Infectious Disease

Lyme Disease (Outpatient)

Last Updated: 08/31/2023

#Lyme Disease


  • Onset: first symptoms, progression
  • Symptoms: rash (bulls-eye, expanding), fever/chills, myalgias, arthralgias (which joints), headaches, fatigue, brain fog, neck stiffness, facial palsy, palpitations, dizziness, SOB, numbness/tingling/weakness
  • Exposures: camping or hiking in wooded, brushy, grassy areas; recent travel in last month;  other animal exposure (i.e. dogs)
  • Tick Exposure: type, color, size, attached, how long, engorged, how removed, saved
  • PMH: Prior Lyme diagnosis, other infectious diseases, immunosuppression
  • Red Flags: neurological symptoms c/w meningitis, facial droop, AMS, cardiac symptoms
  • Exam: Check for rhythm, rashes, joint swelling, strength, sensation


  • Infectious - EBV, viral meningitis, other tick-borne (anaplasmosis, babesiosis, ehrlichiosis), RMSF, syphilis, bacterial (staph/strep), post-infectious syndromes
  • Rheumatologic - RA, SLE, reactive arthritis
  • Neurologic - MS, guillain-barre, Bell’s Palsy
  • Dermatologic - cellulitis, ringworm, drug reaction, 
  • Cardiac - viral myocarditis, pericarditis, sarcoid



  • CBC, BMP, LFTs
  • Two Tier Testing: Lyme IgM and IgG EIA followed by western blot if positive; can consider serologies for other tick-borne illnesses; PCR can be sent from serum but usually sent on joint fluid or CSF
  • Joint fluid analysis with PCR and Xrays if arthritis is a prominent symptom
  • EKG if cardiac symptoms
  • LP with CSF analysis and PCR if c/f Lyme meningitis


  • Early localized (presence of EM or positive two-tier testing) - doxycycline 100mg PO BID for 10 days; alternatives include amoxicillin 500mg PO BID or cefuroxime 500mg PO BID for 14 days
  • Early Disseminated or Lyme Arthritis - doxy 100mg PO BID up to 21 days vs. inpatient admission for IV ceftriaxone 2g daily for 14+ days if symptoms are severe or disabling
  • Prophylaxis: doxycycline 200mg once if tick bite (on for 48+ hours and/or engorged) without symptoms and within 72 hours of tick removal
  • NSAIDs for arthritis pain
  • Follow up in 4-6 weeks to assess symptom resolution

Patient Guidance and Information

Lyme Diagnosis

Based on your recent visit and the tests conducted, you have been diagnosed with early Lyme disease. Lyme disease is caused by bacteria transmitted through the bite of an infected tick. Early diagnosis and treatment are crucial for a full recovery. Early treatment of Lyme disease typically results in a full recovery and we’re here to support you every step of the way.

You have been prescribed an antibiotic called *** to treat the disease. It's essential to take the medication *** and complete the entire course, even if you start feeling better.

Over-the-counter pain relievers including Tylenol and ibuprofen can help manage pain and fever

To help prevent tick exposure, when spending time outdoors, especially in wooded or grassy areas, wear long sleeves and long pants, and use tick repellents. Check your body for ticks daily and remove them promptly. Keep your yard tidy by clearing tall grasses and brush.

Please schedule a follow-up appointment in 2-4 weeks to ensure your symptoms are improving.

If you notice any worsening of symptoms or new symptoms including worsening joint pain or swelling, worsening rash, weakness, facial droop, confusion, palpitations, chest pain, or shortness of breath, please contact our office immediately.

How To Properly Remove a Tick

Start by securing a pair of fine-tipped tweezers, the ideal tool for this task. Using your fingers might squeeze the tick, potentially increasing infection risk. With the tweezers, aim to grasp the tick as close to your skin's surface as possible, targeting its head or mouthparts. It's essential to avoid the tick's body, as squeezing it can cause it to release its stomach contents into your skin.

Once you have a firm grip, pull the tick out using steady, even pressure. Ensure you pull it straight out without any twisting or jerking motions, as these can cause parts of the tick to break off and remain embedded in the skin. After the tick's removal, it's vital to clean the affected area and your hands thoroughly. You can use rubbing alcohol, an iodine scrub, or just plain soap and water.

When it comes to disposing of the tick, you have a few options. You can encase it in a sealed bag, wrap it securely with tape, or simply flush it down the toilet. If you're considering having the tick tested for potential diseases, place it in a small container with a blade of grass and consult with your healthcare provider or local health department.

Lastly, in the subsequent weeks, be vigilant and monitor for any signs of tick-borne illnesses. This could include symptoms like rashes, fevers, muscle aches, or general fatigue. If any of these symptoms manifest, it's imperative to seek medical attention immediately. Always remember: the faster you can remove a tick, the lower your risk of contracting a disease. After any outdoor activities in wooded or grassy regions, always conduct a thorough tick check for yourself, your children, and even your pets.

If You Remember Nothing Else

Lyme disease, primarily observed in the United States, Canada, and Europe, is the most prevalent tick-borne illness. Its early localized stage is often characterized by the distinctive "bull's-eye" rash known as erythema migrans (EM). However, it's crucial to note that not every patient will display this rash. The disease's progression can be broadly categorized into three phases: early localized, early disseminated, and late disease, with treatment modalities varying based on the stage and specific manifestations. For those presenting with a single EM lesion indicative of early localized Lyme, oral antibiotics such as doxycycline for a 10-day course or amoxicillin/cefuroxime for 14 days are typically effective, negating the need for IV therapy for EM alone. A significant advantage of doxycycline is its efficacy against certain co-infecting pathogens, like Anaplasma phagocytophilum. In cases where patients exhibit acute neurologic manifestations of Lyme, such as meningitis or cranial neuropathy, oral doxycycline is often the treatment of choice. In patients with cardiac involvement, IV abx like ceftriaxone may be needed. Schedule follow-up after a few weeks to ensure symptoms are resolving and to monitor for complications or progression. Always educate about tick prevention strategies.

Clinical Pearls

Tick Transmission and Characteristics:

  • Lyme is transmitted by infected Ixodes ticks, commonly Ixodes scapularis.
  • Ixodes ticks in the northeast have an estimated 20% infection rate with borellia.
  • While it's commonly believed that ticks need to be attached for at least 24 hours to transmit Lyme disease, transmission can occasionally occur in less time, especially if the tick is crushed or removed improperly. However, typically the tick needs to be attached for at least 24-48 hours for transmission.

Clinical Presentation and Symptoms:

  • While a single erythema migrans rash is pathognomonic of early Lyme disease, ocuring in 70-80% of infected patients, multiple rashes can indicate disseminated disease. The primary lesion is typically larger, with smaller secondary lesions appearing elsewhere on the body.
  • Not every patient with Lyme disease will present with the classic "bull's-eye" rash, but its presence is highly suggestive of the disease.
  • Erythema migrans isn't due to an allergy. Instead, it's because of the body's immune response to the bacteria growing in the skin layer called the dermis. After growing there, the bacteria start to spread throughout the body, leading to the next stage of the disease.
  • If EM goes unnoticed, migratory arthralgia may be the first presenting symptom which can progress to Lyme arthritis if untreated
  • Lyme arthritis, a manifestation of late disseminated Lyme disease, often presents as marked swelling and pain in large joints, especially the knee. It's distinct from the migratory musculoskeletal pains seen in the early stages.
  • Inflammation, combined with the body's immune response to the infection, can lead to muscle pain or myalgias. Additionally, the bacteria can disseminate through the bloodstream and potentially affect various tissues, leading to symptoms.

Neurological Implications and Immune Response:

  • Molecular Mimicry: There's a hypothesis that molecular mimicry plays a role in Lyme-associated Bell's palsy. Some proteins on the surface of Borrelia burgdorferi might resemble those on human cells, including neurons.
  • Bell's palsy in the context of Lyme disease is a result of a combination of direct bacterial invasion and an aggressive immune response. The confined anatomical path of the facial nerve makes it particularly susceptible to damage from inflammation
  • Lyme can cause polyneuropathy such as mononeuritis multiplex
  • Lyme carditis can cause arrhythmias (commonly AV block)
  • Post-Treatment Lyme Disease Syndrome (PTLDS): Some patients continue to experience symptoms like fatigue, pain, or joint and muscle aches even after treatment. The exact cause is unknown, and it's distinct from chronic Lyme disease.
  • Symptoms often attributed to chronic Lyme disease are non-specific and can overlap with other conditions like fibromyalgia, chronic fatigue syndrome, and depression. There's concern that some patients might be misdiagnosed with chronic Lyme disease when another condition is the actual culprit.

Diagnostic Approach:

  • While serological tests can be valuable, they might not always be positive in the early stages of Lyme disease, emphasizing the importance of clinical judgment.
  • EIA is first-tier testing - detects IgM and IgG but can yield false positives due to cross-reactivity with antibodies produced by other infections. The second tier is western blot which is more specific.
  • PCR testing is used in synovial fluid and CSF and is not sensitive in blood or urine.
  • Dark-field microscopy can be used to visualize the spirochete in early skin lesions. Culture is possible but challenging.

Treatment and Mechanism of Action:

  • Patients with acute neurologic Lyme disease, such as meningitis or cranial neuropathy, can often be treated with oral doxycycline
  • Doxycycline is a member of the tetracycline class of antibiotics. It works by inhibiting bacterial protein synthesis.
  • Doxycycline has excellent tissue penetration, making it effective against Borrelia burgdorferi in various body compartments.
  • Doxycycline is effective against other tick-borne pathogens like Anaplasma phagocytophilum and Ehrlichia spp.
  • Doxycycline is relatively contraindicated in patients less than 8 or patients who are pregnant, as it can effect growing bones/teeth
  • There used to be a Lyme disease vaccine offering waning protection, but was pulled from the market as it was not commonly used

Other Tick-Borne Diseases:

  • Anaplasmosis and Ehrlichiosis can cause leukopenia, thrombocytopenia, and elevated liver enzymes whereas babesiosis can cause hemolytic anemia since it infects red cells.

Trials and Literature

Other Resources