An IFAT cercarial slide antigen preparation for schistosomiasis.

A modified technique for the preparation of a cercarial microscopic slide antigen for use in IFAT, that could be stored at -20 degrees C for 6 months is described. Cercariae were deposited by cooling, fixed in 0.5% buffered formaline, mixed with 7% egg albumin, dropped on slides and dried. Before use, antigen was post-fixed in absolute methyl alcohol. Evans blue was used as a counterstain. The antigen was evaluated with known human positive and negative sera, also with sera from normal individuals and others residing in endemic areas and exposed to infections with schistosomiasis; as well as with sera of patients with other helminthic infections (strongyloidiasis, ankylostomiasis, ascariasis and microfilariasis). It indicated a sensitivity of 83% and a specificity of 61.5%.

Evaluation of two cultural media (CPLM & TYM) for isolation and maintenance of Trichomonas vaginalis stocks in the laboratory.

Five hundreds vaginal discharge specimens were inoculated simultaneously in 2 axenic culture media (CPLM & TYM), in order to compare their ability to isolate and to maintain the growth of T. vaginalis in the laboratory. While both media were found to be equally good in detecting the organisms in vaginal discharges, yet, T. vaginalis stocks were maintained for a longer time in TYM medium (one year), than in the CPLM medium (2 weeks). The yields of the parasites with different inocula subcultured and after different incubation periods were counted in the TYM medium.

Incidence of Toxoplasma and Toxocara antibodies among out-patients in the Ophthalmic Research Institute, Egypt.

Infection by Toxoplasma gondii and Toxocara canis is getting much important nowadays. Both are soil transmitted infections. The present study was planned to detect the incidence of T. gondii and T. canis antibodies among 100 patients attending the outpatient clinics in Research Institutes of Ophthalmology (RIO), whose urine and stool were free from other parasitic stages. Patients were classified into two groups, group I; (70 ocular cases) and group II, (30 non-occular cases). Control group (group III); 30 healthy persons. Sera from all individuals were subjected to IFAT and IHAT to detect Toxoplasma antibodies and IFAT to detect Toxocara antibodies. By using IFAT for Toxoplasma revealed, 25% as a total incidence, 21.4% in group I, 33.3% in group II and 6.6% in group III. While IHAT revealed 51% as a total incidence, 51.4% in group I, 50% in group II and 23.3% in group III. Among group I, retinochoroiditis cases showed the highest incidence and titre. While hydrocephalic cases showed highest incidence and titre in group II. T. canis antibodies revealed 23% as a total incidence, 14.3% in group I, 43.3% in group II and 5% in group III. Cases presented with retinal detachment showed the highest incidence and titre in group I while in group II hepatomegalic cases gave the highest incidence and titre. Concomitant infection of both Toxoplasma and Toxocara was detected in 8% of positive cases.

Evaluation of different serological tests in mansonian schistosomiasis and correlation to hepatitis B virus infection.

A total of 70 bilharzial mansonian patients (Group I: 20 early intestinal mansonian patients, Group II: 20 hepatosplenic mansonian patients without ascites, Group III: 30 hepatosplenic mansonian patients with ascites) and 30 normal controls were studied. Using the circumoval percipitin test (COPT), there was a statistically significant difference between sensitivities in Group I and Group III with higher sensitivity for Group I. Using either the indirect haemagglutination test (IHA) or the indirect fluorescent antibody test (IFAT), there was no statistically significant difference between the sensitivities in the different bilharzial groups. No statistically significant difference was found between the 3 tests in Group I, II respectively. A statistically significant difference was found between the sensitivities of COPT and IHA in Group III. A highly significant difference was found between the sensitivities of COPT and IFAT in Group III also. No statistically significant difference was found between the sensitivities of IFAT and IHA in Group III. There was no statistically significant difference between the percentages of positivity of hepatitis B surface antigen (HBSAg) in the different bilharzial groups while each of the 3 groups showed highly statistically significant difference with the control group. No statistically significant difference was found between the positivities of HBSAg and the different titers of either IHA of IFAT in each group.

Characterization of Egyptian isolates of Trichomonas vaginalis I. Isoenzyme patterns.

Three T. vaginalis isolates from Egypt were compared for their isoenzyme electrophoretic patterns on cellulose acetate. The enzymes studied were: glucose-6-dehydrogenase (G6PD); malate dehydrogenase (MDH); phosphoglucomutase (PGM); glucose phosphate isomerase (GPI); malic enzyme (ME); hexokinase (HK) and lactate dehydrogenase (LDH). The three isolates shared the same isoenzyme banding patterns of MDH; GPI; HK and LDH. Two of these isolates were similar in their banding patterns of G6PD, PGM and different from those of the third isolate. The latter was similar to one of the two isolates and different from the other in the ME isoenzyme patterns.

Characterization of Egyptian isolates of Trichomonas vaginalis: I. Serotyping.

Antitrichomonal hyperimmune sera against T. vaginalis stocks isolated from Egyptian female patients were employed for serological differentiation of somatic and soluble antigens in the Ouchterlony gel double immunodiffusion technique. It was concluded that soluble trichomonal antigens present in association with living flagellates are stock--specific reacting with some, but not all the antitrichomonal hyperimmune sera, while those present in association with dead parasites are common antigens reacting with all the sera. Three stocks, E1, E2 and E3 could be differentiated into two strains using their stock--specific antigens. The somatic antigens of six trichomonal stocks reacted with all the hyperimmune sera denoting common antigenic make up.

Evaluation of some direct diagnostic methods in intestinal parasitic infections.

Stool specimens of 100 cases attending the outpatient clinic of Cairo Medical Center Hospital suffering from gastro-intestinal disturbances were examined for intestinal parasites by direct smear, trichrome stained smear and formol ethyl acetate concentration methods. Although formol ethyl acetate concentration method gave the best results (45%), followed by trichrome stain (37%) then direct smear (32%) yet, for a reliable diagnosis a combination of several techniques is required.