摘要： 目的   探讨中枢神经系统新型隐球菌感染的临床、影像学及病理学特点，复习相关文献，提高认识和诊断水平。方法   采用常规HE 染色、特殊染色和免疫组织化学染色方法对1 例右侧额叶隐球菌性肉芽肿患者的手术切除标本进行组织形态学观察和临床病理分析。结果   30 岁男性患者，无明显诱因突发肢体抽搐，伴短暂意识障碍。头部MRI 检查显示右侧额叶占位性病变，放射冠区结节状病灶；T1WI 呈等信号，T2WI 呈低信号，且伴明显环状强化影。大体标本剖面呈灰白、灰黄色，部分囊壁样，可见少量胶冻状物。常规HE 染色显示肉芽肿性炎症，增生的纤维组织之间有大量上皮样组织细胞、多核巨细胞和淋巴-单核细胞浸润，细胞内外可见无色或淡红色的酵母菌孢子，呈圆形或卵圆形，厚壁，有宽阔、折光性胶质样荚膜，体积大小不等，直径为4 ~ 20 μm，荚膜厚3 ~ 5 μm；特殊染色厚壁荚膜呈紫红色或蓝色，散在孢子单孢出芽；免疫组织化学染色可见多核巨细胞内成团隐球菌，CD68 表达阳性，孢子不着色。结论   隐球菌病是由新型隐球菌引起的亚急性或慢性真菌病，主要侵犯中枢神经系统和肺脏。中枢神经系统隐球菌感染主要包括隐球菌性脑膜炎（伴或不伴脑实质囊肿）和隐球菌脓肿（又称隐球菌瘤或隐球菌性肉芽肿），由于临床表现和影像学多样化，容易造成误诊，需提高警惕；尽早诊断和及时治疗是关键。

关键词: 隐球菌病, 肉芽肿, 额叶, 免疫组织化学

Abstract: Objective To explore the clinicopathological and imaging features of cryptococcal granuloma in central nervous system (CNS), and review related literatures to enhance the recognition and diagnostic level. Methods Retrospectively analysed clinicopathological, histopathological and immunohistochemical features and imaging findings of one case of cryptococcal granuloma in the right frontal lobe. HE staining, alcian blue-periodic acid-Schiff (AB-PAS) staining, Gomori silvermethenamine (periodic acid silvermethenamine, PASM) staining, and immunohistochemistry staining were used respectively. CD68 was determined. The related literatures were reviewed. Results A 30-year-old male patient presented with sudden limb convulsion and accompanied with temporary loss of consciousness before 6 d. Cranial computed tomography (CT) showed a nodular hyperdense lesion in the right frontal lobe. Cranial magnetic resonance imaging (MRI) examination demonstrated an enhancing mass in the right frontal lobe area, measuring 3.10 cm × 2.80 cm × 1.50 cm in dimension, which showed low T2-weighted signal intensity, contrasting with the surrounding hyperintense cerebral edema and irregular lobulated margin of the ring-enhancing lesion on T1WI. Grossly, grayish and (or) yellowish gray chunky tissues were found, measuring 2.80 cm × 2.50 cm × 1.50 cm. Pathological finding revealed a large number of cryptococcal lesions and granuloma formation. Final diagnosis was cryptococcal granuloma or cryptococcoma of the right frontal lobe. Conclusion Cryptococcosis is a subacute or chronic fungal disease caused by cryptococcus neoformans, mainly affects CNS and lungs. There are two main forms of infection of the CNS, which include meningitis (with or without parenchymal cysts) and cryptococcal abscess (cryptococcoma). Cryptococcal meningitis and meningoencephalitis are most common. Cryptococcal granuloma is rare. Cerebral cryptococcosis is often misdiagnosed, we should pay close attention to it. Early diagnosis and prompt treatment is crucial.

Key words: Cryptococcosis, Granuloma, Frontal lobe, Immunohistochemistry