Rosen & Barkin's 5-Minute Emergency Medicine Consult (714 page)

CODES

• 823.20 Closed fracture of shaft of tibia alone
  
• 823.22 Closed fracture of shaft of fibula with tibia
  
• 823.32 Open fracture of shaft of fibula with tibia
  

BASICS

Even in high endemic areas for tick-borne diseases, the risk of infection with a tick-borne pathogen is very low. After a tick bite, patient concerns include:

• Tick removal
  
• Local effect of the bite
  
• Possibility of acquiring a tick-borne illness:
  
  • Fear of contracting Lyme disease
    
  • Desire to be tested or treated for Lyme
    

• Specific tick-borne infections are discussed in other chapters.
  
• Tick bite can be from different species of ticks of 2 major types:
  
  • Soft ticks (
    Ornithodoros
    ):
    
    • Cause tick-borne relapsing fever
      
    • Only feed for minutes and therefore almost never provoke a visit to the ED
      
  • Hard ticks—especially
    Ixodes
    and
    Dermacentor
    :
    
    • Feed for several days to a week and therefore, more likely to be noticed by patient and lead to an ED visit
      
• Lyme disease transmission:
  
  • Species of tick, stage of development, duration of attachment, and geography may all play a role in the possibility of developing Lyme disease.
    
  • Most cases of Lyme are associated with bites from nymphal
    Ixodes scapularis
    ticks.
    
  • Most cases of Lyme are transmitted only after the tick has been attached for 24–48 hr:
    
    • Degree of engorgement is a marker for duration of attachment.
      

DIAGNOSIS

Tick is attached to skin.

• The patient usually has made the diagnosis themselves, although sometimes they mistake the tick for skin tags or other skin lesions.
  
• Ask regarding duration of tick attachment, as this may influence the decision to prescribe antibiotic prophylaxis.
  

Directly examine the skin and the tick:

• Try to identify the tick species.
  
• Estimate degree of engorgement.
  

Accurate history and physical exam searching for presence of tick

• Testing for Lyme disease is
  not
  indicated:
  
  • Such antibody testing would only reflect prior exposure to
    Borrelia burgdorferi
    
  • No treatment implications whatsoever for the current bite
    

• Testing of the tick itself is not recommended.
  
• See treatment for tick removal.
  

• Tick-borne diseases in North America:
  
  • Lyme disease
    
  • Other Lyme-like diseases such as Southern tick-associated rash illness (STARI) and
    Borrelia miyamotoi
    infection
    
  • Babesiosis
    
  • Anaplasmosis (formerly ehrlichiosis)
    
  • Rocky Mountain spotted fever (RMSF)
    
  • Relapsing fever
    
  • Tularemia
    
  • Colorado tick fever
    
  • Q-fever
    
  • Tick-borne encephalitis (Powassan fever)
    
  • Tick paralysis
    
• Additional tick-borne diseases found in Europe:
  
  • Tick-borne encephalitis
    
  • Boutonneuse fever (
    Rickettsia conorii
    )
    
  • Other spotted fever rickettsiae
    

TREATMENT

Remove tick:

• Early removal reduces the likelihood of transmission of tick-borne infections.
  

• Tick removal method:
  
  • Grasp the tick with very fine forceps, as close to the skin as possible, and gently lift up over 30–120 sec.
    
  • Most ticks will come out.
    
  • Do not to squeeze the tick, which could inject infectious materials into the patient’s skin.
    
  • If mouthparts are left in the skin, although this could lead to local infection or foreign body reaction, it has no implications for transmission of tick-borne diseases.
    
• Another described method:
  
  • Inject an intradermal wheal of lidocaine with epinephrine beneath the tick.
    
  • Tick may crawl out of its own accord.
    
• Methods
  not
  to use include:
  
  • Burning the tick with a match
    
  • Covering it with petroleum jelly or other noxious agents
    
• Lyme disease prophylaxis:
  
  • Indicated if the tick is an engorged
    I. scapularis
    nymph is found within 72 hr of the bite, or if the physician decides to prophylax
    
  • Doxycycline 200 mg for 1 dose
    
  • For children, there is no studied single-dose regimen:
    
    • Prescribe amoxicillin (25–50 mg/kg) for 10 days in divided doses.
      
    • No data support prophylactic antibiotics for other tick-borne diseases.
      

• Several studies used 10 days of amoxicillin in children for prevention of Lyme disease.
  
• No patients in the treated groups developed Lyme or seroconverted.
  
• Tick paralysis is a rare disease but usually occurs in children, especially in girls with long hair; never diagnose Guillain–Barré syndrome without doing a thorough inspection of the entire body, especially the scalp, for ticks.
  

Although there are no high quality data on antibiotic prophylaxis for Lyme disease in pregnant women, some authors recommend having a very low threshold for treating pregnant women with tick bites (using amoxicillin).

• Amoxicillin: 25–50 mg/kg in div. doses TID for 14–21 days
  
• Doxycycline: 200 mg PO for 1 dose
  

FOLLOW-UP

• Tick bite with symptoms or signs of tick paralysis or in patients who have an established tick-borne disease which is severe (e.g., hypotension or sepsis)
  
• Tick bite leading to systemic infection sufficiently severe to require admission (e.g., RMSF, anaplasmosis, babesiosis [especially in a splenectomizedpatient]).
  

All other patients, the vast majority, are safely discharged.

• Follow-up with primary care physicians if there are issues regarding local bacterial infection from the bite (cellulites) or subsequent symptoms and signs of 1 of the tick-borne infections listed above.
  
• Seek medical attention in the event of a febrile illness and to report the history of the tick bite to that physician.
  
• Patients who have been bitten by ticks should be counseled about future tick bite prevention, including potential use of DEET to the skin and permethrin-treated clothing.
  

• Early tick removal reduces the likelihood of transmission of tick-borne infections.
  
• Lyme disease prophylaxis is indicated if the tick is an engorged
  I. scapularis
  nymph.
  
• Consider babesiosis in splenectomized patients presenting with fever.
  

• Edlow JA. Introduction to tick-borne diseases.
  Emergency Medicine On-Line Textbook.
  Boston: Medical Publishing Corporation; 1997, updated 2005.
  
• Fix AD, Strickland T, Grant J. Tick bites and Lyme disease in an endemic setting: Problematic use of serologic testing and prophylactic antibiotic therapy.
  JAMA
  . 1998;279:206–210.
  
• Krause PJ, Narasimhan S, Wormser GP, et al. Human Borrelia miyamotoi infection in the United States.
  N Engl J Med.
  2013;368:291–293.
  
• Miller NJ, Rainone EE, Dyer MC, et al. Tick bite protection with permethrin-treated summer-weight clothing;
  J Med Entomol.
  2011;48(2):327–333.
  
• Nadelman RB, Nowakowski J, Fish D, et al. Prophylaxis with single-dose doxycycline for the prevention of Lyme disease after an Ixodes scapularis tick bite.
  N Engl J Med
  . 2001;345:79–84.
  
• Needham GR. Evaluation of five popular methods for tick removal.
  Pediatrics
  . 1985;75:997–1002.
  
• Sood SK, Salzman MB, Johnson BJ, et al. Duration of tick attachment as a predictor of the risk of Lyme disease in an area in which Lyme disease is endemic.
  J Infect Dis
  . 1997;175:996–999.
  
• Tibbles CD, Edlow JA. Does this patient have erythema migrans?
  JAMA
  . 2007;297:2617–2627.
  
• Tijsse-Klasen E, Jacobs JJ, Swart A, et al; Small risk of developing symptomatic tick-borne diseases following a tick bite in The Netherlands.
  Parasit Vectors.
  2011;4:17.
  
• Warshafsky S, Lee DH, Francois LK, et al. Efficacy of antibiotic prophylaxis for the prevention of Lyme disease: An updated systematic review and meta-analysis;
  J Antimicrob Chemother.
  2010;65:1137–1144.