Department of Neurosurgery, Wits Medical School, Chris Hani Baragwanath Academic Hospital, 7, York Road, Parktown, Johannesburg 2193, South Africa.
Neurol Sci. 2012 Dec;33(6):1423-8. doi: 10.1007/s10072-012-0960-x.
Cerebellar mass lesion is an uncommon presentation of toxoplasmosis. The authors report one rare case in an 11-month-old HIV/AIDS female infant who presented with deterioration in her developmental milestones. CT scan revealed a ring-enhancing mass lesion in the right cerebellar hemisphere with secondary obstructive hydrocephalus. A ventriculoperitoneal shunt was inserted prior to posterior fossa decompression and biopsy of the lesion. The specimens obtained were divided into two. One specimen was sent for histological diagnosis immediately after surgery while the second specimen was preserved until the release of the histology report. The initial histopathology report indicated a neoplastic process. Immunohistochemical stains were attempted but interpreted with difficulty due to severe tissue necrosis. After waiting for close to 6 weeks without a definite histological diagnosis, the preserved second specimen was sent for histological analysis as a fresh specimen, and reported a diagnosis of toxoplasmosis. This case presented diagnostic challenges to the authors whose radiological impressions of either a neoplastic lesion or a tuberculoma (based on our local neuroepidemiology) were reinforced by intraoperative findings highly suggestive of tuberculoma but which contrasted with the histological report, first as a neoplastic lesion and later toxoplasmosis. Although cerebellar toxoplasmosis is a rare complication of HIV/AIDS, this case report shows that toxoplasmosis should not be overlooked as a differential diagnosis of ring-enhancing cerebellar masses in HIV/AIDS patients irrespective of the patient's age and the absence of constitutional symptoms of toxoplasmosis.
小脑肿块病变是弓形虫病的一种不常见表现。作者报告了一例罕见的 11 个月大的 HIV/AIDS 女性婴儿病例，该婴儿出现发育里程碑恶化。CT 扫描显示右小脑半球有一个环形增强的肿块病变，伴有继发性梗阻性脑积水。在进行后颅窝减压和病变活检之前，插入了脑室-腹腔分流管。获得的标本分为两份。一份标本在手术后立即送检进行组织学诊断，另一份标本保存，直到组织学报告发布。最初的组织病理学报告表明存在肿瘤过程。尝试进行免疫组织化学染色，但由于严重的组织坏死，解读困难。在等待近 6 周没有明确的组织学诊断后，将保存的第二份标本作为新鲜标本进行组织学分析，并报告了弓形虫病的诊断。该病例给作者带来了诊断挑战，他们的影像学印象是肿瘤病变或结核瘤（基于我们当地的神经流行病学），术中发现高度提示结核瘤，但与组织学报告相矛盾，最初是肿瘤病变，后来是弓形虫病。尽管小脑弓形虫病是 HIV/AIDS 的罕见并发症，但本病例报告表明，无论患者年龄大小以及是否存在弓形虫病的全身症状，都不应忽视弓形虫病作为 HIV/AIDS 患者环形增强小脑肿块的鉴别诊断。
