Lyme disease

Background

• Tick Borne
• Endemic Areas: NE, E US Coasts
• Caused by spirochete Borrelia burgdorferi
• Peak in May to Aug
• Stages: Early localized infection, early disseminated, and late disseminated

Clinical Features

• Early Localized Infection (7-14d)
  • Erythema Migrans: At bite site beginning w/ red macule that expands outward
  • Fatigue, low grade fever, migrating arthralgia, lymphadenopathy, headache, N/V, abd pain
• Early Disseminated Infection (Days to weeks)
  • Skin-mult annular lesions sparing palm/soles
  • Nervous System-fluctuating meningoencephalitis, HA, N/V, CN palsies (ie 7th-can be bilateral) peripheral neuropathy, radiculopathy
  • Cardiovascular: AV blocks, RBBB, dysrhythmias, LV dysfunction
  • Eye: Conjunctivitis, keratitis, retinal detachment, optic neuritis
• Late Disseminated Infection (Months to Years)
  • Arthritis: Monarticular/oligoarticular asymmetric arthritis (large joints-commonly knee)
    • Brief episodes separated with complete remission
    • Migratory pattern may occur
  • Nervous System: Subtle encephalopathy, fatigue, polyneuropathy

Diagnosis

• ELISA if positive obtain confirmatory Western blot
• PCR
• Cultures, serologies
• LP with lymphocytic pleocytosis, elevated protein, normal glucose, + spirochete antibody, paired serum/CSF serologic tests,PCR
• Arthrocentesis, serologic testing of fluid

DDx

• Enterovirus
• Hepatitis
• Mononucleosis
• Connective tissue disease
• Erythema Multiforme
• CAD
• Acute rheumatic fever
• Aseptic menintgitis
• HSV encephalitis
• Bell's Palsy
• MS
• Guillain-Barre
• Cerebral Vascultitis
• Juvenile rheumatoid arthritis

Treatment

Early Localized Infection

• Treat before serologic testing if endemic area if + erythema migrans rash
  • Doxycycline 100 mg PO BID x 14-21 days
    • Also treats human granulocytic ehrlichiosis
  • Amoxicillin 500 mg PO TID x 14-21 days
    • Preferred in pregnant, lactating, children <8
  • Cefuroxime axetil 500 mg PO BID x 14-21 days
  • Macrolides-not first line
• Jarisch-Herxheimer like reaction can occur in first 24 hrs of treatment (fevers, chills, myalgia, tachycardia)

Early Disemminated

• Doxycycline (see above dosing)

• Amoxicillin (See above dosing)

Lyme Meningitis

• Ceftriaxone 2g IVq12h x 14-28 days
  • Doxycycline 200-400 mg/d divided into two doses q day x 10-28 days
  • Penicillin G, Cefotaxime

Cardiac Disease

• Mild (1st degree AV with PR <0.3 sec)
  • Doxycycline/Amoxicillin PO
• Severe (HIgh-degree AV block)
  • Ceftriaxone/Pen G IV

Arthritis

• Doxycycline, Amoxicillin PO, as effective as parenteral
• Ceftriaxone/Pen G IV

Prophylaxis

• Adult: Doxycycline 200 mg PO x1
• Child >8: 4 mg/kg up to 200 mg PO x1
• Give if all of the following are met:
  • Tick is adult/nymphal I. scapularis
  • Tick was attached >36 hours based on degree of engorgement or exposure time
  • Prophylaxis can be given within 72 hrs after time tick was removed
  • Local rate of infection in ticks >20%
  • Doxycycline is not contraindicated
• Old vaccine has little to no efficacy after 1 year

Dispo

• Outpatient
  • Early Disease
  • Late Disease: If chronic neurologic/arthritic manifestations may be able to manage as outpt
  • F/u with PMD, rheum, ID
    
• Admission
  • Lyme carditis-cardiac monitoring
  • Prominent neurologic symptoms for IV Abx and further care

Source

Harwood and Nuss