Prevalence of congenital and acquired toxoplasmic uveitis as evidenced by two serologic methods.

Anti Toxoplasma antibodies were sought in 34 patients with uveitis and 20 healthy individuals by IHAT and IFAT. The total sero-positivity rate was 26.5%. The prevalence was significantly higher among patients with posterior (42.9%) than with anterior uveitis (7.1%) and control (10%) indicating significant role of Toxoplasma as an aetiologic agent of posterior uveitis. 14.4% of patients with seropositive uveitis were considered to be due to primarily acquired Toxoplasma infection as evidenced by their significant higher IFAT mean titre (576.7 +/- 322.1) than IHAT (48 +/- 18.5). The reported toxoplasmic anterior uveitis case is most probably secondary to posterior involvement.

Toxoplasmosis and pregnancy: an analytical study in Zagazig, Egypt.

The sera of 72 women with a history of abortion (sporadic or habitual abortion) or perinatal complications were examined for Toxoplasma antibodies using indirect immunofluorescent antibody test (IFAT). It was found that 27.8% of them were positive for toxoplasmosis with geometric mean titre of 1/64. Also sera of 34 women with normal obstetric history as a control group were examined. 11.8% of them were positive for toxoplasmosis with geometric mean titre 1/16. The difference between the control group and complicated group was found to be statistically significant. The histopathological picture of placenta of positive cases showed characteristics of toxoplasmic placentosis with detection of the organism in fixed paraffin sections using HX and E, PAS or Giemsa stains.

Effect of Hymenolepis nana on the mouse ileal mucosal cells: histochemical studies.

Histochemical studies of the ileal mucosal cells of mice experimentally infected with H. nana revealed definite increase in mucous secretions indicating increased activity of the goblet cells in response to mucosal irritation. The activity of acid phosphatase was also increased representing a sort of defence mechanism against the attached worms. The activities of ATP-ase and NADH diaphorase enzymes were decreased indicating disturbance in the metabolic and transport processes and in the absorptive function of the intestinal epithelial cells.

Serological studies on toxoplasmosis in Zagazig slaughterhouse.

This study intended to estimate the prevalence of Toxoplasma antibodies among farm animals in Zagazig slaughterhouses using indirect haemagglutination test (I.H.A.T.) and to evaluate the occupational exposure to infected animals and meat among abattoir workers. 25% of the tested animals were seropositive 19.2% of the exposed persons showed positive reactions while in a control group it was 12% with statistically insignificant difference.

The role of single sample detection of specific anti-Toxoplasma IgM in accurate evaluation of seroconversion during acquired toxoplasmosis.

Specific IgM anti-Toxoplasma antibodies were sought in 94 serum samples by means of D.S. IgM ELISA. These antibodies were detected in all cases of acute toxoplasmic lymphadenopathy, but up to 13 months from onset of symptoms and in out of 20 patients with chronic toxoplasmosis and in one out of 20 seronegative individuals. They were neither detected in samples from 4 infants with high IgG IFAT titres associated with hydrocephalus and cerebral calcification, nor in samples from patients containing rheumatoid factors and those with lymphoma or infectious mononucleosis. Thus the detection of IgM antibodies seems non decisive mean for identifying infected infants and for determination of the exact date of acquiring the infection.

Cell-mediated immune response in experimental infection with H. heterophyes.

Experimental infection of puppies with Heterophyes heterophyes was associated with marked cell-mediated immune response that manifested itself by increase of T-cell count and leucocyte migration. The degree of cell-mediated immune response was inversely proportional to the intensity of infection. The significance of the results was discussed.

Echinococcosis in camels as revealed by indirect haemagglutination test in Belbas.

This study aimed to estimate the prevalence of Echinococcus antibodies in camels using the indirect haemagglutination test (I.H.A.T.). Out of 100 camels, 27 camels were seropositive.

Effect of some drugs on some histopathological and immunological aspects of experimental trichinosis in albino rats.

The present work is concerned with study of the effects of praziquantel, thiabendazole, mebendazole, cyclophosphamide and cortisone on histopathology of the small intestine (during intestinal phase) and skeletal muscles (during muscular phase), in addition to T. lymphocytes count and serum IgG estimation in experimental trichinosis in albino rats. Praziquantel has no effect on the histopathology of small intestine or skeletal muscles. Thiabendazole and mebendazole treatment resulted in complete eradication of Trichinella spiralis worms of small intestine and marked reduction of larval infection (mild infection) of skeletal muscle. Praziquantel, thiabendazole and mebendazole did not affect significantly the T. lymphocytes count of the host during the intestinal phase. Cyclophosphamide and cortisone suppressed the cellular immunity (T. lymphocytes) and accordingly enhanced the parasitic infection in histopathology of both phases. All the drugs tested induced significant reduction of T. lymphocytes in muscular phase (which may be due to parasitic infection itself) and insignificant effect on IgG level in both phases.

Cross-reactions in immunodiagnosis of patients infected with Schistosoma, Fasciola and Heterophyes using ELISA.

Cross-reactions in immunodiagnosis using schistosomal soluble egg antigen (SEA) and Fasciola adult worm antigen in cases with fascioliasis, heterophyiasis and schistosomiasis were studied by ELISA techniques. False positive reactions occurred in 10% of cases with fascioliasis and heterophyiasis respectively when using schistosomal SEA. Using Fasciola crude antigen, false positive reaction occurred in 25% of cases with schistosomiasis and 35% with heterophyiasis. The specificity of SEA in heterologous cases was 87% while that of Fasciola antigen was 70%. This difference was found to be statistically significant.

Comparative study between latex agglutination and indirect immunofluorescent antibody tests in diagnosis of toxoplasmosis.

The latex agglutination test (Toxolatex) was compared with the indirect immunofluorescent antibody test (IFAT) in investigating one hundred and fifty human sera. Both techniques showed 90.7% agreement. The mean titre of each test was significantly higher in cases with fever or lymphadenopathy than cases without these manifestations. It was concluded that the latex test provides a rapid and simple test in toxoplasmosis that can be used to exclude negative cases as nearly no false negative results were obtained. However, positive cases by latex agglutination should be confirmed and quantitated by another standardized technique.

The effect of some drugs on acute toxoplasmosis in mice.

The effect of some chemotherapeutics, on the course of acute toxoplasmosis in experimentally infected mice was studied. Obtained results showed that, praziquantel, levamisole had no effect on acute toxoplasmosis, while trimethoprim-sulphamethoxazole and clindamycin showed some prophylactic effect on acute toxoplasmosis in mice.

Effect of some anthelmintics on Hymenolepis nana in albino mice.

Mebendazole and emetine (orally and parenterally) were used to treat mice infected with H. nana. Yomesan, in a single oral dose, was also used as a standardized well-known cesticidal drug. Emetine had a marked effect on cysticercoids leading to highly significant reduction in their number. Also, it caused complete removal of adult worms in infected mice. Mebendazole had no effect on the cysticercoid stage, but it caused significant reduction in the number of adult worms. Yomesan, showed a marked lethal effect on both the cysticercoids and adult worms leading to highly significant reduction in their number.

Effect of ambient temperature changes on chronic toxoplasmosis in rats.

The effect of excess heat and cold on chronic toxoplasmosis was studied on rats. That was evident from the average increase in body weight, the effect on blood picture, deleterious effect of the pathology recorded in various organs, increased Toxoplasma brain cyst count, long persistence of parasites in the viscera, high antibody titre by I.H.A.T. in infected animals exposed to excess heat and its decrease in animals exposed to excess cold.

Effect of diet on experimental giardiasis.

Protein and fat deficiency diet produced significant reduction of Giardia cysts in rats, while vitamin A, D and iron deficiency diet had no effect on cyst count. On the other hand pathological changes due to Giardia infection encountered in small intestine and liver were aggravated by the diet deficiency induced.

Toxoplasmosis among cases of chronic tonsillitis.

One hundred cases aged 4-20 years and suffering from chronic tonsillitis were examined for Toxoplasma antibodies using indirect immunofluorescent test (IFAT). It was found that 37% of them were positive for toxoplasmosis. 41.5% of hypertrophic cases and 32% of atrophic ones had toxoplasmosis but the difference was statistically insignificant. The mean antibody titres were higher in both atrophic and hypertrophic cases than in the control group. The patients aged from 11-20 years had a higher titre of Toxoplasma antibodies than those aged below ten years. Trials to detect tachyzoites, cysts or pseudocysts in fixed paraffin sections using Hx & E, PAS or Giemsa stains were not successful. The histopathological picture of tonsils removed from positive cases of toxoplasmosis showed characteristics of toxoplasmic lymphadenitis.

Biological and haematological changes in experimental cryptosporidiosis.

In experimentally infected laboratory-bred white rats, Cryptosporidium infection rate was higher among immunosuppressed (75%) than immunocompetent ones (37.5%) with statistically insignificant difference. Cryptosporidiosis was found to be a fatal disease especially in immunosuppressed rats (50%). There was also marked flourishing of the infection as revealed by high intensity of infection in immunosuppressed than the immunocompetent rats (363 and 82.7 oocysts/pellet respectively). In spite of the severe disease, cyclophosphamide appeared to have no effect on the prepatent period. In both immunosuppressed and immunocompetent infected rats, there was a decrease in the total leucocytic count with marked lymphocytopaenia. This indicates decreased resistance to infection, thus higher oocyst counts in the pellets.