Eosinophilic Fasciitis Associated with Autoimmune Thyroiditis
A 45-year-old woman was referred to our hospital to evaluate the swelling on both the forearms lasting from past 3 months. She had intermittent cramp-like pain on both the forearms, which got aggravated by movement. The patient was placed on non-steroidal anti-inflammatory drugs intermittently. Raynaud's phenomenon was absent on past history.\nUpon physical examination, both the upper extremities showed marked swelling without pitting or erythematous change, and there was no swelling in the hands. However, physician was able to pinch her skin on both the forearms. Laboratory findings revealed the white cell count of 7,200/mm3 with 13.8% of eosinophils (absolute counts 993/mm3), hemoglobin of 10.8 g/dl and platelet count of 319×103/mm3. Stool examination for the presence of parasites was negative. Peripheral blood smear showed normocytic and normochromic red blood cells and no atypical leukocytes were seen except for an increased level of eosinophils. Liver function test, renal function test, and levels of CRP, glucose, creatinine kinase, calcium, and phosphate were normal. Esophagogastroduodenoscopy, colonoscopy, ultrasonography, and chest radiography revealed no abnormal findings. The titer level of anti-nuclear antibody in IT-1 cell was 1:40 with speckled pattern, but rheumatoid factor and anti-neutrophil cytoplasmic antibody wrere negative.\nBased on thyroid function test, the levels of thyroid stimulating hormone (TSH) and free thyroid hormone-4 (FT4), were 4.86 uIU/mL (normal 0.27~4.2 uIU/mL) and 0.85 ng/dL (normal 0.93-1.7 ng/dL), respectively. The titre values of antithyroglbulin antibodies and antimicrosomal antibodies were 1:1600 and 1:1600, respectively. No nodule was detected during ultrasonography of thyroid and there was no hot uptake by thyroid scan.\nMRI demonstrated swelling and increased signal of muscles like extensor carpi ulnaris, extensor digitorum longus, and extensor carpi radialis, and there was thickening and edematous change of fascia around the muscles (). Full-thickness wedge biopsy on extensor carpi radialis revealed the presence of thickened fibrous fascia with perivascular infiltration of lymphocytes, plasma cells and few eosinophils, and these findings were compatible with eosinophilic fasciitis (). To the patient, we initially prescribed prednisone 30 mg/day, cetirizine 10 mg/day and levothyroxine sodium 0.1 mg/day. Hypereosinophilia disappeared immediately after treatment with prednisone and induration on both the forearms also improved gradually.