Singh Neha, Fagan Kiley K, Grider Douglas J
Virginia Tech Carilion School of Medicine, Roanoke, VA, USA.
Section of Dermatology, Department of Internal Medicine, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA.
Case Rep Dermatol Med. 2022 Sep 5;2022:3506738. doi: 10.1155/2022/3506738. eCollection 2022.
Interstitial mycosis fungoides is a rare histopathologic variant of mycosis fungoides that may resemble interstitial granuloma annulare, inflammatory morphea, and interstitial granulomatous dermatitis. Reported is a case of a 62-year-old African American female who presented with an asymptomatic, progressive rash of the left underarm and abdomen with histologic features suggestive of granuloma annulare. Biopsies revealed an interstitial pattern of cells in the dermis with prominent small aggregates of atypical lymphocytes, a few atypical lymphocytes in the lower epidermis, and a mild increase in dermal mucin. Immunohistochemistry staining revealed the atypical lymphocytes to be positive for CD3 and CD8 and negative for CD4 and CD7, an aberrant immunoprofile. Mixed in the dermis with the atypical lymphoid cells were a few CD68 positive histiocytes and S100 protein positive dermal dendritic cells. T-cell receptor beta gene rearrangement studies showed nearly the same clonal peaks for TCRB rearrangement in two biopsy specimens from separate sites, all supporting a diagnosis of interstitial mycosis fungoides. The patient is undergoing treatment with full body narrowband UVB (nbUVB) phototherapy with notable improvement in skin discoloration and resolution of several abdominal lesions. A diagnosis of interstitial mycosis fungoides is challenging to make based on clinical features alone and is often clinically misdiagnosed. Awareness of histopathologic features is critical to make an accurate diagnosis and thus patient management.
间质性蕈样肉芽肿是蕈样肉芽肿一种罕见的组织病理学变异型，可能类似环状肉芽肿、炎症性硬斑病和间质性肉芽肿性皮炎。报告了一例62岁非裔美国女性患者，其左腋下和腹部出现无症状的进行性皮疹，组织学特征提示环状肉芽肿。活检显示真皮内细胞呈间质模式，有明显的非典型淋巴细胞小聚集，下表皮有少量非典型淋巴细胞，真皮黏蛋白轻度增加。免疫组织化学染色显示非典型淋巴细胞CD3和CD8阳性，CD4和CD7阴性，免疫表型异常。在真皮中与非典型淋巴细胞混合的有少量CD68阳性组织细胞和S100蛋白阳性真皮树突状细胞。T细胞受体β基因重排研究显示，来自不同部位的两份活检标本中TCRB重排的克隆峰几乎相同，均支持间质性蕈样肉芽肿的诊断。该患者正在接受全身窄谱中波紫外线（nbUVB）光疗，皮肤变色明显改善，腹部多处皮损消退。仅根据临床特征诊断间质性蕈样肉芽肿具有挑战性，临床上常被误诊。了解组织病理学特征对于准确诊断及患者管理至关重要。
