gms | German Medical Science

Vorgeschichte: The skin changes began 3 years ago and were edematous, dry and thin, with erythematous/violaceous macules and patches. The patient described that he bled easily only in the affected areas. The skin changes were – aside from the heliotropic exanthema – strictly one-sided. A review of systems aside from the previously described symptoms and fatigue was negative.

Leitsymptom bei Krankheitsmanifestation: A 48-year-old man presented to Rheumatology with a heliotropic exanthem, sicca complex, and skin changes of the extensor surfaces of the right elbow, knee, and hand with suspected Sjögren’s-syndrome or dermatomyositis.

Diagnostik: Laboratory tests showed a significantly elevated soluble interleukin-2 receptor, neopterin, and angiotensin-converting-enzyme. Additionally, gamma globulins and β-2-microglobulin were strongly elevated. Anti-nuclear antibodies using immunofluorescence and extractable nuclear antigens using ELISA were negative. Due to the elevated markers of T-cell activation and lymphoproliferation sarcoidosis and lymphoma were also initially suspected. Two-tiered serological testing for borreliosis showed highly positive IgG-antibodies in ELISA and Western Blot. A skin biopsy was taken from laterocaudal of the patella. The histology showed infiltration with lymphocytes and plasma cells and was not consistent with dermatomyositis. An additional staining showed possible spirochetal bacteria within the blood vessels. Based on the clinical examination, serology, and histology a diagnosis of acrodermatitis chronica atrophicans was made.

Therapie: The patient was discharged and doxycycline (no neurological symptoms were present) 100mg twice daily for 30 days was initiated.

Weiterer Verlauf: In serial follow-up examinations the skin changes regressed, and the gamma globulins and markers of T-cell activation slowly normalized over a period of months.

This case illustrates how a chronic infection can mimic autoimmune diseases. Additionally, the kinetics showed that the aforementioned biomarkers required months following the end of the antibiotic therapy until their values normalized. Finally, the utility of skin biopsy for rheumatological diseases and their differential diagnoses was underscored.

Disclosures: None declared