Lyme disease in Adult
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Synopsis

Early disseminated disease occurs within weeks as the spirochete disseminates to the nervous system, heart, joints, and other organs. At this time, patients may develop multiple widespread skin lesions of disseminated EM along with acute neurologic abnormalities, atrioventricular (AV) block, or myocarditis. Months later, untreated patients may progress to late stage disease that manifests with arthritis, mild encephalopathy, neuropathies, and, in Europe, acrodermatitis chronica atrophicans.
In the United States, Lyme disease is primarily seen in New England, the Midwest states, and the west coast. It is endemic to most of Europe. The ticks that transmit Lyme disease are of the genus Ixodes (eg, Ixodes scapularis, the blacklegged tick or deer tick). Mice and deer are the major animal reservoirs. Transmission occurs most commonly in the spring and summer months. Increased risk of infection is strongly linked to the amount of time spent in wooded or rural areas.
Lyme disease has been rarely reported in China, Japan, and Russia. Although Lyme disease is not considered endemic to countries in Africa, there have been few cases of infection reported.
Rarely, coinfection with Babesia microti has been documented.
Lyme disease is subdivided clinically into 3 phases:
- Early localized disease
- Early disseminated disease
- Late disease
Systemic symptoms are seen in approximately half of patients with early localized or early disseminated disease. These symptoms are described as flu-like and include a combination of fatigue, headache, neck stiffness, myalgias / arthralgias, lymphadenopathy, or fever. With B mayonii infection, which at present seems to be limited to the upper midwestern United States, nausea and vomiting may also occur, and the rash may be more diffuse.
Early Localized (days to weeks following tick bite):
- EM at the site of the tick bite develops in approximately 60%-90% of patients.
- In Europe, early lesions sometimes present as Borrelia lymphocytomas.
- There may or may not be systemic symptoms.
- False negative serological testing is common.
- Multiple widespread skin lesions represent dissemination of the infection with or without systemic symptoms.
- Approximately 10%-15% of patients develop neurologic features including meningitis and cranial or peripheral neuropathies. Facial nerve palsy (Bell palsy) is the most commonly associated cranial nerve neuropathy. Borrelial meningoradiculitis, often called Bannwarth syndrome, is a rare manifestation (especially in Europe) associated with painful myeloradiculitis, lymphocytic meningitis, and cranial nerve palsies as well as motor weakness, headache, sleep disturbances, and sometimes gastrointestinal symptoms.
- Approximately 5% of patients may experience cardiac manifestations, usually AV block or myocarditis.
- Serological testing is usually positive, but false negatives may still occur.
Untreated cases can also lead to:
- Chronic arthritis (typically knees)
- Mild encephalopathy with subtle cognitive deficits
- Axonal polyneuropathies
- Acrodermatitis chronicum atrophicans (Europe)
- Serological testing is virtually always positive.
A small percentage of patients diagnosed with Lyme disease who received adequate therapeutic treatment have reported ongoing nonspecific symptoms that typically improve within one year. Persistent infections in humans despite treatment have not been reliably demonstrated. Despite extensive study of this entity, numerous expert reviews have concluded that no consistent, reproducible syndrome or evidence of persistent infection resulting in these vague symptoms exists. However, primary reinfection has been demonstrated in individuals in endemic areas.
Related topic: Lyme keratitis
Codes
ICD10CM:A69.20 – Lyme disease, unspecified
SNOMEDCT:
23502006 – Lyme disease
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Differential Diagnosis & Pitfalls
Early:- Southern tick-associated rash illness (STARI) clinically presents with EM but is transmitted by the lone star tick Amblyomma americanum.
- Erythema annulare centrifugum has a fine collarette of scaling inside the border of the lesion (trailing scale).
- Arthropod bite reaction develops rapidly after bite and does not demonstrate a flat, slowly expanding lesion.
- Arthropod bite granuloma can be firm and typically does not expand.
- Infection with Borrelia miyamotoi
- Fixed drug reactions do not expand and are often < 5 cm.
- Tinea corporis – Associated lesions have overlying scale.
- Contact dermatitis may develop vesicles or bullae within lesions, but it is typically more symptomatic and less symmetric.
- Erysipelas / cellulitis has a more rapid onset with tender, streaking, or raised erythema as it expands from the site of initial infection.
Multiple Lesions
- Erythema multiforme lesions are more numerous, smaller, duskier, and are symmetrically distributed, favoring the hands, face, and forearms. Oral mucositis or crusting may be present. It is associated with concomitant herpes or mycoplasma infection.
- Secondary syphilis can have a characteristic "rust" color and overlying scale.
- Pityriasis rosea presents with a herald patch and thin, raised, scaly plaques in characteristic "fir tree" distribution over the trunk.
- Urticarial lesions are edematous, pruritic, and typically resolve within 24 hours.
- Pseudolymphoma (lymphocytoma) may result from a number of stimuli, including arthropod bites, that cause an inflammatory reaction pattern in the skin leading to the formation of nodular lesions clinically and histologically resembling cutaneous lymphoma. Borrelia lymphocytoma is a subset of pseudolymphomas.
- Nodular scabies is more common in the groin and extremely pruritic.
- Carcinoma erysipeloides presents as an ill-defined, jagged, light pink plaque typically overlying the breast or upper chest.
- Granuloma faciale is more raised, edematous, and restricted to the face.
- Circulatory insufficiency with dependent rubor.
- Eosinophilic fasciitis is rare but favors the distal extremities and produces woody induration of the skin but typically stops near the wrist or metacarpal joints and does not involve the distal hands or fingers.
- Dermatomyositis has a characteristic heliotrope rash; atrophic dermal papules of dermatomyositis (formerly called Gottron papules) over dorsal distal interphalangeal (DIP), proximal interphalangeal (PIP), metacarpophalangeal (MCP) joints; and a "shawl" sign.
- Morphea
- Atrophoderma of Pasini and Pierini
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Last Reviewed:06/25/2022
Last Updated:07/21/2020
Last Updated:07/21/2020


Overview
Lyme disease is the result of infection with the bacteria Borrelia burgdorferi. The disease is transmitted by infected ticks that also feed on mice and deer. The tick can be found attached to the skin in many cases. Most cases of Lyme disease occur in the spring and summer months.Lyme disease, in most cases, can be eliminated with antibiotics, especially if treatment is started when symptoms are first noted.
Lyme disease is divided into 3 phases:
Early localized:
Symptoms start a few days to a month after a tick bite. The classic "bull's eye" lesion does not need to develop for a diagnosis of Lyme disease. If left untreated, the disease can spread to the lymph nodes.
Early disseminated:
Multiple skin lesions are seen, along with flu-like symptoms and head, neck and joint pain. There may also be heart or nerve symptoms as well as arthritis, which can develop over a few months to up to 2 years after the initial infection.
Late:
The heart, joints, and nervous system can be affected. Symptoms can develop over a few months to years after the initial infection and may be difficult to treat.
Who’s At Risk
Lyme disease is transmitted by infected ticks and cannot be "caught" from an infected person. Individuals who spend a lot of time in or near wooded areas are at a higher risk for contracting Lyme disease. Lyme disease is reported most often in the Northeastern US from Maine to Maryland, in the Midwest in Minnesota and Wisconsin, and in the West in Oregon and Northern California. It has also been reported in China, Europe, Japan, Australia, and the parts of the former Soviet Union.Signs & Symptoms
Sometimes the tick can be found attached to the skin. Bite marks may not necessarily be visible.Erythema migrans, the classic unraised red "bull's-eye" lesion on the skin, will appear days to weeks after the bite. However, about 25% of affected people never get this lesion. Some may complain of flu-like symptoms, including fever; head, neck, and joint pain; and generalized muscle pain. The lesion will resolve without treatment in about a month.
Weeks to months later the bacterium can affect the joints, heart, and nervous system.
The late phase of Lyme disease can also affect the joints, heart, and nervous system. In the heart, there can be an abnormal heart rhythm. The face can become paralyzed (facial muscle paralysis), and you can have confusion and abnormal sensations of the skin such as numbness, tingling, a prickling sensation, or pain. There can be inflammation in the joints, or arthritis, beginning with swelling, stiffness, and pain, commonly affecting the knees.
Self-Care Guidelines
If you suspect you have had a tick bite and may have contracted Lyme disease, call your doctor. If you have found a tick on your skin and removed it, you may want to save the tick in a small container of alcohol so that it can be used for identification.Ticks begin transmitting Lyme disease about 24–48 hours after attaching to the host. You can reduce your chances of getting Lyme disease by removing the tick within 48 hours.
To remove the tick, you will need tweezers and isopropyl alcohol.
- Sterilize the tweezers with alcohol, and make sure to wash your hands. You should not clean or disturb the skin near the tick.
- Grasp the part of the tick that is embedded in the skin with the tweezers, not the body where you may see tiny legs.
- The tick will likely be firmly embedded. Pull it outward in one motion. Do not twist or jerk the tweezers. Do not apply anything to the tick that you think may help it come out smoothly as this may result in a part of the tick being left in the skin.
- Clean the bite wound with alcohol. If you are not sure if the entire tick has been removed, see your doctor.
When to Seek Medical Care
It is probably best to call your doctor for further guidance if you think you have been bitten by a tick. If a rash or other early symptoms of Lyme disease develop, see a physician immediately.Treatments
Lyme disease can be treated and cured with one of several oral antibiotics for 3-4 weeks. The skin rash will go away within a few days of beginning treatment, but other symptoms may persist for up to a few weeks. In severe cases of Lyme disease where the nervous system is involved, the antibiotic may need to be given intravenously. In late stage Lyme disease, symptoms may not go away completely, but should improve.References
Bolognia, Jean L., ed. Dermatology, pp. 1138-1139. New York: Mosby, 2003.
Wolff, Klaus, ed. Fitzpatrick's Dermatology in General Medicine. 7th ed., pp. 1797-1806. New York: McGraw-Hill, 2008.
Lyme disease in Adult
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