In November 1983 a woman born in 1902 was found to have thrombocytopenic purpura with a platelet count of 14,000/microliter. Examination of the sternal marrow resulted in a suspected diagnosis of Werlhof’s
disease. Platelet counts dropped at times to below 7,000/microliter during immunosuppressive treatment with corticosteroids and azathioprine of three months’ duration. When this treatment was discontinued spontaneous remission occurred until July 1984. Acrodermatitis chronica atrophicans was diagnosed in August 1987. The IgG antibody titre against Borrelia burgdorferi of 1:2,000 in whole blood and the late manifestation of
Lyme disease (chronic acrodermatitis atrophicans) suggest a causal relationship with the previous thrombocytopenic purpura.