ABSTRACT
ELISA has become the mainstay for clinical serologic evaluation of toxoplasmosis. One of the major obstacles encountered in the evaluation of ELISA is the false-positive results due to immunological cross-reactions with other parasitic diseases that exhibit some lack of specificity. Evaluation of the diagnostic efficacy of two ELISA techniques: Cystatin capture ELISA and sodium metaperiodate treated antigen-ELISA [SMP-ELISA] compared to conventional ELISA, to detect IgG antibodies for crude T. gondii antigen in sera of toxoplasmosis patients. The study was carried out on 50 individuals categorized into three groups. Toxoplasmosis group included 30 patients confirmed by Sabin-Feldman dye test. Other parasitic diseases group included 10 sera from patients with amoebiasis [2], fascioliasis [2], hydatidosis [3] and schistosomiasis [3]. Control group included 10 healthy individuals. All sera under study were examined for the detection of T gondii IgG by three different ELISA techniques: Cystatin capture ELISA, SMP-ELISA amid conventional ELISA. The diagnostic performance of the three tests was statistically compared. Cystatin capture ELISA gave the best diagnostic results with 96.6% sensitivity, 95% specificity, 96.6% Positive Predictive Value [PPV], 95% Negative Predictive Value [NPV] and 96% diagnostic accuracy. In spite of the lower sensitivity and NPV of SMP-ELISA [86.6% and 82.6%, respectively] than the conventional ELISA, it had higher specificity [95%] and PPV [96.3%]. Cystatin capture ELISA improved the diagnostic performance of conventional ELISA in diagnosis of human toxoplasmosis
Subject(s)
Humans , Enzyme-Linked Immunosorbent Assay/methods , Serologic Tests/methods , Sensitivity and SpecificityABSTRACT
Physiological hormones modulate immune responses and implicate in associated susceptibilities to infections. To clarify these endocrinological effects, the influence of estrogen and thyroid deficiency, due to ovariectomy and thyroidectomy, respectively, on course and outcome of Trichinella spiralis infection in rats was studied. While in ovariectomized rats there was significant increase in both adult and muscle larval counts as compared to intact infected rats, in thyroidectomized rats there was a significant increase in larval but not in adult count. Combined ovariectomy and thyroidectomy resulted in significant increase in both adult and larval counts. Serum CPK and blood glucose were significantly elevated in ovariectomized and/or thyroidectomized rats as compared to intact infected one. The deficiency of female sex hormones, and/or thyroid hormones in T. spiralis infected rats affected the host resistance to infection by increasing parasite burden influencing the course and outcome of parasitic infection
Subject(s)
Female , Animals, Laboratory , Trichinella spiralis , Thyroidectomy , Ovariectomy , Rats , Models, Animal , Creatine Kinase , Blood Glucose , Thyroid Hormones , Gonadal Steroid HormonesABSTRACT
Experimental duel infection with S.mansoni and E. granulosus was induced in mice to determine their effect on serum nitric oxide [NO] level and accordingly on the sequences of histopathological lesions affecting the liver. The results showed that serum NO level was significantly increased [p = 0.05] in mice infected with both parasites [GI] in comparison to either S.mansoni [GIV] or E. granulosus [GV]. The NO elevation on hepatic pathological lesions of both diseases showed a marked reduction of granuloma size with absence of concentric fibrosis in GI as early as 4 weeks of concomitant infection as compared to GIV. In spite of the significant increase of NO level when E. granulosus infection induced in late stages of schistosomiasis [GsII and III], yet granuloma size was not suppressed. Also, there was absence or death of hydatid cyst in mice [GI] compared to E. granulosus [GV]. So, the duel infection with the two parasites affected serum NO level and hepatic hisotopahtology, by ameliorative or deteriorative effects, according to duration of infection with either
Subject(s)
Animals, Laboratory , Echinococcosis/complications , Liver/pathology , Histology , Nitric Oxide/blood , MiceABSTRACT
Fresh, frozen-thawed and formalin-preserved muscle samples heavily infected with Trichinella larvae were cut into several pieces and stained with Giemsa and Leishman and the reference Haematoxylineosin [H and E] stain. Observation under microscope revealed that both muscle larvae and nurse cells in fresh and formalin preserved specimens appeared as purplish blue structures contrasting with the pinkish color of non-infected muscle fibers in both Giemsa and Leishman stains. These findings were confirmed in H and E stained samples. However, frozen samples did not show contrast stain