I was working yesterday in Fast Track when a younger male came in with a rash almost identical to the one above. I found this picture on google so I included it here (I’m still trying to work out the kinks of posting patient photos on the blog.) As most of you can guess, this is a pretty classic erythema migrans rash seen in patients with Lyme Disease. I was pretty surprised because I haven’t seen this since I left North Carolina where I did my residency. It turns out this guy was a forester and had been hiking in Ohio and Pennsylvania. He believes however that this tick was from his Ohio hike. This illustrates that while it is rarely seen in Ohio, it happens, so we need to be on the lookout!
Here are some key take-home points for the diagnosis and management of Lyme disease:
The tick is the Ixodes aka the deer tick.
It is a spirochetal infection caused by Borrelia species, B. burgdorferi
There are three stages
1. Early localized- erythema migrans with or without constitutional symptoms–few days to one month
2. Early disseminated-multiple erythema migrans rashes and/or cardiac (atrioventricular block and myocarditis) and neurological symptoms (encephalopathy, peripheral neuropathy, and encephalomyelitis)
3. Late- intermittent or persistant arthritis (especially larger joints like the knee), neurological symptoms such as encephalopathy or polyneuropathy
Dosing — Dosing of antibiotics for early Lyme disease is as follows:
- Doxycycline 100 mg orally twice daily for adults; 2 mg/kg twice daily (maximum 100 mg dose) for children ≥8 years of age
- Amoxicillin 500 mg three times daily for adults; 50 mg/kg per day in three divided doses (maximum 500 mg per dose) for children
- Cefuroxime axetil 500 mg twice daily for adults; 30 mg/kg per day in two divided doses (maximum 500 mg per dose) for children
The duration of treatment is typically 21 days but some studies have shown that 10-14 days is as effective.
For this patient, we placed him on doxycycline 100mg twice daily for 21 days.