"Once in the CNS, the Aspergillus hyphae invade the walls of both small and large blood vessels 1,2. This either results in initial thrombosis leading to infarction, often followed by haemorrhage (in 25%), or development of mycotic aneurysms which can haemorrhage 1-3. This haemorrhage may lead to further parenchymal seeding of Aspergillus, resulting in infectious cerebritis and eventual brain abscess formation, often multiple in nature3."
"cerebral infarction(s) with or without associated haematoma(s) in a random distribution, although more likely to affect perforating artery territories 1-3"
"cerebral infarction(s) with or without associated haematoma(s) in a random distribution, although more likely to affect perforating artery territories 1-3"
"CT findings can be often non-specific but in keeping with at least one of the main three aforementioned findings that are characteristic of CNS aspergillosis 1-2. Detecting multiple such lesions in an immunosuppressed patient should prompt further investigation with MRI."
"Rarely, CNS aspergillosis can present with a granulomatous tumour-like mass lesion 6,7. These, as described in case reports, are often hypo-to-isointense on T1-weighted images, hypointense on T2-weighted images, and demonstrate contrast enhancement on post-gadolinium T1-weighted images, but there is thought to be considerable variation 7,8."
"CNS aspergillosis results from angioinvasive infection of the central nervous system by the fungus Aspergillus spp. Along with CNS cryptococcosis, it is one of the most common fungal opportunistic infections of the central nervous system."
"There are two mechanisms of spread of Aspergillus spp. to the CNS 1-3. Firstly, as per the pathogenesis of angioinvasive aspergillosis, spores of a variety of Aspergillus spp., most commonly Aspergillus fumigatus, are inhaled and proliferate in the alveoli, where the hyphae invade pulmonary arteries and gain access to the systemic circulation in 25-50% of cases 4. Once in the systemic circulation, spores can haematogenously spread to the CNS 1-4. Aspergillosis can also directly spread to the CNS via the paranasal sinuses, where it may manifest as invasive fungal rhinosinusitis 1-3."
"Rarely, CNS aspergillosis can present with a granulomatous tumour-like mass lesion 6,7. These, as described in case reports, are often hypo-to-isointense on T1-weighted images, hypointense on T2-weighted images, and demonstrate contrast enhancement on post-gadolinium T1-weighted images, but there is thought to be considerable variation 7,8."
Expected headings
"Aspergillus abscess and invasive fungal rhinosinusitis"
"Aspergillus infarction"
"Other features"
"Patients with CNS aspergillosis have a very varied, and often subtle, presentation, making initial diagnosis difficult 1,2. However, the most common presenting features, with or without fever, are 1,2:"
"focal neurological signs (e.g. hemiparesis, dysarthria)"
"There are two mechanisms of spread of Aspergillus spp. to the CNS 1-3. Firstly, as per the pathogenesis of angioinvasive aspergillosis, spores of a variety of Aspergillus spp., most commonly Aspergillus fumigatus, are inhaled and proliferate in the alveoli, where the hyphae invade pulmonary arteries and gain access to the systemic circulation in 25-50% of cases 4. Once in the systemic circulation, spores can haematogenously spread to the CNS 1-4. Aspergillosis can also directly spread to the CNS via the paranasal sinuses, where it may manifest as invasive fungal rhinosinusitis 1-3."
"Rarely, CNS aspergillosis can present with a granulomatous tumour-like mass lesion 6,7. These, as described in case reports, are often hypo-to-isointense on T1-weighted images, hypointense on T2-weighted images, and demonstrate contrast enhancement on post-gadolinium T1-weighted images, but there is thought to be considerable variation 7,8."