methimazole and agranulocytosis

[kimmjmc]

56-year-old female here dx'd with Graves disease and resultant HTN.  I've been on propanolol and methimazole since last October.  Now I'm only taking 5 mgs daily of methimazole and am probably only paranoid about having a reduced white blood cell count.  The last week I've been fatigued again, starting having sore gums a few days ago, and tonight I went to an Urgent Care for a nasty, painful patch of cellulitis on my lower buttock.  Although I told the MD the medications I was taking, he didn't mention drawing blood for a CBC, although I did get an antibiotic injection and a script for Bactrim and circle drawn around my cellulitis lesion.  Am I totally out of line to worry about possible granulocytopenia?  I know it's very unlikely on only 5 mgs.  So should I not worry at all unless I also develop a fever and sore throat, which according to the internet, are the classic symptoms of reduced granulocytes?  Thanks.

[kimmjmc]

Thank you, Dr. Lupo.  On March 6th I returned to the Urgent Care doctor.  He referred me to the emergency room, as it seemed the cellulitis was not responding to the oral antibiotics and he thought I may need IV antibiotics.  The emergency room PA said I just needed the wound incised and drained, which he performed.  However, at the ER, once again I gave a list of the meds I am on (including methimazole), but no labs were ordered.  I guess I should call my endocrinologist for the CBC.  Thanks again for the reply and the information.

[Mark Lupo, M.D.]

Yes - you need a CBC to check WBC (especially the "granulocytes") in the setting of any infection while on anti-thyroid meds.