Which parasite infection is a concern for pregnant women and immunocompromised individuals, can cause chorioretinitis and ring-enhancing brain lesions, and is transmitted via raw meat or cat feces?

Which parasite infection is a concern for pregnant women and immunocompromised individuals, can cause chorioretinitis and ring-enhancing brain lesions, and is transmitted via raw meat or cat feces?

• A. Entamoeba histolytica
• B. Giardia lamblia
• C. Cryptosporidium
• D. Toxoplasma gondii

Answer: (D)

Think about a protozoan infection that humans can acquire from cat feces or undercooked meat and that poses special risks during pregnancy and in people with weakened immune systems. Toxoplasma gondii fits this scenario: it can cross the placenta and cause congenital toxoplasmosis with chorioretinitis, and in immunocompromised individuals, reactivation leads to toxoplasmic encephalitis characterized by multiple ring-enhancing lesions on brain imaging. This combination of ocular involvement and distinctive brain imaging findings in the relevant patient groups is classic for toxoplasmosis. The other parasites listed mainly cause gastrointestinal illness and do not typically produce both chorioretinitis and brain ring-enhancing lesions in these contexts.

Think about a protozoan infection that humans can acquire from cat feces or undercooked meat and that poses special risks during pregnancy and in people with weakened immune systems. Toxoplasma gondii fits this scenario: it can cross the placenta and cause congenital toxoplasmosis with chorioretinitis, and in immunocompromised individuals, reactivation leads to toxoplasmic encephalitis characterized by multiple ring-enhancing lesions on brain imaging. This combination of ocular involvement and distinctive brain imaging findings in the relevant patient groups is classic for toxoplasmosis. The other parasites listed mainly cause gastrointestinal illness and do not typically produce both chorioretinitis and brain ring-enhancing lesions in these contexts.