Secretory and humoral antibody responses to Blastocystis hominis in symptomatic and asymptomatic human infections.

The study included 3 groups of individuals, in the first 2 groups they had positive stool microscopic examinations only for B. hominis indicating blastocystosis, with and without gastrointestinal symptoms, respectively, while the last group included apparently healthy individuals with no parasites in stool. Stool and serum samples of these individuals were subjected to detection of anti-B. hominis fecal and serum IgA and serum IgG antibodies by indirect ELISA, and detection of B. hominis fecal and serum antigens by double sandwich ELISA. In symptomatic B. hominis infections with positive stool microscopy the study recorded first: specific secretory IgA and humoral IgA and IgG antibody responses at a prevalence of 100%, 83.3% and 86.6%, respectively, with an increased significant difference (P<0.001) of each from healthy controls, together with an increase in level of secretory IgA than that of humoral IgA antibody (P<0.001), and second: the presence of specific antigens in stool and serum at a prevalence of 96.6% and 90%, respectively. With an increased significant difference (P<0.001) of each from healthy controls together with the former at a higher level than the latter (P<0.05). In asymptomatic B. hominis infections with positive stool microscopy the study recorded first; absence of each of the studied specific secretory and humoral antibody responses with no significant difference (P>0.05) of each from healthy controls, and second; absence of specific antigens in stool and serum with no significant difference (P>0.05) of each from healthy controls nor from each other. The explanations and implications of these results are discussed.

Cellular immune response in giardiasis.

There was statistically significant difference between all groups of giardiasis patients regarding the grade of CD4 lymphocyte infiltration (P<0.001), being more marked in symptomatic group. The prevalence of flatulence, anorexia and vomiting were more frequent in patients with heavy CD4 lymphocyte infiltration in duodenum. A high statistical significant increase was in the mean OD values of anti-Giardia duodenal secretory IgA in patients with marked CD4 infiltration in duodenum. But, a statistical insignificant difference in mean OD values of anti-Giardia total serum Ig in patients with different grades of CD4 infiltration in symptomatic group. There was statistically significant increased in the mean OD values of anti-Giardia total serum Ig in patients with marked intraepithelial CD8 lymphocyte Infiltration in the duodenum In the asymptomatic group, there was statistically insignificant difference in the mean OD values of anti-Giardia total serum Ig in patients with different grade of intra-epithelial CD8 infiltration in symptomatic group. There is statistically significant increased in the mean OD values of anti-Giardia total serum Ig in patients with marked intra-epithelial CD8 lymphocyte infiltration in the duodenum regarding immunohistochemical staining of Giardia antigen in duodenal biopsies. All the 61 symptomatic giardiasis patients revealed Giardia antigen stains in their duodenal biopsies with a sensitivity of 100% while asymptomatic group a sensitivity of 93.181%. None in the controls showed positive Giardia antigen in the duodenal biopsies with 100% specificity.

Cytogenetics of acute and chronic schistosomiasis mansoni.

Schistosomiasis mansoni patients with acute were examined for genetic damage using the conventional cytogenetic method to assess the frequency of chromosomal aberration (CA) in the cultured blood cells. A non-significant difference was noticed in the frequency of CA between patients (acute & chronic) and control (n = 15), but on treatment of blood cultures with bleomycin (a radiomimetic agent with a DNA alkylating effect), the percentage of induced breakage and fragmentation increased significantly 2 and 3 folds in acute and chronic patients respectively, indicating increased chromosomal fragility. The incidence of rearrangement in the form of translocation increased significantly as compared to control blood cultures treated with bleomycin. The study revealed the antimitotic of schistosomiasis from significant inhibition of mitotic index. Although schistosomiasis did not show a direct clastogenic effect, it can be considered as a comutagen when there is concomitant exposure, especially chronic ones, to radiomimetic agents, schistosomiasis may amplify their cytogenetic damage.

A patient with intestinal amoebiasis and cutaneous amoebic ulcer.

This paper reports a patient with intestinal amoebiasis in concomitant with amoebic ulcer in the thigh. The ulcer was suspected to be carcinoma, complicated cutaneous leishmaniasis or due to free-living amoebae. The diagnosis was confirmed by the pathological and parasitological demonstration of haematophagous trophozoites of E. histolytica. The patient was successfully treated with Metronidazole.

The use of Ziehl-Neelsen stain, enzyme-linked immunosorbent assay and nested polymerase chain reaction in diagnosis of cryptosporidiosis in immuno-competent, -compromised patients.

In the present study, Cryptosporidium parvum was diagnosed in stool by Z-N stain, ELISA and PCR. The detected cases were 5.3%, 8.3% and 9.6% by the previous three methods, respectively. The sensitivity, specificity and accuracy of the different techniques were evaluated. The Z-N stain showed the lowest sensitivity and accuracy in relation to either ELISA or PCR. Moreover, the study revealed that the sensitivity, specificity and accuracy of ELISA detection of Cryptosporidium in relation to detection of DNA in stool by PCR were 84.2%, 96% and 88.8%, respectively. Consequently, PCR showed the best results. From a practical point of view, ELISA is recommended for wide spread use in diagnosis of cryptosporidiosis.

The red fox, Vulpes v. aegyptiaca, a new host of leishmania major in Sinai Peninsula.

A leishmanial isolate was obtained from the ear of one red fox or Nile fox (Vulpes v. aegyptiaca) out of eight from North Sinai Governorate. The isolate was typed by the enzymatic variant profiles of the four enzymes, GPI, G6PD. 6PGD and PGM against the three Old World reference strains, L. major, L. tropica and L. donovani and proved to be Leishmania major. This is the second time that L. major has been shown to occur in canine hosts. The list of the mammalian hosts of L. major was reviewed and discussed.

Vascular endothelial growth factor level in chronic liver diseases.

Ninety individuals (76 males and 14 females) were classified into four groups. G1 (Control) included 20 healthy individuals. G2 (Chronic hepatitis) included 20 patients, G3 (Liver cirrhosis group) included 30 patients, and G4 (HCC) included 20 patients with HCC. All groups were subjected to clinical examination, abdominal ultrasonography, complete blood picture, HCV antibodies, HBs Ag, and function tests (total and direct bilirubin, total plasma proteins and albumin, prothrombin time and concentration, and liver enzymes AST, ALT and ALP). Patients of G3 & 4 were classified according to Child-Pugh classification into A. B and C. Upper endoscopic examination was done for 36/50 patients with chronic hepatitis or HCC. Circulating VEGF levels were determined by ELISA. There was a statistically high significant levels of circulating VEGF in G1, 2 & 3 than in the controls. A statistically significant higher level of circulating VEGF in G4 than in G3 & G4, and a statistically negative significant between VEGF levels and platelet count in G2. No significant correlation between VEGF and the grade of esophageal varices in G3 & G4. and no significant correlation between VEGF and upper GIT bleeding or spider naevi (vascular skin changes) in G2. A statistically significant was in correlation between VEGF and degree of hepatic dysfunction.