 B. Brooks Taylor,4 Marsha Pierce,4 Lisa Elon,2 and Vicki S. Hertzberg2
Department of Environmental and Occupational Health, 2Department of Biostatistics, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
Department of Environmental Health Science, University of Georgia, Athens, Georgia, USA
Coastal Health District, Georgia Division of Public Health, Brunswick, Georgia, USA
Chelation challenge testing has been used to assess the body burden of various metals. The best-known example is EDTA challenge in lead-exposed individuals. This study assessed diagnostic chelation challenge with dimercaptosuccinic acid (DMSA) as a measure of mercury body burden among mercury-exposed workers. Former employees at a chloralkali plant, for whom detailed exposure histories were available (n = 119) , and unexposed controls (n = 101) completed 24-hr urine collections before and after the administration of two doses of DMSA, 10 mg/kg. The urinary response to DMSA was measured as both the absolute change and the relative change in mercury excretion. The average 24-hr mercury excretion was 4.3 µg/24 hr before chelation, and 7.8 µg/24 hr after chelation. There was no association between past occupational mercury exposure and the urinary excretion of mercury either before or after DMSA administration. There was also no association between urinary mercury excretion and the number of dental amalgam surfaces, in contrast to recent published results. We believe the most likely reason that DMSA chelation challenge failed to reflect past mercury exposure was the elapsed time (several years) since the exposure had ended. These results provide normative values for urinary mercury excretion both before and after DMSA challenge, and suggest that DMSA chelation challenge is not useful as a biomarker of past mercury exposure. Key words: biomarkers, chelation, chloralkali, DMSA, environmental diseases, mercury, neurotoxicity, occupational diseases, renal toxicity, succimer. Environ Health Perspect 109:167-171 (2001) . [Online 25 January 2001]
from article on Dr Bolte, page 4:
"Another patient, an art gallery owner, arrived one day complaining of chronic headaches that he’d had for 40 years. His primary care physician had him on six different medications, some prescribed for migraines, others for depression, and still others for the side effects from the migraine meds. The suffering was so severe that the patient took to bed for days at a time, tracking his headaches on a calendar, hoping to divine a pattern to the pain. Some days the meds worked, some days they didn’t. But no pattern emerged. Every doctor he saw seemed to be grasping at straws: One prescribed an antifungal medication; another, allergy shots. Bizarrely, Bolte seized upon a single symptom: The man casually mentioned an intolerance to egg yolks. If true, this seemingly innocuous point could narrow his problem down to only one or two possible diagnoses, one of them being heavy metal poisoning. Sifting through the file, Bolte found a hair analysis that the desperate patient had commissioned at an alternative pharmacy: The results showed elevated levels of mercury. Yes, the patient said, he had shared that result with his original doctor, who pooh-poohed the test and told him that if he was concerned about it, he might want to reduce his fish intake. Bolte ordered a DMSA challenge test, in which a drug is taken orally that extracts heavy metals—if they exist—from tissues and excretes them in urine. The urinalysis revealed extremely high levels of mercury. The man responded well to medication and a new diet that flushed much of the dangerous toxin out of his body. Two years later, he celebrated his first headache-free month."
This article on Bolte, linked above, is worth reading to see what kind of medical practice one doctor has established in NYC. In order to get an appointment you have to agree to his terms, $125 for a 25 minute urgent care visit or over $300 for an hour intensive interview. He doesn't take insurance, and he asks each patient to fill out a 32 page questionnaire after their first visit.
The document inquires about family medical history, social history, habits, hobbies, employment, exposure to household products, industrial chemicals, foreign travel, and lots more. "Bolte estimates it takes two to four hours to complete. He does not apologize for such complicated homework. Humans are complex, and a doctor never knows until much later if a patient’s response was significant or just a red herring."
I have already begun compiling the questions that I will use in such a form. How to organize them is the question.
And below, a comment pulled from an LJ user who went to Bolte:
He is wonderful! I usually hate doctors; they always dismiss me, and appointments are like 15 minutes. I had a rheumatologist who would have cost me around $350 for 15 minutes, had I not had insurance. In comparison, and for what its worth, Bolte is much, much, much more worth it (same price, more time). Well first, let me say that getting him on the phone is nearly impossible! Also, he really wants to know his patients care about getting an appointment. He asks for a mailed written letter prior to consultation, describing symptoms, and he prioritizes his patient list. He is also VERY busy. I tried calling him for a second appointment several times before he had time to pick up . . .
I went once for the initial patient analysis. When I first arrived, he gave me the long survey and told me it would be my homework. Then, I went a second time to get my results! He was very nice. He remembered everything I told him during the first visit- down to that I was an intern, and where I went to school.
I was sort of taken aback by it, because I had never been treated that way before by a doctor. He asked me about school, my friends, my family, and shared anecdotes about his own life. I felt very awkward initially because I wasn't sure how asking me personal questions would elicit any results. He's a clever man, though, so throughout everything, he asked things in reference to what I had for lunch and breakfast, which I didn't think important at all, and he asked if I cooked/whether my parents cooked and if they cooked well/what I ate. He went through my medical records while I sat there and he would occasionally crack jokes -- we talked about politics, the news, my perspectives on things. He did a quick check-up, we continued talking. At the end, based on what I'd said (he listened to me!), he decided to run some tests on me. He also put me on the most restrictive diet of my life (wheat free, sugar free, dairy free, yeast free). It was a very long initial consult, but I liked it and towards the end didn't really want to leave.
He really did get to know me pretty well. When I went in for my second appointment, he said, "I am really glad you came to me. I cannot believe nobody else believed this or saw this in you. You really made the right decision." He remembered me, he didn't have to look at my files to remember my symptoms/test results, and he continued talking to me about both my results and other stuff in general. I handed him the survey I filled out, he read it all, and said the symptoms, the results, my history-- everything-- point directly to celiac. He also asked me if I was thinking of going into medicine now since I went into so much trouble finding a doctor that would actually diagnose me (and since I knew a bit more about autoimmune issues/celiac disease than the average person does).
After six months of the diet, I have another appointment with him. To be honest, I'm sort of sad that it will probably be the last time I see him, lest something comes up.