Acrodermatitis Chronica Atrophicans

Excerpt

Acrodermatitis chronica atrophicans (ACA) is a late and chronic manifestation of Lyme borreliosis. ACA predominantly involves the distal portions of extremities and is characterized by chronic cutaneous atrophy. Unlike other skin manifestations of Lyme disease, including erythema migrans and borrelial lymphocytoma, ACA does not spontaneously resolve. If untreated, ACA may progress from bluish-red discoloration and inflammation to chronic atrophy and fibrosis, with the late-stage being more treatment-resistant. ACA was first described in Germany in 1883 by Buchwald, and cases were later reported in North America in 1895. The diagnosis of ACA is based on clinical presentation, as well as serologic testing and histopathologic confirmation. Recognizing ACA is often challenging due to variable latency in disease onset following the primary borrelial infection and lack of symptoms leading to delay in seeking treatment.

Lyme borreliosis is the most common vector-borne disease in the northeastern United States. It is a multisystem disease caused by the spirochete Borrelia burgdorferi. It is transmitted to humans via an Ixodes tick bite. There are 3 skin manifestations of Lyme borreliosis: erythema migrans (stage 1) with a characteristic “bull’s eye rash,” which, if untreated, can be followed by early disseminated infection, borrelial lymphocytoma (stage 2) along with neurologic and cardiac abnormalities, and late infection, especially arthritis in North America or ACA (stage 3) in Europe. ACA is the most common late and chronic manifestation of Lyme borreliosis. Approximately 20% of patients with ACA have a history of spontaneously healed EM, usually on an extremity where the ACA lesion developed 6 months to 8 years later.