Comparison of serum antibody responses to Giardia lamblia of symptomatic and asymptomatic patients.

The circulating anti-parasite antibody response against Giardia lamblia in symptomatic and asymptomatic Egyptian children with confirmed giardiasis was examined. Symptomatic patients were identified using the following criteria: presence of only G. lamblia cysts in the feces, and one or more of the following symptoms, diarrhea, abdominal pain, loss of weight, vomiting and/or nausea, and abdominal distention. The anti-parasite humoral response was measured using indirect immunofluorescence (IFA), ELISA, and immunoblotting. There was a significant difference in the anti-parasite antibody response measured by IFA of asymptomatic and symptomatic patients, in which more than 34% of the asymptomatic patients had a titer equal to or less than 1:500, and more that 29% of the symptomatic patients had a titer of 1:8,000 or higher. The circulating anti-parasite total IgM and IgA but not IgG, measured by ELISA, was significantly higher in symptomatic than in asymptomatic patients, and were related to higher cyst output observed in symptomatic individuals. Although total anti-parasite IgG response was similar in symptomatic and asymptomatic patients, the analysis of the IgG isotype responses revealed that both IgG1 and IgG3 were significantly higher in symptomatic patients. The antigen recognition by anti-parasite IgM, IgA, IgG1, and IgG3 of symptomatic and asymptomatic individuals, determined by immunoblotting, was heterogeneous and revealed only minor differences in the response of the two groups.

Natural Leishmania infections in two stray dogs and two Gerbillus pyramidum in Dakahlia Governorate, Egypt.

In Egypt, zoonotic cutaneaus leishmaniasis (ZCL) and infantile visceral leishmaniasis (I.VL.) have been documented. Recently, in Dakahlia Governorate, three cases of indigenously acquired leishmaniasis (two VL. and one ZCL) have been reported. This paper aimed to search for the animal reservoir (s) of these two types of zoonotic leishmaniasis. Commensal and wild rodents as well as stray dogs were collected from concerned areas. Their role as animal reservoirs were investigated parasitologically (dogs and rodents) and serologically (rodents). Seropositivities as measured by the indirect haemagglutination tests were detected in six Rattus norvegicus (up to 1/256), two Acomys c. cahirinus (up to 1/128) and four Gerbillus pyramidum (up to 1/1024). However, Leishmania parasites were demonstrated as amastigotes (smear) and promastigotes (culture) in only two G. pyramidum. On the other hand, amastigotes of Leishmania parasites were demonstrated in splenic smears of two stray dogs, one from Bilkas Center and one from Dikarnis Center. Cultures of the splenic materials of dogs were not successful. The results indicated high probability for the presence of at least one focus of cutaneous leishmaniasis and one focus of visceral leishmaniasis. It is concluded that visceral leishmaniasis must be in mind when dealing with fever of obscure origin with hypersplenism or other suggestive manifestations.