<b style="line-height:1.5;"><span style="font-family:Verdana;">Background</span><span style="font-family:Verdana;">:</span></b><span style="font-family:'';line-height:1.5;"><span style="font-family:Verdana;"> Toxoplasmosis is an extremely rare disease that occurs in the hosts contact with cat and dog frequently. Most human acute infections go unnoticed in immunocompetent individuals, and gradually transformed into chronic infection. However, while host immunity significantly waned, the risk of reactivation of chronic toxoplasma infection is greatly increased. Reactivation of latent toxoplasmic infection often presents with fever, leukopenia, thrombocytopenia, neurological signs and pneumonia. However, for the non-specific clinical and biological signs and its fetal outcome, toxoplasmosis is often misdiagnosed and only revealed at autopsy. </span><b><span style="font-family:Verdana;">Case Presenation</span></b></span><b style="line-height:1.5;"><span style="font-family:Verdana;">:</span></b><span style="line-height:1.5;font-family:Verdana;"> We report a case hospitalized for a week history of cough, anorexia and fatigue with nasal bleeding for a day. After hospitalization, broad-spectrum antibiotherapy was started without a clear diagnosis of infection. Then the patient did a lot of investigation</span><span style="line-height:1.5;font-family:Verdana;">s</span><span style="line-height:1.5;font-family:Verdana;"> to search the cause of infection, but there were no positive findings. However, an unexpected discovery was detected from peripheral blood smears, shows 1</span><span style="font-family:'';line-height:1.5;"> </span><span style="line-height:1.5;font-family:Verdana;">-</span><span style="font-family:'';line-height:1.5;"> </span><span style="line-height:1.5;font-family:Verdana;">3</span><span style="font-family:'';line-height:1.5;"> </span><span style="font-family:'';line-height:1.5;"><span style="font-family:Verdana;">μm in diameter, scattered, short and bow like microorganisms on Day 39 of hospitalization.