The patient’s multiple pink, subtly annular patches after recent travel to Lyme-endemic areas of the United States demonstrated a classic manifestation of disseminated Lyme disease. An enzyme-linked immunosorbent assay was positive for Borrelia burgdorferi IgM and IgG antibodies, confirming an acute infection.
While not usually necessary, skin biopsy shows a nonspecific perivascular cellular infiltrate that may be comprised of histiocytes, lymphocytes, and plasma cells. Spirochetes are not typically seen, but they may be identified with antibody-labeled or silver stains.
Lyme disease initially manifests as localized disease with erythema migrans, a targetoid lesion on the skin that appears at the site of the tick bite. This initial stage develops within the first few weeks of the bite and may be accompanied by fatigue and a low-grade fever.
If left untreated, the infection may progress to early disseminated disease, which occurs weeks to months after the initial bite. This second stage of Lyme disease manifests with multiple erythema migrans lesions on additional parts of the body, indicating spirochete dissemination through the bloodstream and lymphatic system. Early disseminated disease may also include borrelial lymphocytoma, Lyme neuroborreliosis, and cardiac conduction abnormalities such as AV block.
The third stage of Lyme disease, late Lyme disease, occurs months to years after an initial infection that has gone untreated. The key feature of this stage is arthritis, which tends to affect the knees and may be migratory in nature. Neurological symptoms such as encephalopathy and polyneuropathies may also develop. A minority of patients with late Lyme disease may develop acrodermatitis chronica atrophicans, a rash that typically occurs on the dorsal hands and feet as blue-red plaques that turn the affected skin atrophic.1
This patient was treated with a 3-week course of oral doxycycline 100 mg twice daily and was referred to an infectious disease specialist for further work-up of systemic symptoms, given the risk for cardiac pathology in disseminated Lyme disease.
Photo courtesy of Le Wen Chiu, MD. Text courtesy of Le Wen Chiu, MD, Department of Dermatology, University of New Mexico School of Medicine, Albuquerque, and Daniel Stulberg, MD, FAAFP, Professor and Chair, Department of Family and Community Medicine, Western Michigan University Homer Stryker, MD School of Medicine, Kalamazoo.