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Editorial – Last December, I posted a Viewpoint titled “Gadolinium Retention – Is it all in my head?” When I wrote that, I believed I had retained gadolinium in my brain, thyroid gland, and various other parts of my body. I believed it, but I did not know it for sure. It is one thing to think it, but it causes totally different feelings when you have confirmation that you have retained a toxic metal in your body.
On April 8, 2015, I posted about the gadolinium found in my thyroid tissue that was removed 51 months after my 5th dose of a linear gadolinium-based contrast agent. In July, I learned that an analysis of my 2012 non-contrast brain MRI found evidence of gadolinium deposition in the globus pallidus; that MRI was performed exactly two years after my last dose of contrast. Because of recently published studies, I was not surprised that they detected residual gadolinium in my brain. At the time of my MRIs, except for hypertension and a past history of migraine headaches, I had no history of anything known to alter the blood-brain barrier. Then and now, I continue to have “normal” renal function with an eGFR >60, but yet, I have evidence of long-term retention of gadolinium in my body. If I only had gadolinium in my tissues and no symptoms, I might not worry about it as much, but that is not the case. (more…)
Today, July 27, 2015, the FDA issued its initial Safety Announcement concerning possible safety risks caused by brain deposits of Gadolinium following repeated use of Gadolinium-based contrast agents for MRIs. A link to the document on the FDA website is provided below. The following is the FDA’s Safety Announcement:
FDA Drug Safety Communication: FDA evaluating the risk of brain deposits with repeated use of gadolinium-based contrast agents for magnetic resonance imaging (MRI)
The U.S. Food and Drug Administration (FDA) is investigating the risk of brain deposits following repeated use of gadolinium-based contrast agents (GBCAs) for magnetic resonance imaging (MRI). MRIs help detect abnormalities of body organs, blood vessels, and other tissues. Recent publications in the medical literature have reported that deposits of GBCAs (See Table 1) remain in the brains of some patients who undergo four or more contrast MRI scans, long after the last administration.1-21 It is unknown whether these gadolinium deposits are harmful or can lead to adverse health effects.
FDA, including its National Center for Toxicological Research (NCTR), will study this possible safety risk further. We are working with the research community and industry to understand the mechanism of gadolinium retention and to determine if there are any potential adverse health effects. Based on the need for additional information, at this time, we are not requiring manufacturers to make changes to the labels of GBCA products.
To reduce the potential for gadolinium accumulation, health care professionals should consider limiting GBCA use to clinical circumstances in which the additional information provided by the contrast is necessary. Health care professionals are also urged to reassess the necessity of repetitive GBCA MRIs in established treatment protocols.
Patients, parents, and caregivers should talk to their health care professionals if they have any questions about the use of GBCAs with MRIs. This issue affects only GBCAs; it does not apply to other types of scanning agents used for other imaging procedures, such as those that are iodine-based or radioisotopes.
After being administered, GBCAs are mostly eliminated from the body through the kidneys. However, trace amounts of gadolinium may stay in the body long-term. Recent studies conducted in people and animals have confirmed that gadolinium can remain in the brain, even in individuals with normal kidney function.1-21 Available information does not identify any adverse health effects.
We urge health care professionals, patients, and parents/caregivers to report possible side effects involving GBCAs to the FDA MedWatch program, using the information in the “Contact FDA” box at the bottom of the page.
The list of approved GBCAs (Table 1), Data Summary, and References included with this FDA Communication can be found here: http://www.fda.gov/Drugs/DrugSafety/ucm455386.htm
Patients who believe they have been adversely affected by an MRI contrast agent should report their experience to the FDA using its MedWatch Adverse Event Reporting System which can be found here: http://www.fda.gov/Safety/MedWatch/default.htm
Editorial – I believe the FDA needs to do more to regulate the use of linear and macrocyclic gadolinium-based contrast agents administered for enhanced MRIs and MRAs.
Since January 2014, I am aware of nine studies that have reported finding evidence of gadolinium deposition within the brain tissues of patients exposed to gadolinium-based contrast agents or GBCAs. In most of those studies, the patients did not have severe renal disease, in fact, most were described as having “normal renal function” or an eGFR >60. Despite the increasing number of new studies that indicate that gadolinium is remaining in the brain, some still question whether there is any clinical significance. Speaking as someone who has been adversely affected by retained gadolinium, I believe that there is clinical significance, and I am not alone. Members of our MRI-Gadolinium-Toxicity support group have reported symptoms that are consistent with what is known about the toxic effects of gadolinium. Since we released the results of our 2014 Survey of the Chronic Effects of Retained Gadolinium from Contrast MRIs, our support group has almost tripled in size and another affected patient recently started a group on Facebook. I believe the problems related to gadolinium retention are significant, but they are not being recognized. (more…)
So why am I talking about an iceberg on the Gadolinium Toxicity website? Let me explain.
Not long after I started researching NSF and Gadolinium in early 2010, I saw a reference to an editorial by Dr. Henrik Thomsen of Denmark that had been published in 2008. The title was, Is NSF Only the Tip of the “Gadolinium Toxicity” Iceberg? The title caught my attention and really made me think. It took me a while, but I finally managed to find the editorial. After reading it, I had more questions than answers.
It seems that in the early 1990s, there was already concern about the stability of the nonionic linear GBCAs, and the macrocyclic agents were found to be significantly more stable in serum. It was known that transmetallation with other metal ions in the body was more apt to occur with the DTPA-based chelates, and when transmetallation occurs it results in the toxic Gadolinium ion remaining in the body. Dr. Thomsen asked, “Why were nonionic linear chelates chosen instead of macrocyclic chelate?” That is a very good question.
For those of us in the U.S., a better question might be, why did it take the FDA longer to react than the European Medicines Agency (EMEA) and the Japanese authorities? (more…)