What is Lyme disease?

Lyme disease is a multi-system infectious condition that frequently causes fatigue and headache and can progress to arthritis, memory problems and other complications. It is the leading tick-borne disease in the United States.

Lyme disease occurs most often in rural and suburban areas in the U.S. Northeast, mid-Atlantic region and upper Midwest. It also affects parts of Canada, Europe, Australia and Asia, where it is often called Lyme borreliosis. Lyme disease was first identified in the United States in 1975 near Lyme, Conn. However, its existence has been documented in Europe for almost a century.

Lyme disease progresses in three stages: early localized, early disseminated and late Lyme disease. As the bacteria spread, symptoms of fatigue and headache may appear.

If the disease progresses to late Lyme disease, arthritic symptoms can appear, along with cognitive difficulties and skin puffiness. These may take months or years to appear.

When treated, most people recover quickly and experience very few complications from Lyme disease. A small percentage of patients recover slowly or do not fully recover from symptoms if they are not treated in a timely manner.

Bacteria called Borrelia burgdorferi cause Lyme disease. These bacteria are transmitted to humans through bites from infected ixodes ticks, which may be referred to as deer ticks or black-legged ticks in the eastern United States and western black-legged ticks in the western United States. These tiny ticks are smaller than those typically found on a dog and are difficult to spot.

The disease spreads when an infected tick takes a blood meal, passing infectious bacteria to an animal (usually a deer or mouse, sometimes another mammal or a bird) and making them a host for the disease. Other ticks feeding on the infected host animal contract the disease themselves, then pass it to more deer or mice. Ticks await new hosts by hiding within areas dense with grass or shrubs, most notably those along boundaries between residential properties and surrounding forest land and along deer paths. A tick senses carbon dioxide exhaled by humans or animals as they pass. The tick attaches itself to body parts that happen to rub up against it.

The tick must remain affixed to human skin for at least 36 hours for humans to become infected. Furthermore, the tick can take as long as 24 hours from the time it attaches itself before feeding may even begin. As a result, Lyme disease affects very few people who are bitten, even in areas with high populations of infected ticks.

Lyme disease is most common in the summer and early fall when biting ticks are young, small and difficult to detect. Less frequent are cases in the late fall, early winter and early spring when biting ticks are fully developed and easier to spot.

The ticks that transmit Lyme disease can also spread two other conditions: human granulocytic anaplasmosis (HGA) and babesiosis. Infection with HGA (formerly known as ehrlichiosis) may be widespread but unrecognized, according to the CDC. Symptoms include malaise, fever, muscle pain (myalgia) and headache. In rare cases death has resulted.

Babesiosis is an infection of the red blood cells by a tiny parasitic protozoan. It can cause anemia and a malaria-like illness marked by fever, chills, excessive perspiration, muscle pain, headache and malaise. Patients infected with both diseases are more likely than those afflicted only with Lyme disease to experience symptoms including fatigue, anorexia (loss of appetite), unstable emotions, nausea, conjunctivitis (an inflammation of the eye) and splenomegaly (enlarged spleen), according to the National Institutes of Health (NIH). In rare cases death has resulted. Babesiosis may affect about 10 percent of Lyme disease patients in southern New England, according to the NIH.

As with Lyme disease, HGA and babesiosis are treated with antibiotics and respond best to early treatment.

How is it diagnosed?

Diagnosis of Lyme disease begins with a medical history, including questions about exposure to deer ticks, and a physical examination, including inspection of the skin for the red rash known as erythema migrans (EM).

However, this disease is often difficult to diagnose. Its symptoms can be confused with indicators of other conditions, such as fibromyalgia or chronic fatigue syndrome. Also, some people in an endemic (infected) area may have the disease without the rash or other signs and symptoms. Usually the patient has a lot of testing before Lyme disease is diagnosed.

Consequently, several tests may be used in diagnosis, such as:

The presence of erythema migrans is important in diagnosis of Lyme disease. Unlike many other types of infections, blood tests for Lyme disease are sometimes falsely positive (inaccurately indicating the disease where it is not present) when there are only nonspecific symptoms. In an attempt to avoid unnecessary treatment, blood tests are rarely performed when EM is not present.

How is Lyme disease treated?

Any stage of Lyme disease is treatable in almost all circumstances. Most people experience a full, quick recovery with minor complications. However, some people recover slowly if diagnosed when the disease is in its later stages. Left untreated, Lyme disease can be permanently disabling or even fatal in some instances.

Lyme disease can be treated most effectively with minimal risk for further complications if diagnosed in its early stages. Antibiotics stop the disease from progressing and may lessen the severity of symptoms. Patients experiencing early-phase Lyme disease receive oral antibiotics daily for 10 to 14 days. In certain cases oral antibiotics may produce side effects such as upset stomach, diarrhea or allergic reaction.

Arthritis that is caused by Lyme disease (infectious arthritis) is also treated with antibiotic therapy. In some cases when arthritis lingers after antibiotic treatment, drugs that suppress inflammation may be required.

Late-stage, ongoing or serious Lyme disease usually requires intravenous (I.V.) antibiotics (e.g., ceftriaxone, cefotaxime). Through a catheter placed in a vein, antibiotics are administered daily for about two to four weeks. Side effects of I.V. antibiotics vary and may include a decrease in white blood cells, abdominal pain, diarrhea, colitis (inflammation of the colon) or allergic reaction.

People with Lyme disease may also need anti-inflammatory medication such as ibuprofen to reduce inflammation and pain and to improve function.

Patients receiving antibiotic treatment for Lyme disease sometimes experience a short–term worsening of symptoms (Jarisch-Herxheimer reaction) caused by dying bacteria. It typically begins about 24 hours after antibiotic treatment has begun and lasts about the same amount of time before ending. Antibiotics should continue to be administered as originally intended if a Jarisch-Herxheimer reaction occurs.

In cases where antibiotic treatment shows no effect in an individual considered to have Lyme disease, re-evaluation by a physician is typically necessary. The most common reason for this occurrence is misdiagnosis, with symptoms attributed to Lyme disease actually being caused by another condition.

Patients are urged not to try unproven, unapproved and possibly dangerous substances that are sometimes touted as a cure for Lyme disease. The U.S. Food and Drug Administration in 2006 issued a warning against an injected compound called bismacine or chromacine. It can cause complications including kidney failure and cardiovascular collapse and is blamed for at least one death.

The Infectious Diseases Society of America (IDSA) updated its guidelines on Lyme disease in 2006. Its general recommendations include:

• Not routinely using antibiotics after a tick bite
• Offering one oral dose of the antibiotic doxycycline only in specific circumstances for people who were bitten by a tick but do not show symptoms of the disease
• Treating early Lyme disease with oral doxycycline, amoxicillin or cefuroxime axetil
• Avoiding doxycycline in pregnant patients
• Treating early neurologic Lyme disease (involving meningitis or radiculopathy) with intravenous ceftriaxone
• Treating late neurologic Lyme disease with intravenous ceftriaxone or, as an alternative, intravenous cefotaxime or penicillin G
• Not using certain treatments described as lacking in scientific evidence, such as hyperbaric (high-pressure) oxygen, ozone, fever therapy, certain dietary supplements, long-term use of antibiotics, combinations of antimicrobials, pulsed dosing, first-generation cephalosporins, fluoroquinolones, carbapenems, vancomycin, metronidazole, tinidazole, amantadine, ketolides, isoniazid, trimethoprim-sulfamethoxazole, fluconazole or benzathine penicillin G
• Using antimicrobials to treat the other diseases spread by the Lyme disease tick: human granulocytic anaplasmosis (HGA) and babesiosis. Doxycycline is suggested for all symptomatic patients suspected of having HGA. A combination of atovaquone and azithromycin, or clindamycin and quinine, is suggested for patients with active babesiosis.

The guidelines emphasize that they do not apply in all cases and are not meant to replace a physician's recommendations. They also stress the importance of preventing Lyme disease by reducing exposure to ticks.

The IDSA's recommendations have sparked some controversy, including criticism from the Lyme Disease Association that the opposition to long-term antibiotic therapy was depriving chronic Lyme patients of beneficial treatment. The International Lyme and Associated Disease Society (ILADS) recommends that antibiotic treatment be guided by the patient's response rather than preset limits, and says that for persistent Lyme disease a patient may need to be treated for months after symptoms have disappeared.

Medications

What might complicate it?

The recurrence of infectious arthritis, even with antibiotic therapy, or the development of chronic arthritis in untreated infections may complicate the disease. Chronic arthritis may lead to stiffening of the joints and movement limitations. Individuals who went without antibiotic treatment for a longer period of time have more chronic joint symptoms and memory impairment. Cardiac complications might include arrhythmias or severe heart block. Serious neurologic disorders (such as meningitis or encephalitis, and demyelinating disorders similar to multiple sclerosis) have been associated with Lyme disease, and can lead to permanent impairment or death.

Alternatives

Other bacterial infections may invade a joint and cause infectious arthritis similar to that found in early Lyme disease. Other viral, bacterial and fungal causes of meningitis or encephalitis may give symptoms similar to neurological complications of Lyme disease.

Appropriate specialists

Infectious disease specialist, orthopedic surgeon, neurologist and cardiologist.

Last updated 13 July 2015