A person with a stroke will usually have some wrinkling of their forehead.In areas where Lyme disease is common, it accounts for about 25% of cases of facial palsy. In the U.S., Lyme is most common in the New England and Mid-Atlantic states and parts of Wisconsin and Minnesota. The first sign of about 80% of Lyme infections, typically one or two weeks after a tick bite, is usually an expanding rash that may be accompanied by headaches, body aches, fatigue, or fever. In up to 10–15% of Lyme infections, facial palsy appears several weeks later, and may be the first sign of infection that is noticed as the Lyme rash typically does not itch and is not painful. The likelihood that the facial palsy is caused by Lyme disease should be estimated, based on recent history of outdoor activities in likely tick habitats during warmer months, recent history of rash or symptoms such as headache and fever, and whether the palsy affects both sides of the face (much more common in Lyme than in Bells palsy). If that likelihood is more than negligible, a serological test for Lyme disease should be performed, and if it exceeds 10%, empiric therapy with antibiotics should be initiated, without corticosteroids, and reevaluated upon completion of laboratory tests for Lyme disease. Corticosteroids have been found to harm outcomes for facial palsy caused by Lyme disease.One disease that may be difficult to exclude in the differential diagnosis is involvement of the facial nerve in infections with the herpes zoster virus.
Microvasculitis refers to a range of diseases or presentations associated with a disease, where there is inflammation of small blood vessels:

Kawasaki disease
Susac syndrome

Nerve microvasculitis
Non-systemic vasculitic neuropathy (NSVN)
Hepatitis C-related cryoglobulinemia neuropathy (CRYOVASC)
Hepatitis B-associated PAN
Diabetic lumbosacral radiculoplexus neuropathy (DLRPN)
Non-diabetic lumbosacral radiculoplexus neuropathy (LRPN)
Diabetic cervical-radiculoplexus neuropathy (DCRPN)
Diabetic Cranio-Cervico-Radiculoplexus Neuropathy
Diabetic Cervical Neuropathy


== References ==