Lymes and Ehrlichia etc.

Question 1

Which ticks carry lymes?

Answer 1

backlogged tick: Ixodes scapulars or Ixodes pacificus

Question 2

When is infection most common during the year and by which life stage?

Answer 2

nymphal stage are hungry in the early summer and they are easy to miss since they are small, they demonstrate the highest risk for transmission

common in wooded areas, commonly associated with white tailed deer “deer tick”

Question 3

What is the amount of time that a tick must be attached to transmit the disease?

Answer 3

attachment time is critical and must be at least 24hrs. commonly 36-48 hours; incubation time is 7-14d

Question 4

When is antibiotic prophylaxis recommended?

Answer 4

single dose of doxycycline if
the attached tick can be ID’d as a nymph or adult I. scapularis that has been present for at least 24h and has been removed within 72 hours after
AND the local tick infection rate is greater than 20%

not indicated in children or in pregnant women

Question 5

Describe the symptoms of the early local phase of lyme’s disease.

Answer 5

early localized: erythema migrants, fever, chills, malaise, headache, joint and muscle pain (flu-like); dx made on clinical features and exposure risk

Question 6

Describe the symptoms of the early disseminated phase of lyme’s disease.

Answer 6

(days to weeks after bite)
early disseminated: multiple EM lesions, MSK migratory pain, meningitis, facial nerve paralysis (Bell’s palsy), new and changing AV block, ocular manifestations

Question 7

Describe the symptoms of the late disseminated phase of lyme’s disease.

Answer 7

(months after bite)
intermittent attacks of large joint arthritis (can be chronic), encephalophahty (changes in cognition, sleep, personality), polyradiculophath (spastic paresis, ataxia- like syphillis) and fatigue

Question 8

What are the characteristics of lyme meningitis? How is it treated?

Answer 8

aseptic meningitis profile: lots of lymphocytes, normal glucose and elevated protein

lyme specific Ab will be present in CSF
head, neck pain/stiff, CN7, irritability and sleep problems can be present

tx with ceftrixaone, doxy like also works

Question 9

Describe the symptoms of the late disseminated stage.

Answer 9

months after bite: intermittent attacks of large joint arthritis, encephalopathy, polyradiculophathy and fatigue

Question 10

T/F Clinical studies have found a benefit in prolonged antibiotic treatment of lyme disease.

Answer 10

false

Question 11

When and how should you test for Lyme’s?

Answer 11

can be useful in dx. esp if present in the CSF but is not present during stage 1 disease.

CDC recommends 2 step testing, ELISA first and confirmation by Western blot

Question 12

What is the treatment of choice for lyme’s?

Answer 12

stage and severity dictate choice, route and duration of antibiotics, all admin >1mo

doxycycline, alt: amoxicillin, cefuroxime
IV availble ceftriaxone

Question 13

What is the organism responsible for human granulocytic anaplasmosis and human monocytotrophic ehrlichosis along with their respective preferred cell?

Answer 13

Anaplasma phagocytophilum (Ixodes scapularis)- granulocytes

Ehrlichia chaffeenis (Lone star tick)- monocytes

Question 14

Are morulae more often seen in HME or HGA?

Answer 14

HGA 20-80% cases, rarely seen in HME

Question 15

What is the clinical presentation of HME/HGA?

Answer 15

fever headache, myalgia, and malaise
NVD, arthralgia, cough and confusion in 50%
rash maculopapular>petechial 10-40% low platelets

severe septic shok, rhabdo, ARDS, renal failure, hemorrhage, neurologic symptoms are possible; immunocompromised often get overwhelming infection

Question 16

What lab values make you think about HME/HGA?

Answer 16

low platelets
low WBC
anemia
high ALT/AST
high creatinine

Question 17

What is important to remember about the management of HME and HGA?

Answer 17

you may see moral, PCR will take weeks to come back, its important start doxycycline for suspected ehrilichosis.