Acta Dermato-Venereologica 99-1CompleteContent | Page 25

99 SHORT COMMUNICATION Langerhans Cell Histiocytosis with Lymph Node Involvement Presenting as Erythroderma Huiqin ZHU 1 , Yannan MA 2 , Ling SUN 1 , Rongxin ZHANG 1 , Li LV 3 and Aoxue WANG 1 * Departments of 1 Dermatology and Venereology and 3 Pathology, The Second Hospital of Dalian Medical University, Dalian 116027, and 2 Department of Dermatology and Venereology, Liaocheng People’s Hospital, Liaocheng, China. E-mail: [email protected] Accepted Sep 4, 2018; Epub ahead of print Sep 5, 2018 Langerhans cell histiocytosis (LCH) represents a group of rare and clinically heterogeneous conditions of unknown etiology (1). Although most LCH cases appear in pediatric patients, the disease does occur de novo in adults, with an estimated incidence of 1–2 per million. Most adult LCH cases involve only a single organ system, such as the bones or lungs. Diagnosis of LCH is generally de- pendent on biopsy and is made based on the observation of inflammatory cell infiltration with large numbers of histiocytic cells and Langerhans cells staining positive for S100 and CD1a (1). Here we report an unusual case of LCH involving the lymph nodes that presented with the clinical features of erythroderma. CASE REPORT A 75-year-old Chinese man had a 2-month history of pruritic papular eruption on his trunk and limbs that began following an exposure to rain. The rash had rapidly progressed to generalized exfoliative dermatitis in a 2-week period. The patient had expe- rienced slight weight loss and fatigue for the previous one week but denied other systemic complaints including fever, expectoration, diarrhea, bone pain, and jaundice. Physical examination revealed enlarged bilateral axillary and inguinal lymph nodes exceeding 1 cm in diameter. Skin examinations revealed generalized uniform erythematous macules and diffuse scaling on the whole body (Fig. 1A, Fig. S1A 1 ). Blood tests revealed leukocytosis (14.61×10 9 cells/l) with a predominance of eosinophils (21.71%), anemia with low hemoglobin (119 g/l), and increases in the erythrocyte sedi- mentation rate, C-reactive protein and IgE (556 IU/ml) above the normal ranges. Chest X-rays and computed tomography (CT) scans showed mild interstitial changes. No Sézary cells were found in the peripheral blood. Routine studies included bacterial and fungal cultures from the skin and measurement of serum electrolyte, creatinine, and transaminase levels. Skull and abdominal CT scans showed normal results, and no bone alterations were observed. https://www.medicaljournals.se/acta/content/abstract/10.2340/00015555-3030 1 A skin biopsy of the affected area indicated hyperkeratosis, parakeratosis, acanthosis, and intercellular edema, with capillary dilation in the upper dermis and inflammatory infiltrate consisting of lymphocytes and eosinophils, collectively suggesting a case of superficial dermatitis (Fig. S1B, C 1 ). Histological examination of the inguinal node revealed destruction of the lymph node struc- ture as well as tumor cell infiltration. Large cells with grooved nuclei containing compact chromatin along with eosinophils and plasma cells also were observed (Fig. 1B, Fig. S1D 1 ). These cells stained positively for S-100 protein and CD1a upon immunoche- mical analysis, and thus, a definitive diagnosis of LCH could be made (Fig. 1C, D). Upon diagnosis of LCH, the patient was initially treated with oral methylprednisolone (40 mg/day) and application of a topical emollient to the affected areas daily. The sizes of the lymph nodes in the axillary and inguinal regions were significantly reduced after 2 weeks of these initial treatments, and the skin eruptions had improved. Improvements in the laboratory results also were noted. After 2 weeks of treatment, the methylprednisolone dose was tapered by 5 mg every 2 weeks to a maintenance dose of 5 mg/day. LCH in this patient responded completely to treatment, and thus, methylprednisolone use was discontinued after 3 months. No recurrence was observed during the 2-year follow-up. DISCUSSION Erythroderma, also known as exfoliative dermatitis, is an inflammatory reaction of the skin that is often secondary to a variety of causes (2). The most common causative factors are previous dermatoses, such as psoriasis and atopic dermatitis, followed by drug reaction, malignancy, or idiopathic causes. As this condition has received more attention, more unusual underlying dermatoses for erythro­ derma have been reported. To our knowledge, our case pre- sented is the third documented adult case of LCH involving the lymph nodes first manifesting as erythroderma (2, 3). In general, drug therapy for erythroderma consists of to- pical and/or systemic medications based on the underlying etiologies (2). The severe generalized skin inflammation Fig. 1. Langerhans cell histocytosis. (A) Generalized uniform erythematous macules and diffuse scaling affecting the patient. (B) Higher magnification images of lymph node showing large cells with grooved nuclei (arrows) and eosinophils. (H&E ×400). (C, D) Immunohistochemical staining revealed that the tumor cells were positive for CD1a (×200) and S-100 protein (×200). This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica. doi: 10.2340/00015555-3030 Acta Derm Venereol 2019; 99: 99–100