Lyme disease is an infection caused by Borrelia burgdorferi, a type of bacterium called a spirochete that is carried by deer ticks. An infected tick can transmit the spirochete to the humans and animals that it bites. The infected tick normally cannot begin transmitting the spirochete until it has been attached to the host about 36-48 hours. Untreated, the bacterium travels through the bloodstream, establishes itself in various body tissues, and can cause a number of symptoms.
Microscopy of the spirochete Borrelia burgdorferi
Lyme disease manifests itself as a multisystem inflammatory disease that affects the skin in the early, localized stage, and spreads to the joints, nervous system and sometimes to other organs in later stages. If diagnosed early and treated with an antibiotic, the disease is readily cured. In later stages the disease can also be treated.
Lyme is more frequent in the northeast and upper mid-west of the US. It is also prevalent in northern California and Oregon coast. In these regions is there is large numbers of the deer tick's preferred hosts, white-footed mice and deer, and they are in closer proximity to humans. Lyme disease was first described in the US in 1975 after an outbreak of juvenile arthritis in the town of Lyme, Connecticut. However, it was already known and described in Europe by other terms, one of them Bannwarth’s syndrome
Symptoms of Lyme Disease
The typical rash of Lyme expands in size over a few days, with a red spot that may clear around the center; this is the Bull’s eye rash, called erythema migrans. It rarely expands beyond 3-6 inches at the site of the tick bite. Multiple skin lesions can be present. Onset is 3 to 30 days after the bite and persists for 2 to 5 weeks. It is rarely itchy and is never painful with blisters. The tick will often have migrated to body creases such as back of the knee, groin, armpit, nape of the neck. These are the more frequent locations of the rash. The tick may never be seen and a rash may never appear in some patients with Lyme disease.
Lyme rash of erythema migrans
Early symptoms resemble the flu and may include:
- Bull’s eye rash
- Enlarged lymph nodes
- Diffuse body itching
- Malaise, fatigue, a feeling of being ill
- Fainting spells
- Muscle and joint aches
- Stiff neck
The early symptoms may be transient, or may recur with new and different ones. With later stage Lyme disease there may be spread to specific organs of brain, peripheral nerves, joints and heart. Symptoms may now include:
- Joint pain and swelling, sometimes migrating
- Muscle weakness
- Numbness and tingling
- Radiating arm or leg pain
- Facial weakness (Bell’s palsy)
- Irregular heart rate (palpitations)
- Severe headaches and neck pain
- Speech problems
- Imbalance when walking
- Strange behavior
- Memory problems
Involvement of the nervous system occurs in 10-15% of patients infected with Lyme disease. Yet, there remains much controversy surrounding neurological Lyme. It is very common for the patients to develop nonspecific symptoms, including fatigue, mental slowing, headaches, word-finding difficulties and memory loss. But, these symptoms are also present in most other infectious and inflammatory illnesses. Intermittent intellectual and cognitive problems are normal in ALL healthy people. Have a martini and your short-term memory will be impaired. Pathological cognitive issues are related to numerous medical conditions that far extend beyond the field of neurology. The person with pneumonia cannot think clearly, the patient with heart attack has word-finding difficulties.
After the very early period of exposure lasting a few weeks, it is misleading that some doctors will claim that Lyme disease is a clinical diagnosis, and it is misleading to derive a diagnosis from a check list of symptoms.
Involvement of the nervous system is a later manifestation of Lyme. Facial palsy and meningitis with inflammation of the lining around the brain occur rather early during this “late” stage, perhaps weeks to a few months after exposure. Other neurological conditions are later, slower, protracted and indolent, occurring months to a few years after the tick bite. Peripheral neuropathies may cause numbness, tingling or weakness in one or several limbs. Sometimes, a painful pattern can imitate a pinched nerve of the spine at the neck or lower back.
The symptoms meningitis of Lyme are similar to that of a viral infection with headache, neck stiffness, light sensitivity; sometimes fever is not present. Many patients with facial palsy have this inflammation of the cerebrospinal fluid around the brain. More extensive involvement of brain and spinal cord (encephalomyelitis) is increasingly rare. Complaints of fatigue, psychomotor retardation, intellectual slowing, word-finding difficulties, impaired memory have been used to support a diagnosis of Lyme encephalopathy. Such a presentation is rarely due to Lyme disease and might be related to other neurologic or non-neurologic condition. The proper diagnostic tests should be done for these patients.
The condition of “Chronic Lyme Disease” is now less controversial. The term was used for patient with some or many of the symptoms described above with or without past documented Lyme disease. Patients were treated for many months, even years with antibiotics. The cause of persistent, nonspecific symptoms after treatment of Lyme disease still remains an area of uncertainty. The American Academy of Neurology, 2007, the International Lyme Disease Group, 2007, and the IDSA guidelines, 2006 have concluded that after appropriate treatment there is not a condition of chronic persistent infection with Lyme spirochete underlying persisting subjective symptoms and that chronic use of antibiotics for “chronic Lyme disease” is not justified.
Diagnosis of Lyme Disease
Diagnosis of early Lyme disease is clinical, meaning that it is based on the patient’s history and physical findings, since blood tests are not reliable initially. History should include some likelihood of an exposure to tick bite. If possible, bring the tick to the doctor and make appointment while the rash is still present.
Four to 6 weeks after the tick bite, blood testing is highly sensitive and specific for the diagnosis of Lyme disease. A two-stage approach with serological blood testing is recommended by the Center for Disease Control. If an initial and highly sensitive screening test is positive, a second test is done that is highly specific. The screening test is either ELISA (enzyme-linked immunosorbent assay), or IFA (immunofluorescent assay), or, more recently, Lyme C6 Peptide. If one of these tests is negative, the blood sample needs no further testing, since the patient does not have Lyme disease.
If the initial testing is positive, beware, and do NOT diagnose Lyme disease. Unfortunately, many patients have remained convinced of persisting (or recurring) disease with such result. Very often, it is a false positive result of no clinical significance, but it does require the second stage testing with a Western Blot for two types of antibodies, IgG and IgM.
Positive IgG suggests previous exposure to Lyme, but does not prove recent or acute illness; this test too can sometimes be misleading due to false positive findings. A positive Lyme C6 Peptide is a useful confirmatory test here, since is appears to be more accurate with fewer false positive occurrences. Positive IgM suggests acute Lyme disease. A few months after the acute illness, the pattern of the Western Blot, “converts” to IgG positivity with resolution of the abnormality on the IgM. Rarely, have we seen persisting IgM positivity. The abnormal IgG response may persist for years, to the dismay and confusion of patients (and physicians?).
Lumbar puncture with spinal fluid analysis is done on some, but not all patients with suspected neurological Lyme, or neuroborreliosis. If blood testing is negative for Lyme, lumbar puncture should not be done. Symptoms of headache, neck stiffness, facial weakness and/or numbness or tingling of limbs usually do require this test. It is not useful for evaluation of the peripheral nervous system. Even in the absence of Lyme disease of the brain, antibodies to Lyme can migrate from blood to brain, without spreading infection. Thus, “false-positive” results may occur on analysis of the cerebrospinal fluid (CSF). A criteria for diagnosis of CNS Lyme based on excess antibodies in spinal fluid compared to blood has resulted in underestimating the occurrence of the illness. Thus, the sensitivity of the test remains unclear, but it is very useful for the clinician in the overall context of the particular patient.
Polymerase chain reaction (PCR) was used extensively in the 1990’s but had too low sensitivity. It is now rarely done.
MRI of the brain is rarely useful for diagnosis of CNS Lyme, although the study sometimes may be needed to “rule-out” other conditions. SPECT scan (single photon emission computed tomographic) have been overused and misinterpreted in the past. Electrodiagnostic studies are done in patients with symptoms of the peripheral nervous system.
Lyme disease, including facial weakness, is treated with an oral antibiotic such as doxycyline, amoxicillin or ceftin. If severe neurological or cardiac symptoms are present, use of intravenous antibiotic is recommended. Optimal duration of treatment is still debated, but use of IV medication for more then 6 weeks is not support by scientific evidence and is often associated with significant adverse side effects.
You are at higher risk if you garden, hike, camp, hunt, work outdoors or otherwise spend time in woods, tall grass, brush or overgrown fields. Avoid, if possible soil, leaf litter edges of woodlands, areas around stone walls. If exposed to such fields, examine yourself at least daily and remove any tick before engorged and swollen with blood.
Learn to distinguish between different ticks. Deer ticks and Western black-legged ticks transmit Lyme disease. Dog ticks and Lone Star ticks do not. May through September is the season for acute Lyme.
A single dose of doxycycline may be taken as prophylactic treatment for Lyme disease after tick bite, provided the tick is black-legged or deer tick AND it has been attached for at least 36 hours and medicine is taken within 72 hours of the time that the tick is removed. Doxycycline is contraindicated in pregnancy and children less than 8 years old. Amoxacillin cannot be used for prophylaxis.
Personal protection remains the most reliable method of tick-borne disease prevention. Use protective clothing and shoes. Use insect repellant containing DEET (diethyl-meta-toluamide) on skin or clothes. Do not sit directly on the ground or on stone walls. Keep long hair tied back. Check entire body for ticks at end of day. A shower may remove crawling ticks. Remove embedded tick with pair of pointed tweezers by pulling out at head or mouthparts, not the body; clean site and keep tick in a vial. Not all deer ticks are infected. An infected tick begins to transmit Lyme disease 36 – 48 hours after attachment.
Embedded deer tick with early rash.
(Unusual photo: no Lyme rash appear before 3 days of attachment, but tick does not feed more than two days....)
Modified with information from:
Illinois Department of Public Health
American Lyme Disease Foundation
Center for Disease Control: http://www.cdc.gov/lyme/