Chelation Use and Illness
January 12, 2015 – We would like to offer this advice from our Medical Advisory Board Chair, Dr. Ellis Neufeld, concerning some situations in which one may need to consider temporarily halting chelation therapy while treating another issue:
1. As a general rule, patients should always halt chelators (any chelator) temporarily for fever, and call their chelator prescriber or on call doctor to report the fever, at any hour of the day or night.
a. Patients whose spleen has been removed must also be seen promptly for fever over 101.5F (38.5C) because of the higher risk of bacterial infection.
b. Patients on Ferriprox (deferiprone) with fever must not only temporarily halt chelator, but also go promptly for blood counts, because of the small but important risk of neutropenia (low levels of neutrophils) with Ferriprox.
2. Patients with any significant, new clinical events, even without a fever, should halt their chelator until they talk to their provider. Examples of such events might include changes in vision or hearing, significant vomiting or diarrhea which is new or severe (as opposed to chronic and/or mild), lethargy, respiratory distress, worse jaundice, abdominal pain, joint pain and so on. Chelators are less likely to cause some findings on this list than others, but it never hurts to call.
3. In general, a “sniffle” or obvious cold virus without fever, or vomiting once or twice in a child, or mild loose stools, would not require stopping chelator if no fever is present. Parents should have a reliable fever thermometer available for monitoring.
In terms of what constitutes a fever, we recommend asking your hematologist or thalassemia nurse how your center defines “fever” for this purpose. It depends somewhat on the age of the patient, and can depend on the method of taking the temperature. For example, some centers might use 38C (100.5F roughly), and others 101F. There’s no one firm answer because the risk to the patient isn’t the height of the fever itself, but rather the degree to which the fever reflects an underlying disease. For the purpose of patients with no spleen requiring evaluation, from toddler age on up through adulthood, Dr. Neufeld’s center uses 101.5F (38.5C). We will try to poll the medical advisory board on this question and report back through the Foundation.