Abstract：
Familial hemophagocytic lymphohistiocytosis (FHL) is a genetically heterogeneous disorder which is less typical in adults than pediatric patients. In this study, we reported a rare case of adult-onset FHL3 with progressive lymphocytosis and lymphocytic interstitial pneumonia (LIP). A 20-year old female was admitted to our institution for persistent cough with fever. A chest high-resolution computed tomography (HRCT) scan showed diffuse bilateral ground glass opacities (GGO). A lung biopsy revealed infiltration of lymphocyte in the pulmonary interstitium. The patient was treated with corticosteroids and immunosuppressants, followed by significant clinical improvement although lymphocytosis still persisted. The definitive diagnosis of FHL was based on whole genome sequencing by which heterozygous mutations in UNC13D gene were identified. Lymphocytosis may be a remarkable feature of some patients with FHL. Performing gene sequencing is important to improve the recognition of FHL to avoid misdiagnosis.
摘要：
家族性噬血细胞性淋巴组织细胞增生症（FHL）是一种遗传异质性疾病，在成人中不如儿科患者典型。在这项研究中,我们报道了一例罕见的成人发病FHL3合并进行性淋巴细胞增多和淋巴细胞性间质性肺炎(LIP)的病例.一名20岁女性因持续咳嗽伴发烧入院。胸部高分辨率计算机断层扫描（HRCT）扫描显示弥漫性双侧磨玻璃影（GGO）。肺活检显示肺间质中淋巴细胞浸润。患者接受皮质类固醇和免疫抑制剂治疗，随后显著的临床改善，尽管淋巴细胞增多仍然存在。FHL的最终诊断基于全基因组测序，通过测序鉴定UNC13D基因的杂合突变。淋巴细胞增多可能是某些FHL患者的显着特征。进行基因测序对于提高FHL的识别以避免误诊很重要。
