Tick Borne Illnesses Flashcards
symptoms and presentation of babesiosis
NOT the same thing as brucellosis - which is zoonotic dx from cows)
flu like illness with hemolytic anemia and thrombocytopenia and transaminitis
how to diagnose babesiosis
by peripheral smear see Maltese cross or meroziotes arranged in tetrads in RBCs; described as “pleomorphic ring forms with pale blue cytoplasm” Thin blood smear (wright/giemsa stains) PCR = detection of babesia DNA in blood Serology: may be negative in acute infection. they do not grow well on a blood culture.
treatment of babesiosis
azithromycin + atorvaquone or
clindamycin with quinine
Can use IV abx if severe dx
remember this is the exception out of the tickborne dx treatments.
what causes babesiosis
infection with protazoan babesia microti found with same vector as lyme dx with Ixodes tick.
Rash that appears on 3rd to 5th day after onset of fever. Rash starts around ankles and wrists and involves the palms and soles and is usually petechial .
Rocky Mountain spotted fever tx with doxycycline.
treatment of early lyme dx
doxycycline should have resolution of symptoms in 2-3 weeks and rare for treatmetn failure
initial work up for suspected Lyme dx
positive ELISA IgM needs to be confirmed with a Western blot.
post lyme disease syndrome
presents with myaglias, headaches, cognitive complaints weeks to months post initial successful treatment. Treatment is supportive care.
early localized lyme disease
nonspecific viral illness with erythema migrans. can treat.
Do not get acute phase serological testing as IgM is not found until after 2-6 weeks after infection has occurred.
prophylaxis criteria for lyme dx (must meet all 5)
- attached tick is an adult or nymphal Ixodes scapularis (deer tick)
- tick attached for more than 36 hrs or engorged
- prophylaxis started within 72 hrs of tick removal
- local borrelia burgdorferi infection rate >20% (New England area)
- no contraindication to doxycycline (age <8 hrs, pregnant or lactating)
if there’s someone who has a tick found what is first step
tick removal via tweezers and protected hands by pulling straight up
erythema migrans
bull eye rash, seen after acute Lyme infection about 5-10 days after.
treatment for lyme dx prophylaxis
single dose of doxycycline 200 mg. if cannot take doxycycline or refuses most dr do not give another antibiotic. Rather would observe and then treat if EM develops
when do IgM antibodies for lyme dx develop?
2-6 weeks after and so getting ELISA and western blot may have false negatives.
if someone shows up with erythema migrans rash do they need any other testing
no do not need serological testing treat for lyme dx
Treat with doxycycline (200 mg) or cefuroxime or amoxicillin.
Rocky Mountain spotted fever presents with
nonspecific fever, headache, myalgia, arthralgia systemic symptoms followed by several days later by maculopapular petechial rash. No alopecia or LAD Can develop into encephalitis, pulmonary edema, bleeding, and shock.
Ehrlichiosis
tickborne illness seen in southeastern and mid atlantic US. fever with fatigue arthralgias and headaches and splenomegaly. see intracytoplastmic or (Morulae) inclusions affecting neutrophils or WBCs.
high fever, myalgias, headache and nausea/vomiting, LAD and AMS - see a macular or maculopapular petechial rash without central clearing in 30% of pts see intraleukocytic morulae on blood smear
Ehrlichia infection
what causes Ehrlichiosis infections and were are they located?
HGA or human granulocytic anaplamosis - anaplasma phagocytophilium Ixodes tick vector seen in northeastern and midwestern US
HME- Ehrlichia chaffeensis - lone star tick (amblyomma americanum) vector and seen in southeast and south central US with white tailed deer host. seen in spring and summer months
Ixodes tick is a vector for
lyme dx and babesiosis and Ehrlichia infections
Lab findings associated with Ehrlichiosis
leukopenia, elevated transaminases, IFA serologies peripheral blood and buffy coat exams shows intraleukocytic morulae. This infects monocytes not RBCs Can diagnosis via PCR
management of Ehrlichia infections
give doxycycline before the results of serology to come back to prevent complications like seizures and renal/respiratory failure
pt recently visited Connecticut with influenza like symptoms and erythema migrans (rash with central clearing) think:
Lyme dx
if pt is bitten by a tick and develops high fever and and maculopapular rash on trunk without central clearing and see cytopenia (low WBC and platelets) think:
coinfection with anaplasma phagocytophilium or cause of human granulocytic anaplamosis or HGA)
is Rocky Mountain spotted fever serology helpful in acute infections?
negative for first several days of infection and not helpful for making clinical decisions if concerned treat empirically cause untreated can cause death.
Rocky mountain spotted fever rash evolution
starts on ankles and wrists and spreads centrally and to palms and soles. Seen as a petechial rash
when should treatment for Rocky Mountain spotted fever start
after 5 days of symptoms can see encephalitis.
which pts are at great risk for severe Babesia infections? what are the complications for severe Babiosis infection?
greatest risk for severe Babesia infection: Asplenic pts, HIV, immune suppressed
Complications are: CHF, ARDS, DIC, AKI liver failure, splenic rupture.
anaplasma phagocytophilum is a result of
human granulocytic anaplasmsosis HGA and caused by Ixodes scapularis. See intracytoplasmic inclusions in granulocytes
how do people get babesiosis
from tick transmission (Ixodes scapularis) or blood transfusion