Multiple-site venous thromboembolism in acute toxoplasmosis: report of two cases

Venous thrombosis triggered by infection (immunothrombosis) is increasingly recognized during viral infections, but it can also occur in bacterial and parasitic infections. Reports of systemic thromboembolism during acute toxoplasmosis are exceptional, usually linked to pre-existing risk factors. We describe two adults with multisite venous thrombosis later diagnosed with primary Toxoplasma gondii infection. The first case was a healthy adult with fever and pulmonary embolism and splanchnic thrombosis. Serology indicated a primary T. gondii infection, and T. gondii DNA was detected in a lymph node showing Piringer-Kuchinka lymphadenitis. The second case involved an immunocompromised adult with fever, seizures, cerebral infarction, cerebral venous sinus and jugular thrombosis, and splanchnic thrombosis. T. gondii serology confirmed recent infection, and Toxoplasma DNA was retrieved in blood. Anticoagulation therapy was administered to both, with specific treatment initiated in the second case due to multi-organ involvement and an impaired immune state. Our findings provide new insights into the association between venous thromboembolism and acute toxoplasmosis and support adding T. gondii testing for febrile patients with unexplained venous thrombosis.