[Clinical aspects and etiology of acrodermatitis chronica atrophicans].

We followed up nine patients with acrodermatitis chronica atrophicans (ACA) for an average of 2 years (6-44 months). Extradermal symptoms were observed in five patients, three of whom developed systemic signs such as fatigue or general sensitivity to cold; three suffered from cardiac symptoms; and two had joint and/or nervous system involvement. In one patient, erythema migrans and oligoarthralgia preceded the ACA. In most patients, the laboratory tests showed changes often seen in inflammatory diseases; we found an elevation of IgA, IgG and/or IgM in five patients. Using an indirect immunofluorescence test with Ixodes dammini spirochetes as antigen, the patients had more or less elevated IgG antibody titers and insignificant IgM antibody titers; similar results were obtained in some patients when an Ixodes ricinus spirochete isolated in the area of Munich was used as antigen. We believe that ACA is a chronic spirochetosis with manifestations present in the skin, joints, nervous system, and presumably in the heart.