Insect Bites/Parasites Flashcards
most easily seen nape of neck and above the ear - nits (eggs) can be found attached to hair shaft
pediculosis
lice tx?
permethrin 1% cream
for resistant bugs use malathion or oral ivermectin in immunocompromised
presents as severe pruritus 4-6 weeks after initial infestation
- excoriations of the web spaces, heel of the palm, wrist, elbows, axillae, genitalia and breasts
- head and neck infection in infants, elderly and immunocompromised
- burrows can be found with associated small vesicles and pustules
scabies
who to treat when scabies are present?
entire household
scabies tx?
permethrin 5% cream to entire body for 8-12 hours, repeat 1 week later
immunocompromised tx of scabies
oral ivermectin, 1 dose
crusted scabies tx?
ivermectin once a day on days 1, 2, 8, 9, 15 plus permetrhin daily for 7 days, then 2x a week till cured
how to tx a scabies pt that has intense itching?
topical steroids or benadryl
main tx for arthropod bites?
topical steroids
breakfast, lunch, dinner bite
bed bugs
how long must a tick be attached for risk of lymes disease?
must feed for at least 24 hrs to infect host, but 72hrs is more statistically significant
stage 1 lymes
Classically an expanding bull’s eye erythematous lesion (erythema migrans)
Associated w/ flu symptoms w/ or w/o fever (HA, arthralgias, myalgias, fatigue)
stage 2 lymes
can occur 1-4 weeks after EM
Neuro: Bell’s Palsy, “aseptic” meningitis (mild)
Cards: myopericarditis w/ atrial or ventricular arrhythmias or heart block
stage 3 lymes
manifests primarily as musculoskeletal, neurologic and skin sx/symptoms
- classically presents as monoarticular or oligoarticular arthritis with the knee disproportionately swollen compared to pain
Acrodermatits chronica atrophicans
blue/red discoloration -> atrophic and sclerotic
rare side effect that can occur up to 10 years later
gold standard test for lymes
B. burgdorferi culture
confirmatory test for lymes
western blot
most accessible test for lymes
Indirect Immunofluorescence Assay (IFA)
IgM and IgG results from lyme
IgM-first appears 2-4 weeks post-exposure
- peaks at 3-6 weeks
IgG-first appears 4-6 weeks post-exposure
- peaks 4-6 months
how is early lymes actually diagnosed?
cliniwhecal symptoms
how is late lymes dx?
clinical symptoms and lab testing
what if the pt has non-specific symptoms?
no lab testing required
under what cirucumstances would you begin lymes prophylaxis?
- adult or nymph I. scapularis identified and known to be attached for 36hrs
- prophylaxis is started within 72hrs of tick removal
- more than 20% of ticks in area known to be infected w/ B. burgdorferi
- no contraindication for doxycycline (pregnant, allergic, 8 or younger)
stage 1 tx?
Doxycycline 100mg BID x2-3 weeks
