Acrodermatitis chronica atrophicans Herxheimer can often mimic a peripheral vascular disorder.

During the past few years five patients have been referred to the angiology section at Danderyd Hospital under the diagnosis of chronic venous insufficiency but who were instead suffering from acrodermatitis chronica atrophicans (ACA). The typical case of ACA starts with a limited inflammatory lesion, which is gradually replaced by atrophy and the skin shows a bluish, red discoloration. Late changes may be subluxation of joints in hands or feet and periosteal thickening. Capillary microscopy often reveals a clear picture of atrophy and a prominent, dilated subpapillary venular plexus. If localized to the leg the blood flow of the foot and lower leg may be increased, skin temperature elevated and venous capacity and return augmented. All these variables can consequently mimic venous insufficiency of the leg. ACA is caused by a Borrelia infection and serological testing will always show a significantly elevated titer to Borrelia. The disease is most often easily cured by 2-3 g of penicillin daily for two to three weeks.