A case of dermatopathic lymphadenopathy associated with hypereosinophilic syndrome.

Dear Editor, A 42-year-old man presented with a 4-week history of erythematous, maculopapular rash over his whole body (Fig.1), shortness of breath and generalised lymphadenopathy for 1 week. Clinical examination showed erythroderma with multiple lymph nodes in the cervical, axillary and groin areas. The lymph nodes were firm, mobile, non tender and were not attached to underlying structures. The lymph nodes were about 3.0 cm by 2.0 cm in size. Clinical examination of the respiratory system showed prolonged expiratory phase with diffuse wheeze over both lungs. There was no evidence of hepatosplenomegaly. Complete blood picture showed a raised absolute eosinophil count of 1.6 k/ul. His immunoglobulin (Ig) E was raised at 5380 IU/ml (normal range 0 to 165). His liver biochemistry, urea and electrolytes were all unremarkable. Repeated stool for ova and parasites (4 samples) were negative. His erythrocyte sedimentation rate, C-reactive protein, antineutrophilic cytoplasmic antibody, antinuclear antibody, complement 3, complement 4, IgA, IgG, IgM, rheumatoid factor, anti-extractable antibody, anticardiolipin antibody, serum tryptase, chest x-ray, urine for microscopy and urine for porphyrin were all unremarkable or within the normal range. The patient was also negative for hepatitis B surface antigen, hepatitis C antibody and Epstein Barr virus DNA. Whole body positron emission tomography-computerised tomography showed clusters of enlarged lymph nodes in the bilateral inguinal, axilla, jugular chains and occipital regions. These lymph nodes were minimally hypermetabolic lymphadenopathy. The standardised uptake value (SUVmax) of all these lymph nodes was 2.33. No enlarged lymph nodes were detected in the mediastinum, hilar, retroperitoneum or pelvic cavity. No hypermetabolic focal lesions were detected within the solid organs to suggest the presence of 18F-fludeoxyglucose-avid neoplasm. On computerised tomography, prominent lymph nodes were seen in the bilateral cervical, subsegmental regions, bilateral axillary regions and bilateral inguinal regions. The largest lymph node was located in the right inguinal region at 3 cm in diameter. No abnormality was detected in the thorax, abdomen, pelvis and skeleton. A skin biopsy showed a minimally inflamed skin tissue with increased eosinophil in the superficial dermis. The eosinophils were 25/high-powered field (Fig. 2). Focal mild increase in vascularity was noted in the dermal papillae. Serial step sectioning did not show any evidence of vasculitis. There was also no abnormal lymphoid infiltrate seen. Biopsy of the right inguinal lymph nodes was subsequently performed. The 2 inguinal lymph nodes showed prominent sinus histiocytosis together with many pigmented macrophages. Mild follicular hyperplasia was observed. These appearances were typical of dermopathic