Khandwala Kumail, Farooqi Joveria, Ali Rashid, Bakhshi Saqib Kamran, Anwar Shayan Sirat Maheen
Department of Radiology, Aga Khan University Hospital, Aga Khan University, Karachi Stadium Road, P.O. Box 3500, Karachi, 74800, Pakistan.
Section of Microbiology, Department of Pathology & Laboratory Medicine, Aga Khan University, Karachi, Pakistan.
Neuroradiology. 2025 Jan;67(1):25-36. doi: 10.1007/s00234-024-03510-z. Epub 2024 Nov 25.
The study aims to evaluate the magnetic resonance (MR) features of central nervous system (CNS) fungal infections and determine the associations between these findings and the type of fungus. Our main objective was to assess whether imaging can serve as a predictor for identifying the specific group of fungi responsible for the infection using microbiology and histopathology as a benchmark.
A retrospective analysis was done on 50 patients with proven CNS fungal infections. Fungal type was determined and grouped according to microbial classifications into four subtypes: hyalohyphomycetes, mucorales, yeasts and dematiaceous molds. MR findings were compared with histopathology/microbiology and associations between fungal groups were sought.
A total of 37 males and 13 females with a mean age of 39.3 years were included in the study. Aspergillus spp. infection (48%) was the most common. Most patients (54%) had an underlying risk factor for the infection. Pseudo-tumoral mass-like behavior was observed with Aspergillus, and the presence of meningitis was associated with yeast infections (p < 0.001). Of the 19 abscesses, 9 (47.3%) showed a dual rim sign on susceptibility-weighted imaging (SWI), and 10 (52.6%) showed intracavitary dot-like foci of dropouts on SWI. Both findings were statistically significant with dematiaceous molds (p = 0.04 and p = 0.009, respectively).
Although radiological characteristics are non-specific and can overlap with each type of fungi, our study shows that certain MR features can help radiologists point towards the causative type. More specifically, dot-like foci of susceptibility point towards abscesses caused by dematiaceous molds possibly owing to melanin pigment and metal chelation properties.
本研究旨在评估中枢神经系统（CNS）真菌感染的磁共振（MR）特征，并确定这些发现与真菌类型之间的关联。我们的主要目标是评估影像学检查能否以微生物学和组织病理学为基准，作为识别引起感染的特定真菌组的预测指标。
对50例经证实的中枢神经系统真菌感染患者进行回顾性分析。根据微生物分类确定真菌类型并分为四个亚型：透明丝孢霉、毛霉目、酵母和暗色霉菌。将MR表现与组织病理学/微生物学进行比较，并寻找真菌组之间的关联。
本研究共纳入37例男性和13例女性，平均年龄39.3岁。曲霉属感染（48%）最为常见。大多数患者（54%）有感染的潜在危险因素。曲霉感染可见假肿瘤样肿块表现，脑膜炎的存在与酵母菌感染相关（p<0.001）。在19个脓肿中，9个（47.3%）在磁敏感加权成像（SWI）上显示双环征，10个（52.6%）在SWI上显示腔内点状低信号灶。这两个表现与暗色霉菌均有统计学意义（分别为p=0.04和p=0.009）。
虽然影像学特征是非特异性的，且可能在每种真菌类型中重叠，但我们的研究表明，某些MR特征可帮助放射科医生指向致病类型。更具体地说，磁敏感点状病灶可能指向由暗色霉菌引起的脓肿，这可能归因于黑色素色素和金属螯合特性。
