Run Time: 7 minutes
Author: Greg Burcham M.D.
- Case presentation: A 48 year-old male cyclist travels to new england for a race. Afterwards he is sore, tired and fatigued, but 1 week later back in Colorado he is still sore, tired, and fatigued, and he also noticed a rash that started after a few days. The patient presents to the ED after a syncope with HR in the low 40s.
- This patient has Lyme Disease. Hallmarked by the rash that he has, known as erythema migrans – a migrating red rash.
- Symptoms usually present 1-2 weeks after a tick bite, and generally start as nonspecific – fever, myalgias, headache, arthralgias, malaise. 80% of patients present with the rash that starts as a small red lesion that enlarges with a bright red border.
- A smaller percentage of patient get early disseminated disease. The most concerning complications are cardiac – Atrioventricular Block, bradycardia, and syncope – or a meningitis presentation.
- Late disseminated findings include chronic joint and muscle arthralgias, seizures, paresthesias, memory and cognitive changes. Amy Tan – author of The Joy Luck Club – has chronic lyme and she loses memory if she is off her antibiotics for any period of time.
- Lyme Disease is increasing by more than 10% per year for several years due to the destruction of habitat of predators, leading to mice population explosion, and global warming.
- Each stage of the tick life cycle require a blood meal – larva to nymph to adult. Normally larva find it hard to get a blood meal in the fall after they hatch in the late summer. The larva go dormant until spring when they are able to find a blood meal and eventually become adults so the life cycle can start over on an annual basis.
- As the climate has warmed a higher percentage of larvae are feeding earlier in the year, with a greater frequency in the New England area.
- The bacteria that causes Lyme Disease needs time to replicate in the host, but due to asynchronous feeding between the mice and ticks there is a higher concentration of the bacteria in both the mice and the ticks.
Link to Podcast: http://medicalminute.madewithopinion.com/lyme-disease/