Lyme dz Flashcards
Which stage of the tick is most infectious for spreading lyme? Which months are the worst?
Nymphs. June-Early August are the worst months
What is the most common vectorborne illness?
Lyme dz
What do you see in early Lyme disease?
Erythema Chronicum migrans (50%)
plus flu like symptoms
What do you see in late Lyme disease?
Arthritis (30%)
Neurologic Sx (meningismus, cranial nerves, radiculopathy)
Cardiac (5%)
How do you tell the difference between Lyme and viral meningitis?
Lyme is afebrile, illness over a week, Low polys (<10%), cranial palsy, ERYTHEMA CHRONICA MIGRANS
What happens in untreated lyme dz?
Progresses to:
- Chronic arthritis
- Post Lyme disease syndrome (fatigue and arthralgias lasting 6 mos)
- Atrophic lesions of the skin
Does chronic lyme disease exist?
Similar to controls in ability to perform ADL. No clinical/lab evidence of current or past infection
How do you diagnose Lyme dz?
ECM+exposure to an areas with Lyme is enough to make a diagnosis (50%)
Can use serology if presents with CN deficits/neuro symptoms.
What is the problem with using lyme disease serology (ELISA)?
FALSE positives
- Positive from past exposures
- X-reacts with other spirochetes (syphilis)
- In early Lyme dz, NEGATIVE. Only turns positive after 6-8 weeks
- –>THEREFORE EARLY LYME=CLINICAL DX
If you have a positive ELISA, what other test would help confirm?
Get a positive IgG and IgM on ELISA…
Then confirm with a western blot.
Why would you not perform serology in a Lyme endemic area?
Because so many of the patients will be positive anyway from past exposure…
What is the main reservoir of borrelia burgdorfi?
White footed mouse
What is the role of deer in borrelia?
To transport the infected ticks around, spreading the disease
How do you treat early lyme dz?
Doxycycline or amoxacilin for 10-14 days
How do you treat late lyme dz?
Doxycycline or ceftriaxone/penicillin IV for 14 days
