Acrodermatitis chronicum atrophicans
Acrodermatitis chronicum atrophicans (ACA) is a skin rash indicative of the late stage of European Lyme disease. It can be caused by both Borrelia afzelii and Borrelia garinii and is most evident on the extremities.
It has an early inflammatory stage with localized redness or bluish-red discoloration and swelling of the skin.
Several months or years later it ends in a chronic atrophic phase. As a result of sclerosis, fibrosis and atrophy the skin becomes wrinkled and thin. There is a loss of sweat glands and hair. Blood vessels may become dilated.
ACA can cause problems with the peripheral nervous system and cause allodynia which is the experience of pain with non-painful stimuli. Other patients can have persistent or intermittent pain in their extremities which are peripheral neuropathies.
Treatment and outcome
Treatment includes antibiotics such as doxycycline, amoxicilline, cefuroxime axetil or intravenous ceftriaxone for up to four weeks in the acute phase. In individual cases longer antibiotic therapy may be necessary.
In the early inflammatory phase the skin changes are reversible. In the chronic atrophic phase skin changes are often irreversible.