Identification of a Cyclospora cayetanensis Oocyst Antigens and Their Validity in the Detection of Immunogenic Patterns of Cyclosporiasis Patients.

INTRODUCTION: The diagnosis of cyclosporiasis is currently based on the microscopic detection of oocysts, which may provide invalid results. The availability of simple, objective immunological screening tests would facilitate epidemiological studies of cyclosporiasis. Therefore, the present study aimed to identify the antigens of Cyclospora cayetanensis oocysts and their validity in serodiagnosis. METHODS: According to parasitological and molecular diagnoses, three study groups were specified. Group (G) I included 30 patients with cyclosporiasis, GII included 12 patients with other parasitic infections, and GIII included 16 healthy subjects. SDS-PAGE was used to analyse C. cayetanensis antigens, and the validity of western blotting and enzyme-linked immunosorbent assays (ELISAs) was then assessed amongst the sera of all study groups. RESULTS: The C. cayetanensis antigenic profile showed eight characteristic bands with molecular weights ranging from 14 to 175 kDa. Western blot analysis of sera revealed 93.3% (28/30 of GI) and 92.8% (26/28 of GII and III) sensitivity and specificity, respectively, dividing the patients in GI into four subgroups. The most frequent diagnostic bands (71.4% of GI sera) showed weights of 26-28 kDa, followed by 71 kDa (53.6%). ELISA sensitivity was 90% (27/30), and specificity was 78.6%. Validation showed perfect agreement between the PCR and western blot results, and ELISA presented substantial agreement with both the PCR and western blot results. CONCLUSIONS: Our findings suggest the existence of high immunogenic diversity in C. cayetanensis and indicate that the 26-28 kDa immunogenic groups may potentially be used as a diagnostic marker of cyclosporiasis. Due to the high validity of ELISA, it might be the test of choice for the routine serodiagnosis of cyclosporiasis.

Molecular characterization of double-stranded RNA virus in Trichomonas vaginalis Egyptian isolates and its association with pathogenicity.

Trichomoniasis is a common human sexually transmitted infection caused by Trichomonas vaginalis. The parasite can be infected with double-stranded RNA viruses (TVV). This viral infection may have important implications on trichomonal virulence and disease pathogenesis. This study aimed to determine the prevalence of T. vaginalis virus among isolates obtained from infected (symptomatic and asymptomatic) women in Ismailia City, Egypt, and to correlate the virus-infected isolates with the clinical manifestations of patients. In addition, the pathogenicity of TVV infected isolates on mice was also evaluated. T. vaginalis isolates were obtained from symptomatic and asymptomatic female patients followed by axenic cultivation in Diamond's TYM medium. The presence of T. vaginalis virus was determined from total extraction of nucleic acids (DNA-RNA) followed by reverse transcriptase-PCR. Representative samples were inoculated intraperitoneally in female albino/BALB mice to assess the pathogenicity of different isolates. A total of 110 women were examined; 40 (36.3 %) samples were positive for T. vaginalis infection. Of these 40 isolates, 8 (20 %) were infected by TVV. Five isolates contained TVV-2 virus species, and the remaining three isolates were infected withTVV-4 variant. A significant association was found between the presence of TVV and particular clinical manifestations of trichomoniasis. Experimental mice infection showed varying degrees of pathogenicity. This is the first report on T. vaginalis infection by TVV in Egypt. The strong association detected between TVV and particular clinical features of trichomoniasis and also the degree of pathogenicity in experimentally infected mice may indicate a possible clinical significance of TVV infection of T. vaginalis isolates.

IN VITRO ANTI-PROTOZOAL ACTIVITY OF PROPOLIS EXTRACT AND CYSTEINE PROTEASES INHIBITOR (PHENYL VINYL SULFONE) ON BLASTOCYSTIS SPECIES.

Blastocystis is one of the commonest enteric protozoan parasites worldwide. Despite its controversial clinical significance, frequent association with symptoms has necessitated treatment of cases with persistent symptoms. For long time, metronidzole (MTZ) was considered as a basic drug for blastocystosis treatment, however reports of treatment failure as well as its well-known side effects has promoted the search for more safe and effective alternatives. In vitro antiprotozoal activity of ethanolic extract of Egyptian propolis and a cysteine protease inhibitor, phenyl vinyl sulfone (PVS) on Blastocystis spp. was assessed through challenging with graded concentrations of propolis extract (125, 250, 500 & 1000pg/ml) and PVS (100, 200 and 300 ptg/ml) compared to MTZ (10, 50 and 100 pg/ml) and viable parasites were counted after 24, 48 and 72 hr. of incubation. Molecular subtyling of Blastocystis spp. was done using subtype specific sequence-tagged site (STS) primers. Propolis extract inhibited the growth of Blastocystis spp. in both of the detected subtypes (STI and ST3), which was especially observed in cultures exposed to 500 & 1000 µg/ml through all incuba- tion periods with the later concentration producing comparable results to MTZ. While PVS showed significant parasite count reduction on ST3 isolates, especially with the highest concentration, however the effect on STl isolate was nonsignificant. These findings highlight the potential antiprotozoal activity of propolis extract as a potent natural alternative for MTZ in treatment of blastocystosis.

Study of the pathogenic potential of Dientamoeba fragilis in experimentally infected mice.

Dientamoebafragilis (D. fragilis) is a protozoan parasite whose pathogenic potential is still disputable. The aim of this study was to illustrate the pathogenicity of D. fragilis infection and to determine the infective dose for experimental mice infection. Three groups of mice (8/each) were orally inoculated with in vitro cultured D. fragilis. The infected groups (G1- G3) received 103, 105 and 4 × 106D. fragilis/0.5 ml culture, respectively. A control group (G4) only received parasite-free culture. Two weeks post-inoculation all mice were euthanized for histopathological examination. All mice of G3 (100%) and three mice of G2 (37.5%) were infected, and the results were confirmed by PCR and different staining methods. On the other hand, all mice from group G1 showed a completely negative result. Histopathological examination of the colon and caecum of the highly infected group G3 showed active colitis, with infiltration of mixed inflammatory cells such as eosinophils, neutrophils and lymphocytes within the lamina propria of the intestinal wall. The parasite was not invading the colonic mucosa. This study revealed that infection with D. fragilis is dose-dependent. Moreover, a dose of 105D. fragilis/mouse or higher is necessary to infect mice through the oral route. In addition, this route of infection, although non-invasive, can induce severe inflammatory changes to the colonic and caecal mucosa in experimentally infected mice.

Seroepidemiology of Toxoplasma gondii amongst Pregnant Women in Jazan Province, Saudi Arabia.

Background. Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite of worldwide distribution. There is limited information about the seroprevalence of toxoplasmosis in the southern area of Saudi Arabia. The current study was carried out to determine the prevalence of T. gondii in pregnant women in Jazan province. Materials and Methods. The study was conducted between January and June 2013 and included 195 pregnant women, data on sociodemographic and predisposing factors were collected from each participant. Venous blood samples were collected following standard operating procedures. Serological analysis for latent toxoplasmosis (levels of IgG) and active toxoplasmosis (IgM) was done using Enzyme Linked Immunosorbent Assay (ELISA). Results. The overall seroprevalence of T. gondii in the study area was 24.1%. The seroprevalence of anti-Toxoplasma IgG was 20% (39 out of 195), whereas IgM seropositivity was 6.2% (12 out of 195). Only 4 pregnant women tested positive for both IgG and IgM. The highest IgG and IgM seroprevalence was among the study participants aged 35 to 39 years (13.5% and 35.1%, resp.). The seropositivity rate of T. gondii-specific antibodies was higher among pregnant women from the urban areas than those from rural communities (7.4% versus 0% and 21% versus 15.4% for IgM and IgG, resp.). Conclusions. The seroprevalence of T. gondii was high in pregnant woman in Jazan. The prevalence of toxoplasmosis increases with increase of age. Awareness health education program in Jazan needs to be maintained and developed to targeted pregnant women.

Comparison between Trichmonas vaginalis symptomatic and asymptomatic isolates effects in intravaginally infected rats.

In this study, histopathological and immunohistochemical changes of the posterior vaginal fornix's and upper portion of the vagina were compared on rats infected with symptomatic and asymptomatic human isolates. Eighteen symptomatic and asymptomatic female isolates were used (nine/ each). Two groups of infected female rats were included in this study (3 rats /isolate). The results showed that there were no differences between symptomatic and asymptomatic isolates in histopathological changes; T. vaginalis of both isolates adhered to PAS epithelial cells at the surface and traversed under these cells. Both isolates were PAS and cathepsn D positive. By scanning electron microscopy many of T. vaginalis of the isolates adhered to microvilli of the epithelium cells in the same manner. Transmission electron microscopy proved that both isolates used the pseudopodia to adhere to the vagina upper part cells. The experimental infections did not differentiate between symptomatic and asymptomatic human isolates regarding histopathological and immunohistochemical changes.

Prevalence and clinical features of Dientamoeba fragilis infections in patients suspected to have intestinal parasitic infection.

The present study was conducted to determine the prevalence and clinical features of dientamoebiasis in patients presumed to be infected with intestinal parasites. A total of 168 patients were examined for D. fragilis using microscopy (after Wheatley's trichrome staining) and culture (using modified Boeck and Drbohlav's medium). D. fragilis trophozoites were detected in 15 samples (8.9%) examined using trichrome staining and in 50 samples (29.8%) by culture method. Other enteric parasites were common in the study population as 48.8% of patients (82/168) were found harboring intestinal parasites. Blastocystis hominis was the most common, identified in 33.3% (56/168) of the samples. Giardia lamblia was detected in 17.9% (30/168) and E. histolytica/E. dispar in 11.9% (20/168). The symptoms most frequently encountered were diarrhea, abdominal pain and weight loss and fatigue. Diarrhea and abdominal pain were significantly more frequent in patients with dientamoebiasis compared to non pathogenic cases (P < 0.05). Diarrhea was 38.5% of patients infected with D. fragilis compared to 50% of patients infected with G. lamblia, while abdominal pain was encountered with D. fragilis in 41% compared to 33.3% with G. lamblia. These differences were insignificant (P > 0.05).

Cervical intraepithelial neoplasia (CIN) and Trichomonas vaginalis infection as revealed by polymerase chain reaction.

The impact of sexually transmitted diseases (STDs) on the development of cervical intraepithelial neoplasia (CIN) has been increasingly recognized over the last 25 years. The role of bacterial vaginosis (BV) is the focus of several current investigations, not only in the genesis of CIN but also in the development of other gynecological and obstetric complications. Out of 150 women with vaginitis, 46 were diagnosed as T. vaginalis infection by different methods: wet mount, In-Pouch TV culture and PCR. Pap smear showed that 10 smears had atypical squamous cells of undetermined significance (ASCUS), 2 smears had atypical squamous cells of high grade (ASC-H), 8 smears had squamous intraepithelial lesions of low-grade (SIL-L) in the form of mild dysplasia, 4 smears showed squamous intraepithelial lesions of high-grade (SIL-H) in the form of moderate to severe dysplasia and carcinoma in-situ. So, the early detection and treatment of symptomatic and asymptomatic trichomoniasis minimize the complications of cervical neoplasia.