Parasitic infections of the CNS can present with diverse clinical and radiological manifestations, ranging from focal lesions to diffuse meningoencephalitis.
These infections are more prevalent in tropical and subtropical regions and in immunocompromised individuals.
| Parasite | Disease | Common CNS Manifestation |
|---|---|---|
| Taenia solium | ‣ | Seizures, hydrocephalus |
| Echinococcus granulosus | ‣ | Cystic intracranial mass |
| Toxoplasma gondii | ‣ | Abscesses in immunocompromised |
| Plasmodium falciparum | ‣ | Diffuse encephalopathy |
| Naegleria fowleri | ‣ | Fulminant meningoencephalitis |
| Acanthamoeba spp. | ‣ | Subacute meningoencephalitis |
| Trypanosoma brucei | African sleeping sickness | Meningoencephalitis, somnolence |
| Toxocara canis/cati | Toxocariasis | Eosinophilic meningitis, myelitis |
| Schistosoma spp. | ‣ | Myeloradiculopathy, granulomas |
Parasitic diseases of central nervous system according to presentation.
Parasitic diseases of the central nervous system: lessons for clinicians and policy makers. Expert Review of Neurotherapeutics. Published online 2016. doi:https://doi.org/10.1586//14737175.2016.1155454
| Parasite | Typical Imaging Finding |
|---|---|
| Taenia solium | Cyst with scolex, ring-enhancing lesion, calcified nodules |
| Echinococcus | Large cysts with daughter cysts, no edema |
| Toxoplasma gondii | Ring-enhancing lesions in BG/corticomedullary junction (“target sign”) |
| Plasmodium falciparum | Diffuse edema, petechial hemorrhages |
| Naegleria fowleri | Hemorrhagic necrosis, diffuse brain swelling |
| Acanthamoeba spp. | Multifocal enhancing lesions with edema |
| Trypanosoma brucei | Periventricular hyperintensity, meningitis |
| Imaging Feature | Suggestive Infections |
|---|---|
| Multiple ring-enhancing lesions | Neurocysticercosis, toxoplasmosis, GAE, TB, metastases |
| Cyst with scolex | Neurocysticercosis (vesicular stage) |
| Large cyst with daughter cysts | Hydatid disease |
| T2 hyperintensity ± edema | Cerebral malaria, amoebiasis, toxoplasmosis |
| Diffusion restriction | PAM, cerebral abscess, lymphoma |
| Calcifications | Healed NCC (granular or nodular stage) |
| Basal ganglia involvement | Toxoplasmosis, GAE, malaria |