Only the site where the infection has first come into contact with the skin is affected. The initial sign of about 80% of Lyme infections is an erythema migrans (EM) rash at the site of a tick bite, often near skin folds such as the armpit, groin or back of the knee, on the trunk, under clothing straps, or in childrens hair, ears or neck. Most people who get infected do not remember seeing a tick or a bite. The rash appears typically one or two weeks (range 3–32 days) after the bite and expands 2–3 cm per day up to a diameter of 5–70 cm (median 16 cm). The rash is usually circular or oval, red or bluish, and may have an elevated or darker center. In about 79% of cases in Europe but only 19% of cases in endemic areas of the U.S. the rash gradually clears from the center toward the edges, possibly forming a "bulls eye" pattern. The rash may feel warm but usually is not itchy, is rarely tender or painful and takes up to four weeks to resolve if untreated.The EM rash is often accompanied by symptoms of a viral-like illness, including fatigue, headache, body aches, fever and chills but usually not nausea or upper-respiratory problems. These symptoms may also appear without a rash or linger after the rash has disappeared.
However, unlike Lyme, in shingles these symptoms are usually followed by appearance of rashes composed of multiple small blisters along with a nerves dermatome, and shingles can also be confirmed by quick laboratory tests.Facial palsy caused by Lyme disease (LDFP) is often misdiagnosed as Bells palsy. Although Bells palsy is the most common type of one-sided facial palsy (about 70% of cases), LDFP can account for about 25% of cases of facial palsy in areas where Lyme disease is common. Compared to LDFP, Bells palsy much less frequently affects both sides of the face. Even though LDFP and Bells palsy have similar symptoms and evolve similarly if untreated, corticosteroid treatment is beneficial for Bells Palsy, while being detrimental for LDFP. Recent history of exposure to a likely tick habitat during warmer months, EM rash, viral-like symptoms such as headache and fever, and/or palsy in both sides of the face should be evaluated for the likelihood of LDFP; if it is more than minimal, empiric therapy with antibiotics should be initiated, without corticosteroids, and reevaluated upon completion of laboratory tests for Lyme disease.Unlike viral meningitis, Lyme lymphocytic meningitis tends to not cause fever, last longer, and recur. Lymphocytic meningitis is also characterized by possibly co-occurring with EM rash, facial palsy, or partial vision obstruction and having much lower percentage of polymorphonuclear leukocytes in CSF.Lyme radiculopathy affecting the limbs is often misdiagnosed as a radiculopathy caused by nerve root compression, such as sciatica.