A 57-year-old Chinese woman complained of multiple masses on her body surface for 2 years, mainly in the right cervical and retroauricular lymph nodes, with no tenderness, clear boundary, or mobility. In the absence of treatment, slow progressive enlargement and increase in numbers were noted in the masses, which were palpable on the axilla, chest wall, and groin, as well as unclear demarcation from the surrounding tissues, accompanied by itchiness of the affected skin surfaces. The patient had a medical history of tuberculosis, gastric polyp, and hysteromyoma.
Physical examination revealed two subcutaneous masses in the right posterior ear and neck measuring approximately 1 x 1 cm and 2 x 2 cm, respectively, which were solid in texture, with clear boundaries, and fixed to the skin. The skin surface was black, without tenderness, and with a rise in local skin temperature. The enlarged lymph nodes could be palpated on the chest wall and supraclavicular, axillary, and inguinal regions. Obvious scratches were found on the skin of the patient's whole body.
Ultrasonography revealed the size of retroperitoneal (maximum 2.2 x 1.2 cm2), bilateral neck (maximum 1.7 x 0.6 cm2 on the left side, 0.8 x 0.6 cm2 on the right side), bilateral supraclavicular (maximum 2.0 x 1.3 cm2 on the left side, 1.3 x 1.0 cm2 on the right side), bilateral axillary (maximum 2.8 x 1.1 cm2 on the left side, 2.9 x 1.8 cm2 on the right side), and bilateral inguinal (maximum 3.0 x 1.3 cm2 on the right side) superficial lymph nodes. Enlargement of multiple lymph nodes was found in all areas (Fig. 1). Many solid nodules with a maximum size of 2.7 x 1.6 cm2 and 1.9 x 0.6 cm2 were found in the right parotid gland and right posterior neck, respectively (Fig. 2). Numerous solid nodules were seen on the left chest wall with a maximum size of 1.5 x 1.0 cm2. Pulmonary computed tomography (CT) scan showed obsolete pulmonary tuberculosis in the upper lobe of both lungs and localized dilatation of right upper lobe and middle lobe bronchi. Abdominal CT showed slightly high density of the left kidney.  
Laboratory tests showed that the percentage of eosinophils in the patient's whole blood was 39.40% (normal value is 0.4-8%), eosinophil count was 2.68 x 109/L (normal value is 0.02-0.52 x 109/L), and erythrocyte sedimentation rate was 47 mm/h (normal value is 0-20 mm/h). Blood sugar, urea, creatinine, and bilirubin levels and liver and kidney function biomarkers were within normal range. No abnormality was found in the routine urine test. Serum total immunoglobulin E (IgE) level was > 5000 kU/L (normal value: < 100 kU/L), serum specific IgE level to Phadiatop was 1.01 KUA/L (inhalation allergen screening, normal value: < 0.35 KUA/L), and serum specific IgE level to fx5 was 1.04 KUA/L (food combination, normal value: < 0.35 KUA/L), detected with ImmunoCAP (Phadia 250; Thermo Fisher Scientific Inc.). Allergen patch test was negative. Rheumatism, rheumatoid factor, anti-nuclear antibody, complete parasite set, routine stool and urine, thyroid function, immunoglobulin G4, complement C3/C4, and D-dimer levels were normal.
After a complete examination, we resected the masses in the right neck, retroauricular and left axillary regions, and left chest wall directly. Postoperative pathological findings showed KD in the right neck, left chest wall, and left axillary lymph nodes (Fig. 3). Immunohistochemistry of the T lymphoid tissue suggested CD2, CD3, CD5, CD7, CD4, and CD8 positivity; BCL-6, CD10, and PD-1 negativity; no identified Reed-Sternberg (RS)-like cells (CD15 and CD30 negative) and proliferation of follicular dendritic cells (FDCs); and a nodular FDC network for CD21 (Fig. 4). The final diagnosis for this patient was KD. Low-dose radiotherapy may have been the best treatment, but she refused and only received glucocorticoid maintenance treatment after surgery; therefore, prednisone 60 mg QD orally was administered to the patient for 2 weeks and the dose was then gradually reduced over another 6 weeks. Lymph node enlargement ceased after 8 weeks of treatment. The patient is still taking prednisone 10 mg once a day, and the symptoms are well controlled even after 1 year.