Characterization of Leishmania isolated from unhealed lesions caused by leishmanization

Leishmania parasites were isolated after 13 and 8 years from the unhealed lesions of 2 soldiers who had been immunized against leishmaniasis during the war between Iraq and the Islamic Republic of Iran. Isoenzyme characterization on these isolates using 11 enzyme systems was carried out and the results were compared with the enzyme profiles of the original isolates of L. major used for leishmanization. Minor enzymatic differences in glucose-6-phosphate dehyrognase and phosphoglucomutase were observed but otherwise the strains appeared unchanged

Characterization of leishmania parasites from archived geimsa-stained slides using nested polymerase chain reaction

In Iran, the clinical presentation of cutaneous leishmaniasis is mainly in the form of dry type [urban form] or wet type [rural form]. The microscopic finding of amastigotes in Giemsa-stained smears is the most practical laboratory test for the diagnosis of cutaneous leishmaniasis. However, determination of parasite species is not possible when using this method. Parasite characterization is made by various biochemical, immunological and molecular methods based on massive culture of the parasites. In this study nested PCR was used both for diagnosis as well as species identification. Giemsa-stained slides from forty-nine patients, that had been included in a drug resistance survey, were used in this study. From the available slides, forty-seven were diagnosed as having leishmaniasis using the nested PCR technique. Twenty of these were Leishmania tropica [L. tropica] and the remaining were Leishmania major [L. major]. Amastigotes were recovered from twenty-nine of these patients after standard treatment. This study revealed that clinically drug-resistant cases are more likely to be infected with L. tropica than with L. major, although this difference was not statistically significant. L. tropica was mostly present in facial lesions while L. major was mostly detected in hand and foot lesions. In patients with more than two lesions, L major was the predominant cause. L tropica was the cause of a more prolonged duration of disease. None of the above findings were, however, statistically significant. It can be concluded that nested PCR is a useful technique for studying the molecular epidemiology of leishmaniasis in the field

Characterization of Leishmania parasites isolated from provinces of the Islamic Republic of Iran

Leishmania parasites isolated in the Islamic Republic of Iran were studied by a random amplified polymorphic DNA polymerase chain reaction [RAPD-PCR]. Of 82 isolates, 80 were from cutaneous lesions, 1 from a human throat lesion and 1 from a dog. Of these, 42 isolates were L. tropica, 36 were L. major and 2 were L. infantum. There were 2 unidentified isolates [from the throat lesion and a cutaneous lesion] and these demonstrated 52% and 48% similarity with L. tropica and L. infantum. Both L. tropica and L. major were isolated from four provinces indicating a recent change in the epidemiology of cutaneous leishmaniasis. L. tropica was isolated from three provinces; L. major from one province. L. infantum was isolated from a human cutaneous lesion and from a dog in Bushehr province

Diagnosis of cystic echinococcosis: ultrasound imaging or countercurrent immunoelectrophoresis?

Cystic echinococcosis is a major zoonotic diseases in the Islamic Republic of Iran. This study was carried out in 3 general hospitals in Shiraz. We examined the records of all 1227 surgical patients with a surgically-proven diagnosis of cystic echinococcosis for the 20-year period 1978-98. The results of countercurrent immunoelectrophoresis were compared with pathology and ultrasound reports to determine whether serological tests could be helpful for diagnosis. Countercurrent immunoelectrophoresis could detect only 62.0% of cases, whereas the pathology and ultrasound results were positive for 96.3% of cases. This study confirms the usefulness of ultrasound and suggests that only in doubtful cases would countercurrent immunoelectrophoresis be useful for diagnosing cystic echinococcosis

Isoenzyme studies in characterization of leishmania isolated in Iran

Phenotypic characters of the Leishmania organisms are very similar. Isoenzyme electrophoresis has provided an effective and reliable tool for characterization of Leishmania. To determine the isoenzyme profiles of Leishmania organisms isolated in Iran. Leishmania organisms were recovered from patients suspected of cutaneous leishmaniasis [CL] from various parts of Iran and in a few cases from Afghanistan. Isoenzyme profiles of these isolates were compared with those of reference strains of L. tropica, L. major and L. infantum using polyacrylamide gel electrophoresis and 11 enzyme systems. Seventy two isolates of Leishmania were recovered from 407 patients suspected of CL. The isoenzyme pattern of 42 and 23 isolates were compatible with L. major, and L. tropica, respectively, according to the WHO reference strains. There were also 9 and 14 different strains, respectively within the L. major and L. tropica isolates. For the first time in Iran L. infantum was identified as the causative agent of CL. It was found that isoenzyme systems used in this study are able to detect different strains within the Leishmania species. It was determined that L. tropica was the causative agent in most cases of lupoid form of CL

Leishmanin skin test in hyperendemic foci of zoonotic cutaneous leishmaniasis in Farris province, Iran

During the 1990-1992 interval, epidemics of zoonotic cutaneous leishmaniasis were observed in Neiriz and Estahban, two villages in the eastern region of Fars Province. Over one third of the population was infected. From August to September 1993, over 2180 individuals in these villages were studied by systematic random sampling. Members of each household were assessed for the presence or absence of Leishmania scars, and then were tested with leishmanin. Scars of cutaneous leishmaniasis [CL] were observed in 746 of the 2180 individuals tested [34.2%]. Among the group with cutaneous leishmaniasis scars 87% had positive leishmanin skin test, in contrast to 33% of individuals in the same household without scars

Studies on the causative agent of cutaneous leishmaniasis in Shiraz Iran

Leishmania species were isolated from 14 patients with acute cutaneous leishmaniasis [CL] in Shiraz. The isolated organisms were injected subcutaneously into the base tail of 14 groups of Swiss outbred white mice. Each group consisted of 10 mice and each mouse received 2xl0 promastigotes. During 4-6 weeks after inoculation, smears and cultures were taken from this site and the isolated organisms were inoculated into a new series of mice. During 6-8 weeks after inoculation, erythema was observed in only two groups of these animals. No ulceration or open lesion, which are characteristics of L. major, were noticed in the inoculated mice. Upon direct smear preparation from these two groups of animals only a few organisms were seen with no growth in cultures. On the basis of these observations we concluded that the Leishmania isolated from the patients with acute CL in Shiraz is Leishmania tropica. Various factors which contribute to the survival of the organisms at the site of inoculation without formation of open lesions are discussed

Studies on the T-cell phenotypes in children with Kala-azar in Fars province, Iran

The subpopulations of T-lymphocytes were studied in children with visceral leishmaniasis in the active stage of disease prior to treatment [n=28] and in controls [n=15] using specific monoclonal antibodies [Behring OKT3, OKT4 and OKT8]. The percentage of total peripheral blood T-lymphocytes [CD3 [+]T-cells] in patients were within the same range as those of normal children [71 -09 +/- 1.07 vs 68.89 +/- 1.29]. The percentage of CD4[+] T-lymphocytes showed a significant increase [P<0.005] in comparison with the control [53.92 +/- 1.20 vs 45.59 +/- 1.35]. A decrease in the percentage of CD8" T-lymphocytes [20.81 +/- 0.71 vs 23.89 +/- 0.72] was observed which was significant at [P<0.025]. The ratio of CD4+/CD8+T- lymphocytes was significantly increased atP<0.005 as the value of the ratio was 2.70 +/- 0.17 for kala-azar patients and 1.91 +/- 0.05 for the controls. The immunosuppression in kala-azar patients studied could be due to dysfunction of antigen specific T-cells and its subsequent effect on various cytokine release rather than changes in the phenotypic characters of these cells