Ehrlichia: confusing cousins, the blood supply, and the new kid on the block 05/04/2012
Posted by thetickthatbitme in Diagnosis, TBI Facts.Tags: Blood donation, Blood transfusion, CDC, Ehrlichia, health, Lyme Disease, medicine, Minnesota, Rocky Mountain Spotted Fever, tick, Wisconsin
5 comments
Ehrlichia…I just met a girl named Ehrlichia…and suddenly the sound…
Nope. Doesn’t quite work.
Ehrlichia is actually named after German microbiologist Paul Ehrlich (1854-1915), who won the Nobel Prize in 1908. Here are some things you actually need to know about Ehrlichia:
1. Ehrlichia is transmitted through the bites of lonestar ticks and deer ticks. If you’ve had another infection carried by these ticks (like Lyme Disease), your doctor should have had you tested for Ehrlichia (or maybe you’ll be asking him/her to test you after reading this post?).
2. Symptoms of Ehrlichiosis include: fever, headache, chills, malaise, muscle pain, nausea / vomiting / diarrhea, confusion, conjunctival injection (red eyes), and rash (in up to 60% of children, less than 30% of adults). When it goes untreated (or improperly treated), complications can include breathing problems, bleeding disorders, and death (1.8% of cases).
3. Ehrlichia is effectively treated with doxycycline in both adults and children. The CDC recommends a 7-14 day course.
4. Your doctor shouldn’t wait for your test results to come back before prescribing you doxycycline. If your doctor thinks you might have Ehrlichiosis, he/she might order a PCR, a blood smear, or an IFA (antibody test). These tests can take a few weeks to come back, and in that time, you could get very, very sick. In addition, a negative result on any of these three tests does not rule out the possibility of infection. Often, in the first 7-10 days you are infected, you will test negative. For more information about these tests, take a look at the Ehrlichiosis fact sheet.
5. Ehrlichia can be easily misdiagnosed as one of two other infections. It’s a rickettisial disease, which means it’s in the same family with A. phagocytophilum and Rocky Mountain Spotted Fever (RMSF). Sometimes the rash patients get with Ehrlichia looks a lot like the rash patients get with RMSF.
6. It may be possible to contract an Ehrlichia infection through a blood transfusion. The CDC has not been very vocal about it, but it’s on their website. Fun fact: “Ehrlichia chaffeensis has been shown to survive for more than a week in refrigerated blood.” If you’ve had an Ehrlichia infection, it’s probably not a good idea for you to be a blood or organ donor.
7. There’s a newly identified species of Ehrlichia in Wisconsin and Minnesota. It doesn’t have a fancy species name yet, so scientists refer to it as Ehrlichia Wisconsin HM543746 or Ehrlichia muris-like (EML). This one is carried by deer ticks. If you live in one of these states and your doctor is not so hip to the new infectious disease research, he or she may have told you that you didn’t need to be tested for Ehrlichia because “we don’t have that here.” (I hate it when doctors say that!)Hopefully there will be a commercially-available, species-specific test for this soon. For now, my guess is that physicians in Wisconsin and Minnesota who suspect Ehrlichia infection are ordering tests for E. chaffeensis and E. ewingii.
Got an Ehrlichia story you’d like to share? Shoot me an e-mail.