Frequency of Toxocara Antibodies in Patients Clinically Suspected to Ocular Toxocariasis, Northeast of Iran.

BACKGROUND: Human toxocariasis is a neglected parasitic disease in most countries including Iran. Among different clinical forms of toxocariasis, ocular toxocariasis (OT) is an important disease resulting in severe vision loss. However, the prevalence and incidence of OT are currently unclear in Iran. This study aimed to determine the prevalence of ocular toxocariasis among patients with uveitis in the Northeast of Iran. METHODS: From 2015 to 2017, 510 patients with uveitis referred to Khatam-al-Anbia, a tertiary eye hospital at Mashhad, Iran were examined for OT. Serum samples of the suspected patients were obtained and evaluated for IgG against Toxocara canis using ELISA test. Anti-Toxocara IgG positive serums were further investigated using confirmatory Western blotting (WB) analysis. RESULTS: Twenty patients had pathologic changes and clinical presentations in the anterior and posterior segments of their eyes and they were clinically diagnosed ocular toxocariasis. Among the 20 patients, 2 (10%) patients showed IgG antibody against Toxocara canis on ELISA as well as on WB test. The calculated prevalence of ocular toxocariasis was about 0.4%. CONCLUSION: Ocular toxocariasis can be diagnosed both clinically and serologically in Mashhad, northeastern Iran. Although OT is a rare pathologic eye disease, it should be considered as one of the important cause of infectious posterior uveitis.

Changes in the Epidemiology of Cutaneous Leishmaniasis in Northeastern Iran

The province of Khorasan-Razavi in the North East of Iran is an endemic area for anthroponotic cutaneous leishmaniasis (ACL caused mainly by Leishmania tropica) and zoonotic cutaneous leishmaniasis (ZCL caused mainly by Leishmania major). Based on clinical signs, some cities were considered as ACL foci while others were considered to be endemic for ZCL. This paper reviews studies performed on patients diagnosed with cutaneous leishmaniasis (CL) via the use of direct slide examination, ELISA, electrophoresis isoenzyme, RAPD PCR and PCR in Mashhad; the study also includes cases of CL in other cities of the Khorasan-Razavi province where only PCR used as a diagnostic tool. The data show that both Leishmania tropica and Leishmania major caused CL in most of the cities investigated. Our review shows that Leishmania major was found in areas where ACL is prevalent and Leishmania tropica was observed in areas with high incidence of ZCL. This distribution represents a major change in the epidemiological pattern of Leishmania in the Khorasan-Razavi province.

In Vitro and In Vivo Effectiveness of Carvacrol, Thymol and Linalool against Leishmania infantum.

BACKGROUND: One of the most important causative agents of visceral leishmaniasis (VL) is Leishmania infantum, which is mainly spread by Phlebotomus and Lutzomyia sandflies in the Old and New World, respectively. Novel and effective drugs to manage this neglected vector-borne disease are urgently required. In this study, we evaluated the toxicity of carvacrol, thymol and linalool, three common essential oil constituents, on amastigotes and promastigotes of L. infantum. Methods: in vitro experiments were performed by 24 h MTT assay. Carvacrol, thymol and linalool at concentrations ranging from 1.3 to 10 µg/mL were tested on promastigotes of L. infantum. For in vivo test, two groups of hamsters (Mesocricetus auratus) received 100 mg/kg of body weight/day of carvacrol and thymol as intraperitoneal injection on day 7 post-infection, followed by a 48 h later injection. The third group was treated with the glucantime as standard drug (500 mg/kg) and the last group (control) just received normal saline. On the 16th day, the number of parasites and histopathological changes in liver and spleen were investigated. RESULTS: 24 h MTT assay showed promising antileishmanial activity of thymol and carvacrol, with IC50 values of 7.2 (48 µM) and 9.8 µg/mL (65 µM), respectively. Linalool at all concentrations did not affect L. infantum promastigote viability. In vivo toxicity data of carvacrol and thymol showed that the former at 100 mg/kg was the safest and most effective treatment with little side effects on the liver. CONCLUSIONS: Overall, thymol and carvacrol are highly promising candidates for the development of effective and safe drugs in the fight against VL.

Emergence of co-infection of visceral leishmaniasis in HIV-positive patients in northeast Iran: a preliminary study.

Visceral leishmaniasis (VL) serosurvey was carried out on 49 HIV/AIDS patients among 500 asymptomatic HIV/infected patients who registered in the Khorasan Razavi Province during the last 14 years. HIV infections were detected by ELISA and confirmed using western blot assay at the AIDS centre of the Khorasan Razavi Province. All collected sera were screened using the direct agglutination test (DAT). The sera with anti-Leishmania infantum antibodies at a titre of 1:100 were considered positive for VL infection and serum titration was performed from 1:100 to 1:102,400. Nine (18.4%) patients were sero-positive according to DAT. The distribution of sera titrations were as follows: 1:100 (n = 6) 1:1600 (n = 1); 1:25,600 (n = 1) and 1:102,400 (n = 1). All sero-positive cases showed clinical signs and symptoms. The most predominant signs and symptoms of co-infection of visceral leishmaniasis in HIV-positive patients were pneumonia (n = 2), hepatosplenomegaly (n = 2), lymphadenopathy (n = 2), anaemia (n = 1), prolonged fever (n = 1) and cachexia (n = 1). Our finding shows that VL (or kala-azar) is an opportunistic disease in HIV-positive patients that may be occurred in VL endemic areas of Iran.