The aim of this study is to determine the Toxocara seropositive rate among healthy people with eosinophilia. A total of 97 people residing in Seoul who were healthy and whose blood eosinophilia was over 10%, as shown by regular health check-ups in 2004, were subjected to this study. Their sera were tested by immunoblotting and ELISA with the antigen of larval Toxocara canis excretory-secretory (ES) protein. Sixty-five sera were band-positive (67.0%). The seropositve control sera were positive to band sizes of 66 kDa, 56 kDa, 32 kDa, and 13 kDa. In ELISA, 63 sera (65.0%) were positive to T. canis ES protein. There was no significant correlation between the IgG ELISA titer and the level of eosinophilia (r = 0.156, P = 0.156). As there were insufficient data to determine whether there were cross-reactions with other helminthic infections, or whether atopy occurred, further studies are required to verify the cause of the seropositive reactions against T. canis ES antigen. Toxocariasis seropositivity is suggested to be the major cause of eosinophilia, since the Toxocara seroprevalence among Korean rural adults was shown to be approximately 5%.
Antigens, Helminth/blood ; Carrier State/blood/*epidemiology ; Enzyme-Linked Immunosorbent Assay ; Eosinophilia/*complications ; *Health ; Humans ; Immunoblotting ; Seroepidemiologic Studies ; Toxocariasis/blood/complications/*epidemiology

The aim of this study is to determine the Toxocara seropositive rate among healthy people with eosinophilia. A total of 97 people residing in Seoul who were healthy and whose blood eosinophilia was over 10%, as shown by regular health check-ups in 2004, were subjected to this study. Their sera were tested by immunoblotting and ELISA with the antigen of larval Toxocara canis excretory-secretory (ES) protein. Sixty-five sera were band-positive (67.0%). The seropositve control sera were positive to band sizes of 66 kDa, 56 kDa, 32 kDa, and 13 kDa. In ELISA, 63 sera (65.0%) were positive to T. canis ES protein. There was no significant correlation between the IgG ELISA titer and the level of eosinophilia (r = 0.156, P = 0.156). As there were insufficient data to determine whether there were cross-reactions with other helminthic infections, or whether atopy occurred, further studies are required to verify the cause of the seropositive reactions against T. canis ES antigen. Toxocariasis seropositivity is suggested to be the major cause of eosinophilia, since the Toxocara seroprevalence among Korean rural adults was shown to be approximately 5%.
Antigens, Helminth/blood ; Carrier State/blood/*epidemiology ; Enzyme-Linked Immunosorbent Assay ; Eosinophilia/*complications ; *Health ; Humans ; Immunoblotting ; Seroepidemiologic Studies ; Toxocariasis/blood/complications/*epidemiology

Toxocariasis is one of the causes of pulmonary eosinophilic infiltrate that is increasing in Korea. This study was designed to identify the prevalence of toxocara seropositivity in patients with unexplained pulmonary patchy infiltrate and to evaluate associated factors. We evaluated 102 patients with unexplained pulmonary patchy infiltrate on chest computed tomography (CT) scan. As a control set, 116 subjects with normal chest CT were also evaluated. History of allergic disease, drug use, parasitic disease and raw cow liver intake were taken. Blood eosinophil count and total IgE level were measured. Specific serum IgG antibody to Toxocara canis larval antigen and specific IgG antibodies to 4 other parasites were measured by enzymelinked immunosorbent assay (ELISA). In the infiltrate group, 66.7% subjects were toxocara seropositive whereas 22.4% of the control group were seropositive (p< 0.001). In the infiltrate group, patients with a history of eating raw cow liver (odds ratio [OR], 7.8) and patients with eosinophilia (OR, 5.2) had a higher incidence of toxocara seropositivity. Thirty-five percent of toxocara seropositive patients with infiltrate exhibited migrating infiltrate and 48% had decreased infiltrate on the follow- up CT. We recommend that toxocara ELISA should be performed in patients with unexplained pulmonary patchy infiltrate, and that the eating of raw cow liver should be actively discouraged.
Adult ; Aged ; Animals ; Case-Control Studies ; Female ; Humans ; Immunoglobulin E/blood ; Korea ; Leukocyte Count ; Liver/parasitology ; Male ; Middle Aged ; Pulmonary Eosinophilia/diagnosis/*etiology/immunology ; Seroepidemiologic Studies ; Tomography, X-Ray Computed ; Toxocara/immunology ; Toxocariasis/*complications/diagnosis/epidemiology