Table 1
Parasite | Disease | Transmission & host | Most affected organs/systems | Characteristic imaging findings |
|---|---|---|---|---|
Protozoa | ||||
Plasmodium spp (P.falciparum, P. vivax, P. malariae, P. ovale) | Malaria | Vector (Anopheles mosquito) Human final host | Systemic disease | Hepatosplenomegaly Diffuse cerebral oedema Cerebral infarcts T2 hyperintensity in cortex, basal ganglia, and cerebellum ARDS |
Entamoeba histolytica | Amoebiasis | Fecal-oral (ingestion of cysts) Human final host | Gl tract Liver | Liver abscess |
Toxoplasma gondii | Toxoplasmosis | Fecal-oral (ingestion of cysts from cat faeces) Foodborne (ingestion of cyst-containing meat) Vertical (mother-foetus) Human final host | Systemic disease CNS | Cerebral ring enhancing lesions-”asymmetric target sign” |
Trypanosoma cruzi | American trypanosomiasis or Chagas disease | Vector (Triatomine bugs) Human final host | Gl tract Heart Nervous system | Megaoesophagus and megacolon Myocardiopathy |
Leishmania spp | Leishmaniasis | Vector (Phlebotomus sandflies) Human final host | Liver-spleen (kala-azar) Skin. Mucocutaneous | Hepatosplenomegaly Lymphadenopathy |
Cestodes (tapeworms) | ||||
Echinococcus spp (E. granulosus, E. multilocularis, E. vogeli, E. oligarthrus) | Echinococcosis or hydatid disease | Fecal-oral (ingestion of eggs) Human accidental intermediate host | Liver Lungs | Hydatid cysts |
Taenia solium | Cysticercosis and Taeniasis | Cysticercosis: Fecal-oral (ingestion of eggs) Human accidental intermediate host | Cysticercosis: CNS | CNS cysts-”cyst with dot sign” CNS nodular calcifications |
Trematodes (flukes) | ||||
Clonorchis sinensis (also Opisthorchis viverrini and O. felineus) | Clonorchiasis | Foodborne (ingestion of cyst-containing fish) Human final host | Biliary system | Dilated intrahepatic bile ducts |
Schistosoma spp | Schistosomiasis or bilharzia or snail fever | Direct contact (through skin) Human final host | Gl tract and liver (portal venous system) GU system (paravesical venous plexus) | Gl: Chronic liver disease signs Portal hypertension signs Periportal cuffing S. japonicum: liver capsule “turtle back” GU: Linear calcifications of urinary bladder and distal ureter walls |
Fasciola spp (F. hepatica, F. gigantica) | Fascioliasis or liver rot | Foodborne (ingestion of parasite-contaminated vegetables or water) Human final host | Liver Biliary system | Subcapsular liver lesions (linear, nodular, clustered) Bile duct dilatation Hepatic subcapsular haematoma |
Nematodes (roundworms) | ||||
Ascaris lumbricoides | Ascariasis | Fecal-oral (ingestion of eggs) Human final host | Gl tract Biliary system Lungs | Adult worms inside bowel lumen or biliary tree Lungs: Patchy ground-glass infiltrates |
Strongyloides stercolaris | Strongyloidiasis | Direct contact (through skin) Autoinfection Human final host | Lungs and bronchi Gl tract | Lungs: Miliary nodules, interstitial infiltrates, alveolar infiltrates Bowel wall oedema |
Dracunculus medinensis | Dracunculiasis or Guinea worm disease | Foodborne (ingestion of water contaminated with parasite-infected water fleas) Human final host | Subcutaneous tissues | “Worm-like" calcifications in soft tissues |
Anisakis spp | Anisakiasis | Foodborne (ingestion of worm-containing fish) Human accidental intermediate host | Gl tract | Bowel wall submucosal oedema Oedema of Kerckring’s folds Ascites |