Diagnosis of toxoplasmosis in children with malignancy.

The study aimed at the diagnosis of toxoplasmosis in 73 children with malignancy; 31 with lymphoma (22 with Hodgkin's and 9 with non-Hodgkin's lymphoma) and 42 with leukemia (34 with acute lymphoblastic leukemia and 8 with acute myelogenic leukemia). In positive cases toxoplasmosis was manifested by any of the following; fever, lymph node enlargement, neurological manifestations and/or hepatosplenomegaly. The indirect hemagglutination test (IHA) for toxoplasmosis detected 4 (5.4%) positive cases with malignancy, 2 with Hodgkin's lymphoma, one with non-Hodgkin's lymphoma and one with acute lymphoblastic leukemia. The immunoglobulin M enzyme-linked immunosorbent assay (IgM ELISA) detected only one (1.4%) case with Hodgkin's lymphoma. Immunoglobulin G (IgG) ELISA detected 6 (8.2%) positive cases, 3 with Hodgkin's lymphoma, one with non-Hodgkin's lymphoma and 2 cases with acute lymphoblastic leukemia. Polymerase chain reaction for detection of parasite DNA in blood (PCR) was the most useful in diagnosing toxoplasmosis with malignancy, as it was able to detect 9 (12.3%) positive cases; 5 (6.8%) with Hodgkin's lymphoma, one (1.4%) with non-Hodgkin's lymphoma and 3 (4.1%) with acute lymphoblastic leukemia. No positive toxoplasmosis cases were detected with acute myelogenic leukemia by any of the above methods.

Study of gamma-interferon in schistosomiasis mansoni, autoimmune diseases and schistosomal arthropathy.

IFN-gamma, a Th1 cytokine was quantitatively estimated using EASIA in the sera of patients with different stages of schistosomiasis mansoni autoimmune diseases and schistosomal arthropathy. Level of IFN-gamma was significantly elevated in all the test groups compared to the control group. The highest level of IFN-gamma observed was in RA and SLE, with insignificant statistical difference (P > 0.05) between them. Cases with early S. mansoni infection showed significant higher level (P < 0.05) of IFN-gamma compared to hepatosplenic schistosomiasis with and without ascites. A significant statistical difference (P < 0.05) concerning IFN-gamma level was observed when comparing RA and SLE to different stages of S. mansoni infection and schistosomal arthropathy. This might lead to a conclusion that IFN-gamma estimation in sera of patients having joint complaint could be a good marker for differentiation between autoimmune collagen induced arthritis and schistosomiasis induced arthropathy.

Role of recombinent interleukin-12 as an adjuvant on vaccine-induced immunity in murine Schistosoma mansoni infection.

In the present work, the role of recombinent Interleukin-12 (rIL-12) as an adjuvant to soluble worm antigen preparation (SWAP) in protection against primary murine S. mansoni infection, using certain immunization protocol, was studied. A highly significant statistical increase in resistance (P<0.001) was observed between the group immunized with SWAP and rIL-12 (group I) and those immunized with SWAP only (group II), when each was compared to the infection control group (group III). Moreover, resistance to challenge infection was higher in group I (73.6%) than in group II (66.1%). In comparison to group III, histopathological examination of liver sections of groups I and II showed marked reduction in granuloma sizes, with more reduction in group I to the extent that some ova were seen without cellular reaction around them. Liver necrosis and fibrosis were detected only in the infection control group. In contrast to group III, sections in the small intestine did not show any granulomatous reaction in groups I and II. rIL-12, when administered with SWAP could inhibit mesangial cells proliferation in the kidney glomeruli of mice in group I. However, minimal mesangial cells proliferation was observed in the kidney sections from mice in group II, when compared to the prominent proliferation seen in group III. rIL-12 has a prominent role when administered as an adjuvant to SWAP, against primary murine S. mansoni infection and for preventing granulomatous reaction, decreasing worm burden and increasing resistance to infection.