Comparison between elisa and various stains techniques in laboratory diagnosis of cryptosporidiosis

Cryptosporidium spp. is an important parasitic protozoa causing diarrhea which is a severe life-threatening diarrhea especially in immunocompromised hosts. We aimed to evaluate the usefulness of detection of Cryptosporidium spp. copro-antigen from fecal specimens by using enzyme linked immunosorbent assay [ELISA] test and comparing its sensitivity and specificity with some staining methods. The results revealed that Modified Acid-Fast stain is considered better than Giemsa in detecting Cryptosporidium species oocysts in faecal smears as their sensitivity were 67.5% and 53.75% respectively. On contrary, ELISA technique is considered the best method used for detection of cryptosporidial infection as its sensitivity is 90%

Modulation of haematological and pathological changes caused by toxoplasma gondii in an experimental model of chronic infection

Wide spectrum of pathologic patterns is encountered in T. gondii infection, ranging from trivial pathology to fatal disease. The study was done to evaluate the ability of some drug groups to reverse the pathological changes caused by T. gondii infection. This evaluation was done, in vivo, in a rat model of chronic infection parallel to that in human. Lung, liver and brain specimens were taken in definite time points respecting the kinetics of infection in that model. Blood counts were done to all groups to evaluate efficacy and toxicity of drugs. A new combination of dipyridamole/ allopurinol was able to significantly reduce the pathology in all organs to almost the baseline pathology of chronic Toxoplasma infection. The relatively moderate protective effect of pyrimethamine/sulfadiazine combination was undermined by the toxic effects evidenced by pathology and haematological parameters. Spiramycin, in spite of proving safe, yet its protective effective is relatively weak in all organs especially in the brain where it seems to offer no protection

New effective and safe combination therapy for acute and chronic toxoplasmosis in murine models

Toxoplasma gondii is a protozoan parasite that infects humans and most species of warm blood animals. The most effective treatment for toxoplasmosis is the classic combination of pyrimethamine/sulfadiazine while the safest drug is spiramycin. These traditional anti-Toxoplasma drugs are either ineffective or have serious side effects that sometimes needs discontinuation of treatment. Both mouse [acute] and rat [chronic] models were used to evaluate a novel dipyridamole/allopurinol anti-Toxoplasma combination therapy that targets the purine salvage pathways of the parasite. The efficacy and safety of the new drugs were evaluated in comparison with traditional therapies; pyrimethamine/sulfadiazine and spiramycin. The life expectancy of mice in dipyridamole/ allopurinol group was significantly increased in comparison to other drug groups and almost doubled in relation to the infection control group. A significant reduction of anti-Toxoplasma antibody titers was only present in dipyridamole/allopurinol group in comparison to the infection control groups in both acute and chronic states of infection. The drug proves to be safe as evidenced by normal blood parameters reflecting no sign of drug toxicity. Pyrimethamine/sulfadiazine combination was second in efficacy while spiramycin was second in safety

Specific circulating immune complexes in sera of children infected with S. haematobium

Schistosomiasis is a major health problem in our country. This work is carried out for detection of specific circulating immune complexes [CICs] in S. haematobium infected children as a trial to evaluate their potential use in immunodiagnosis of the disease and in assessment of disease intensity and morbidity. Sixty seven Egyptian children from El-Minia and Sharkia Governorates were included in this study, 50 of them were infected with S. haematobium [active cases], 5 infected with parasites other than Schistosoma [infected control] and 12 children were parasites free [normal control]. Sera of all cases were examined to detect specific schistosomal circulating immune complexes. Indirect ELISA assay using monoclonal antibody 128C3/3/21 as a coating antibody was used. Forty seven out of fifty actively infected cases had positive circulating immune complexes level yielding a test sensitivity of 94 percent. All of the normal control group had negative CIC level yielding a test specificity of 100 percent. The level of CICs was significantly higher in heavily infected children [those excreting >50 eggs/l0ml urine] when compared with those with light infection [excreting <50 eggs/l0ml urine]. ELISA using highly purified monoclonal antibody appeared to be a specific and sensitive test for detection of schistosomal CICs level in the serum and evaluating the intensity of infection

Suppression of immunopathology in schistosomiasis by antigen-daunomycin immunoconjugate I-In vitro studies on antigen specificity and genetic restriction

Soluble Egg Antigen [SEA], is the major stimulus for immunopathological lesions [granuloma formation and fibrosis] in schistosomiasis. Antigen presenting cells and T-Iymphocytes with receptors for SEA are primarily responsible for the induction and regulation of the immunopathology through the production of cytokines. During the present work SEA was conjugated to Daunomycin [DM], a cytotoxic antibiotic of the rhodomycin group. Antigen presenting cells and T -lymphocytes bearing surface receptors for SEA bind, internalize and activate the DM. Activated DM, inhibits RNA and DNA synthesis leading to inactivation and/or death of the targeted cells. The suppression effects of the Antigen-Daunomycin [Ag-DM] were assessed in vitro. Ag-DM conjugates demonstrated significant suppression of multiple in vitro parameters that depend on cellular reactivity to a specific antigen. The parameters were Antigen Mediated Blast Transformation [AMBT], In Vitro Granuloma Formation [IVGF] and cytokine production. The Suppression was a dose dependent and antigen specific, but not genetically restricted. DM alone demonstrated severe non-specific cytotoxicity. The studies support the feasibility of using antigen specific cytotoxic immunoconjugates to limit the pathological lesions in schistosomiasis

Immunoregulation of granuloma formation and fibrosis in schistosomiasis by antigen-daunomycin immunoconjugate II-in vivo studies

Hepatic granuloma formation and fibrosis in schistosomiasis are the principle cause of morbidity. These inflammatory responses are induced and regulatd by T-Iymphocytes with receptors for soluble Egg Antigen [SEA]. These T cells are genentically heterogeneous in man. Approaches that avoid genetic restriction by directly addressing antigen and T cell interaction will be useful. During the Present work, SEA [major anti genic stimulus for immunopathology in schistosomiasis] was conjugated to Daunomycin [DM], a cytotoxic rhodamycin. The suppression effects of SEA-DM on the development of granuloma formation and fibrosis due to schistosomiasis mansoni in mice was assessed. Relative to saline treated control group, SEA-DM when administered intravenously, it specifically diminished the liver granulomata size by 65% in infected mice in response to S. mansoni eggs deposited in the liver tissue at the acute stage of the disease [6-8 weeks post-infection]. In addition, SEA-DM reduced the hepatic collagen synthesis by 64% and reduced the deposition of hepatic matrix proteins such as, isotypes I and II collagens and fibronectin. Moreover, SEA- DM suppressed the accummulation of CD[4+] cells [helper cells] within the granulomatous lesions and liver parenchyma, but had little effect on CD[8+] [suppressor cells]. DM alone resulted in 50% mortality and severe morbidity, but there was no visible mortality in the SEADM animal group

Immunodiagnosis of cryptosporidiosis in Children with chronic diarrhea in El-Menya governorate

ELISA, as well as stool analysis were used to evaluate the presence of Cryptosporidiosis in 285 suspected cases among children in El-Minia Governorate. Sera from 259 children with chronic diarrhea, 23 [8.8 percent], 7 [2.7 percent] and 5 [1.9 percent] were positive for specific IgG, IgM and IgG and IgM to Cryptosporidium respectively. Of the 259, 18 [6.9 percent] stool samples were positive for Cryptosporidium oocysts. Of the 26 asymptomatic cases, 2[7.6 percent] were positive for oocysts in their stool samples and 3 [11.5 percent] were positive for specific IgG antibodies but no one had IgM. Detection of specific IgG increased in the two to four years -old age -group. It was concluded that, serological diagnosis of Cryptosporidium infection will be useful in establishing more accurate prevalence rate

up-to-date review on the taxonomy and immunobiology of the genus cryptosporidium

Cryptosporidiosis caused by a coccidian parasite belonging to the genus Cryptosporidium is now recognized as an important cause of gastroenteritis and diarrhea in a number of mammalian hosts including man, especially in immunocompromised patients. The progressively increasing rates of infection with cryptosporidiosis in Egypt is noticeable and alarming. The present review, therefore, brings up recent information on the taxonomy, life cycle and immunobiology of different species of this parasite in a trial to enrich the knowledge on this dangerous protozoan invader

Preliminary notes on the effect of praziquantel against hymenolepis nana and giardia lamblia

Praziquantel is the most recent anti-bilharzial drug being given orally. This study is an attempt to evaluate the effect of this drug against other parasitic infections, especially Hymenolepis nana and Giardia lamblia which are common among school children in Menia Governorate. For this purpose, sixty patients harboring these parasites were selected for this trial. Forty cases of them harbored Hymenolepis nana only, ten patients harbored Giardia lamblia only, while the third group [ten patients] harbored both infection. Three schedules were applied in this trial; 20 mg/kg bw as one dose, 40 m/kg bw divided into two doses with six hours interval and 40 mg/kg bw divided into three equal doses with six hours intervals. Follow up was carried out weekly for three months duration