Vol 5 No 4 (2010)

Articles

  • XML | PDF | downloads: 208 | views: 309 | pages: 1-8

    Background: Leishmaniasis is one of the infectious parasitic diseases of highest incidence in the world. Cutaneous Leishmaniasis (CL) has long been reported in Shiraz, Southern Iran. There is a need to find a sensitive and specific method for treatment and control of the disease.
    Methods: We have compared the sensitivity of the conventional methods microscopy and cultiva­tion of lesion scrapes against PCR amplification of parasite kinetoplast DNA from these sam­ples. The samples (n=219) were obtained from the patients clinically suspected of CL. The smears were stained with Giemsa for microscopy and cultured in Novy-Nicolle-McNeal (NNN) blood agar for promastigote growth. For PCR, the dry smears were scraped off the slides and DNA was extracted.
    Results: The positive rates from 219 specimens were 76.71%, 50.68%, and 93.61% for micros­copy, cultivation, and PCR, respectively. The highest correlation was found between PCR and micros­copy method (P= 0.014). In PCR assay, 95.61%, 3.9%, and 0.49% of the samples were identi­fied as Leishmania major, L. tropica, and dermatropic L. infantum, respectively.
    Conclusion: The PCR method appears to be the most sensitive for the diagnosis of CL and is valu­able for identifying the other species of Leishmania with confusing dermatropic signs.

  • XML | PDF | downloads: 165 | views: 182 | pages: 9-14

    Background: Trichomoniasis is a worldwide protozoan parasitic disease and metronidazole is a choice drug for its treatment. Because of disease importance in public health and its controversial ideas about the prevalence of drug resistance, this study was carried out.

    Methods: Fifty-two suspected vaginal samples were collected from 2006 to 2007 in Gynecology Maryam Hospital, Tehran, Iran. All isolates were examined by microscopic, culture and PCR tech­niques. The PCR products were analyzed by RFLP and CSGE methods and two suspected samples were sequenced.

    Results: Trichomonas vaginalis was identified from all 52 samples. Of 52 isolates, 45 samples were successfully cultured and amplified by PCR except one. Seven were positive only by PCR. Finally, ITS1 fragment was successfully amplified in 51 of 52.  CSGE analysis and PCR products di­gestion by MspI followed by sequencing showed nucleotide mutation at position 209 (C209T) of the ITS1 fragment in two (3.9%) of them.

    Conclusion: The results showed mutation in ITS1 fragment of T. vaginalis in two (3.9%) of Ira­nian isolates which may be related to metronidazole resistance.

  • XML | PDF | downloads: 305 | views: 289 | pages: 15-20

    Background: In order to verify the infectivity of rodents with endoparasites in Germi (Dashte-Mogan, Arda­bil Province) the current study was undertaken.

    Methods: Using live traps, 177 rodents were trapped during 2005-2007. In field laboratory, all rodents were bled prior to autopsy, frozen at -20°C, and shipped to the School of Public Health, Tehran University of Medical Sciences, Iran. In parasitological laboratory, every rodent was dissected and its different or­gans were examined for the presence of any parasite. Blood thick and thin smears as well as impression smears of liver and spleen were stained with Geimsa and examined microscopically.

    Results: Two species of rodents were trapped; Meriones persicus (90.4%) and Microtus socialis (9.6%). The species of parasites found in M. persicus and their prevalences were as follows: Hymenolepis di­minuta (38.8%), Hymenolepis nana (2.5%), Trichuris sp.(40.6), Mesocestoides larva (=tetrathyridium) (3.1%), Capil­laria hepatica (6.9%), Moniliformis moniliformis (11.3%), Syphacia obvelata (2.5%), Taenia endotho­racicus larva (0.6%), Physaloptera sp. (0.6%), Dentostomella translucida (0.6%), Heligmosomum mix­tum (0.6%), Strobilocercus fasciolaris (0.6%),and Aspiculuris tetraptera (0.6%). The species of para­sites found in M. socialis and their prevalences were as follows: H. diminuta (17.6%), Trichuris sp. (5.9%), Mesocestoides larva (5.9%), S. obvelata (11.8%), S. syphacia (11.8%), H. mixtum (17.6%), and Aspiculuris tetraptera (11.8%). There were no statistical differences between male and female for infectivity with parasites in either M. persicus or M. socialis. No blood or tissue protozoan parasite was found in any of the rodents examined.  

    Conclusion: Among different species identified, some had zoonotic importance. Therefore, the potential health hazard of these species needs to be considered to prevent infectivity of humans.       

  • XML | PDF | downloads: 175 | views: 299 | pages: 21-30

    Background: Ovine babesiosis is the most important haemoparasitic tick-borne disease of small ruminants in Iran caused by Babesia ovis, B. motasi, and B. crassa. The aim of this study was to characterize the species of ovine Babesia species isolated from different geographical region of Iran.

    Methods: One hundred fifty four blood samples collected from animals, which demonstrated the pale mucous membranes or hyperthermia. The specimens were transferred to the laboratory and the blood smears stained with Geimsa, the morphological and biometrical data of parasite in any infected erythrocyte have been considered. Extracted DNA from each blood samples were used in PCR and semi nested- PCR in order to confirm the presence of the species.

    Results: The results of the PCR assays showed nine (5.85%), 81 (53%) and 18 (11.7%) were distinguished as Babesia, Theileria and mixed infection, respectively.  Semi nested- PCR did not confirm the presence of B. motasi.

    Conclusion: The causative organism of many cases of haemoprotozoal diseases, which recorded in previous studies, could be B. ovis or Theileria lestoquardi. The result confirmed that B. ovis was only species which causes babesiosis in the study areas. It seems that the biometrical polymor­phisms could exist in B. ovis in Iran. This polymorphism could be a main problem in differen­tiation between B. ovis and B. motasi and it could be dissolved by specific PCR analysis.

  • XML | PDF | downloads: 147 | views: 206 | pages: 31-36

    Background: Trichomoniasis is an extremely common sexually transmitted infection (STI) world­wide and is associated with important public health problems, including amplification of HIV transmission. This disease is in forms of symptomatic and asymptomatic in women and may de­pend on host as well as parasite variables. Most of the studies reported from females are based on examination of vaginal secretions and urine samples by direct smear and culture in modified Dia­mond's media. The aim of this study was checking the samples, which were negative by direct smear and culture, with PCR technique.

    Methods: The urine samples and vaginal discharge of patients attending Gynecology Clinics of Ma­zandaran Province, Iran with different symptoms rechecked for Trichomonas vaginalis by PCR technique using primers targeting a conserved region of the beta-tubulin genes of the para­site. Data were analyzed by Epi Info software program

    Results: Out of 161 negative samples by direct smear and culture, seven samples (4.3%) were posi­tive by PCR technique.

    Conclusion: Diagnosis of trichomoniasis by PCR is a sensitive and specific method that could play important role to help the physicians for properly treatment and control of infection.

  • XML | PDF | downloads: 142 | views: 245 | pages: 37-41

    Background: The aim was to study the gastro-intestinal helminths of stray dogs of Garmsar, Sem­nan Province, Central Iran, and its impacts on human health and animal production.

    Methods: During 2006, the alimentary tracts of 50 stray dogs at necropsy, selected from villages around Garmsar, were removed, and examined for helminth infections. Subsequently helminths were collected from the contents of each part and scraped sample of small intestines of washed materials in a 100-mesh sieve. To identify the species of helminths, the nematodes were cleared in lactophenol and cestodes were stained using carmine acid.

    Results: Mixed infection was the rule and 40 dogs (80%) harbored more than one species of helminth. Taenia hydatigena was the most prevalent species (80%) followed by Echinococcus granulosus (64%), Toxocara canis (22%), Mesocestoides lineatus (12%), Taenia multiceps (10%) and Dipylidium caninum (4%). The mean intensity of worm infection was low (1-3) ex­cept for that of E. granulosus (645). No significant difference was noticed between sex, age and most helminth infections except for that of sex and T. hydatigena  (P=0.001) as well as age and T. canis (P=0.001).

    Conclusion:  Although human infection with T. hydatigena is unlikely, but other helminths re­ported in this study are of zoonotic importance, and may pose a threat to community health, and reduce the productions of ruminants harboring taeniid metacestodes.

  • XML | PDF | downloads: 168 | views: 184 | pages: 42-47

    Background: Cryptosporidium is a protozoan parasite with worldwide distribution. The aim of this study was to estimate the prevalence of Cryptosporidium infection by antigen detection in faeces among immunocompromised patients referred to educational hospitals of Ahvaz City, South-West of Iran, 2009-2010.

    Methods: Fecal samples from 176 immunocompromised patients were collected and Cryptosporid­ium coproantigen test was performed using ELISA method (DRG kit, Germany). A questionnaire was completed for each case and the results were analyzed using descriptive and Chi-Square tests, by SPSS statistical software (15th version).

    Results: Our study indicated 5.1% Cryptosporidium infection prevalence in the immunocompro­mised participated population. Furthermore, 4.2 %, 4%, 4.5 % and 9.1% infection rates were identi­fied in children suffered from hematopoietic malignancy, adult cancer patients, renal trans­plant recipients, and HIV+ cases, respectively. There was not significant correlation between the infection and age and gender (P>0.05).  Infection was most frequent among HIV+ patients.

    Conclusion: The present study confirmed the high prevalence of Cryptosporidium antigen in fe­cal samples of immunocompromised patients in the region. As no chemotherapeutic agents have yet proven, especially in immunosuppressed patients, therefore our results highlight the impor­tance of preventive intervention in these groups.

  • XML | PDF | downloads: 238 | views: 292 | pages: 48-54

    Background: Coccidiosis is an intestinal disease of chickens caused by various species of proto­zoan parasites within the genus Eimeria. Diagnosis and genetic characterization of different spe­cies of Eimeria are central to the prevention, surveillance, and control of coccidiosis. The aim of this study was to detect different chicken Eimeria species from several areas in Khuzestan, south­west Iran.

    Methods: From February to September 2008, PCR assay as well as parasitological examinations was applied for the identification of field isolates of Eimeria parasites around Ahvaz, center of Khuzestan, southwest Iran. Data were analyzed by the Kappa statistic test.

    Results: Eimeria maxima, E. necatrix, E. tenella, E. acervulina and E. mitis were detected in this study. The prevalence of Eimeria spp. was 31.5% (126 of 400) and E. tenella was the most preva­lent species in Khuzestan. Based on the Kappa statistical test, a good correlation between the results of PCR and traditional biometrical methods was only observed for E. maxima.

    Conclusion: The present study is the first on the prevalence of Eimeria species in Khuzestan, based on the molecular findings. We believe that traditional methods are not sufficiently reliable for specific diagnosis of Eimeria species in chickens and PCR based amplification of DNA se­quence of parasite, could resolve this problem.

  • XML | PDF | downloads: 157 | views: 194 | pages: 55-62

    Background: The IFA test is one of the most usual methods for detecting anti-Toxoplasma antibod­ies, although it has not any unique standardization. It seems that the microscopic judg­ment of results is an important confounder in IFA test. Therefore, we conducted the present study to clarify the role of microscopic observer, and other confounders on the test.

    Methods: Eighty sera were collected from patients suspicious to toxoplasmosis for detection IgG anti-T. gondii by this test. Samples were examined against different series of antigens, IgG anti-human conjugates, and observers.

    Results: There were no significant differences between the two series of antigens and conjugates. For the observers groups the kappa coefficient of the test results in the experts group (0.97, 0.94-1.00) were significantly higher than the less experienced observers (0.77, 0.68-0.87).

    onclusion: We recommend the IFA test to be performed only in reference laboratories and by laboratory technicians that have enough experience for this test. Otherwise, we suggest the substitution of this test with other tests like ELISA for the diagnosis and epidemiological studies.