Tick-Borne Disease

Suspect tick-borne disease when a patient presents with a flu-like illness +/- a rash in a geographical location consistent with known tick-borne disease. Classically, patients will also present with transaminitis and thrombocytopenia.

Diagnosis can be confirmed with serology, but often, the diagnosis can be made clinically and empiric treatment may need to be initiated before serology has time to return.

Lyme Disease

• Borrelia Burgdorferi
• Tick: Ixodes scapularis
• Geography: Northeastern United States
• Symptoms
  • Stage I: Erythema migrans, nonspecific flu-like symptoms
  • Stage II: Multiple annular-shaped plaques, AV node block, radiculopathy, Bell’s palsy (may be bilateral), meningoencephalitis
  • Stage III: Weakness, encephalopathy, memory impairment, somnolence, arthritis (Chronic monoarticular arthritis with large effusion; stiffness but minimal pain)
• Diagnosis
  • 1^st: Lyme ELISA
  • 2^nd (if ELISA positive or equivocal): Western blot for IgM (if suspect < 4 weeks into infection) or IgG (if suspect > 4 weeks into infection) or both
• Treatment ₍₁₎
  • Stage I: PO Doxycycline or Amoxicillin
  • Lyme carditis: IV Ceftriaxone (unless mild first-degree block treated as an outpatient, then PO Doxycycline is acceptable)
  • Unilateral/bilateral facial nerve palsy in isolation: PO Doxycycline (or PO Amoxicillin)
  • Neuroborreliosis: PO Doxycycline, IV Ceftriaxone if severe
  • Lyme arthritis: PO Doxycycline, can use IV Ceftriaxone if PO therapy fails
• Prophylaxis (Patient must meet all 5 criteria)
  • Tick reliably identified as Ixodes scapularsi
  • Tick attachment >36 hours
  • Tick removed < 72 hours ago
  • Bite occurred in endemic area
  • No contraindications to doxycycline

Rocky Mountain Spotted Fever

• Rickettsia rickettsii
• Tick: Dermacentor sp.
• Geography: Southeast, south central United States
• Symptoms: Fever, headache, rash (blanching maculopapular rash spreads from ankles/wrists to trunk)
• Diagnosis: Serology
• Treatment: Doxycycline, can use chloramphenicol if doxycycline is contraindicated (i.e. pregnancy) ₍₂₎

Human Monocytic Ehrlichiosis

• Ehrchlichia chaffeensis
• Tick: Amblyomma americanum, Ixodes scapularis
• Geography: Southeast, south-central, mid-atlantic United States
• Symptoms: Flu-like illness, leukopenia
• Diagnosis:
  • Serology (2-4 weeks after illness)
  • PCR or buffy coat morulae (inracytoplasmic inclusions) to diagnose in acute phase ₍₃₎
• Treatment: Doxycycline

Human Granulocytic Anaplasmosis

• Anaplasma phagocytophilum
• Tick: Ixodes scapularis
• Geography: Northeast United States
• Symptoms: Flu-like illness
• Diagnosis: Serology
• Treatment: Doxycycline

Babesiosis

• Babesia microti
• Tick: Ixodes scapularis
• Geography: Northeast United States
• Symptoms: Non-specific flu-like symptoms
• Diagnosis: Serology, intracellular “maltese cross” on peripheral smear
• Treatment: Atovaquone + azithromycin OR clindamycin + quinine (if severely ill) ₍₄₎

Epidemic Typhus

• Rickettsia prowazekii
• Louse, NOT actually from a tick
• Geography: Africa, South America, Asia
• Symptoms: Fever, headache, malaise, rash (maculopapular, spreads from trunk to ankles/wrists)
• Diagnosis: Serology
• Treatment: Doxycycline, can use chloramphenicol if doxycycline is contraindicated (i.e. pregnancy) ₍₅₎

Mediterranean Spotted Fever

References:

1. Treatment for erythema migrans. (2020, November 03). Retrieved March 17, 2021, from https://www.cdc.gov/lyme/treatment/index.html
2. Edwin J. Masters, M. (2003, April 14). Rocky Mountain spotted fever. Retrieved March 17, 2021, from https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/215364
3. Ehrlichiosis / anaplasmosis. (n.d.). Retrieved March 17, 2021, from https://www.pathologyoutlines.com/topic/bonemarrowHGL.html
4. CDC – Babesiosis – resources for health professionals. (2019, October 30). Retrieved March 17, 2021, from https://www.cdc.gov/parasites/babesiosis/health_professionals/index.html
5. Akram, S. (2021, January 31). Rickettsia prowazekii. Retrieved March 17, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK448173/
6. Colomba, C., Saporito, L., Polara, V. F., Rubino, R., & Titone, L. (2006, March 22). Mediterranean spotted fever: Clinical and laboratory characteristics of 415 Sicilian children. BMC infectious diseases. Retrieved October 21, 2021, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1435909/.&nbsp;
7. Centers for Disease Control and Prevention. (2019, January 18). Imported spotted fevers. Centers for Disease Control and Prevention. Retrieved October 21, 2021, from https://www.cdc.gov/otherspottedfever/imported/index.html.&nbsp;
8. Rossio, R., Conalbi, V., Castagna, V., Recalcati, S., Torri, A., Coen, M., Cassulini, L. R., & Peyvandi, F. (2015, April 16). Mediterranean spotted fever and hearing impairment: A rare complication. International Journal of Infectious Diseases. Retrieved October 21, 2021, from https://www.sciencedirect.com/science/article/pii/S1201971215000910.&nbsp;