Search

Mucosal leishmaniasis is a well-known clinical manifestation of infections mainly caused by New World Leishmania species, especially Leishmania braziliensis (Viannia) in Central and South America. It is extremely uncommon in the world, even in the endemic areas such as Fars Province, Southern Iran. Two male immunocompetent subjects who developed Leishmania mucosal lesion mimicking a laryngeal tumor presented with a several-months history of dysphonia, dyspnea, hoarseness, and odynophagia. Multiple smears from the lesions showed structures resembling the amastigote form of Leishmania. Nested PCR analysis to amplifying a fragment of Leishmania infantum kinetoplastid DNA from the Giemsa-stained smear resulted in a fragment of 680 bp. Sequence analysis of one of the strains showed 98 % similarity to L. infantum strain IranJWinf (GenBank accession no. AB678348.1) and 96 % similarity to L. infantum isolate MCAN/ES/98/10445 (GenBank accession no. EU437407.1), while another strain showed 97 % similarity with two L. infantum strains from kala-azar patient (GenBank accession nos. AJ223725.1 and AF027577.1). Immunocytochemical staining with anti-L. infantum mAb (D2) was positive. Primary mucosal leishmaniasis (ML) may occur in the immunocompetent patients who reside in or travel to endemic areas of leishmaniasis. Mucosal leishmaniasis contracted in endemic areas, such as Iran, has to be considered in the differential diagnosis of lesions in the other mucosa and may occur in previously healthy persons. Therefore, cytology, PCR, and immunocytochemistry-based methods with anti-Leishmania mAb are helpful in the diagnosis of ML.

Theileriosis is an economically important hemoprotozoal disease with high morbidity and mortality in cattle. The present study reported the pathological features of a natural outbreak of tropical bovine theileriosis due to Theileria annulata in Fars Province, southern Iran. T. annulata was confirmed by the presence of T. annulata piroplasms in the blood smears and also by polymerase chain reaction test. On necropsy, pale mucous membranes and petechial and ecchymotic hemorrhages in the mucosal and serosal surfaces together with lymphadenopathy were observed. The liver was friable, yellowish, and larger than normal. Hemorrhages and punched-out ulcers were observed in the abomasal mucous membrane. Severe petechial hemorrhages were seen in the skin particularly in the hairless areas. Pulmonary edema and emphysema with petechial and ecchymotic hemorrhagic foci in the lungs were evident. The main histological changes were proliferation of lymphocytes in the lymph nodes and proliferation of macrophages, lymphocytes, and plasma cells in the spleen, Peyer's patches, portal tracts of the liver, and interstitial tissue of the kidneys. The mucous membrane of the abomasum showed numerous multifocal areas of necrosis and ulceration, and the submucosal area and lamina propria adjacent to these lesions showed hyperemia and hemorrhages, with mononuclear cell infiltration. The skin showed multifocal necrotic changes, petechial and ecchymotic hemorrhages, and chronic dermatitis. The schizonts of Theileria were evident in the cytoplasm of the lymphocytes and macrophages of the lymph nodes, spleen, and skin. Molecular examination revealed that these animals were infected with T. annulata. The present study describes the clinicopathological findings of bovine tropical theileriosis in an unpredictable weather condition.

This study was conducted to identify genetic characteristics of Besnoitia spp. isolated from goat in Iran. Molecular analysis of two portions of nuclear ribosomal DNA (ITS1 and ITS2) was used for the genetic characterization of the Besnoitia species. Comparison of the sequencing data of the Iranian Besnoitia samples obtained in the present study (GenBank accession number HM008988) with those previously reported for other Besnoitia spp. in the GenBank database revealed a particularly close relationship between the present goat Besnoitia samples and the Besnoitia samples from the cattle, caribou, and equids (Besnoitia besnoiti, Besnoitia tarandi, and Besnoitia bennetti). This is the first use of a genetic approach to interrogate the identity of the species of Besnoitia infecting Iranian goats. Also, the results of the present study showed the occurrence of a similar sequence polymorphism for ITS1 and ITS2 in all Iranian isolates, which exhibit 100% identity in these ribosomal sequences, to those of B. besnoiti previously reported from Israel. Although the ITS1 sequence of Iranian goat isolates is identical to European cow isolates, the ITS2 sequences derived from present Besnoitia genotype differed in one nucleotide position compared with other European B. besnoiti. Further studies should be employed based on this molecular data to identify the natural definitive host in order to complete the life cycle of this distinct genotype of parasite.

A total of 1,070 camels of different ages and of both sexes slaughtered at Mashhad slaughterhouse were inspected for infection with Dipetalonema evansi. Microfilariae were found in peripheral blood smears of 221 (20.7%) camels (14% females and 23% males). In a second study, the testicles, epididymises, spermatic cords, and lungs of 197 male camels were examined, and 165 (83.7%) were infected with adult forms of D. evansi. Tissue sections from 30 infected and ten uninfected camels were collected and processed routinely for further histopathological studies. The arteries infected with D. evansi in the region of nodules in testis showed chronic reaction characterized by proliferative and hyperplastic changes of the endothelial and fibrous connective tissue layers, narrowing the lumen or occluding it. The testicles were either hypertrophic or atrophic and showed chronic orchitis with infiltration of lymphocytes, eosinophils, macrophages and fibroblasts, parenchymal degeneration, and necrosis and, in some cases, with hematoma and hydrocele formation. Necrosis of the alveolar walls, atelectasis, pulmonary edema, and fibrosis of the pulmonary parenchyma with chronic interstitial pneumonia and rarely mineralization of the wall of the blood vessels were also seen in some of the infected animals. D. evansi is highly endemic and constitutes an important health problem to camels in this area, resulting in high morbidity, impaired working capacity, and lowered productivity.

This study was made to determine the distribution pattern of Toxocara cati larvae in chickens as a paratenic host and its potential zoonotic risk by consuming infected chickens. Two groups of chickens were fed with 1,000 and 3,000 embryonated eggs of T. cati. The chickens were necropsied 3, 7, 14, and 21 days postinfection. The liver, lungs, kidneys, spleen, small intestine, and half of all the striated muscles were digested for larval recovery. Squash method was used for brain. Larvae were recovered from the liver and brain of infected chickens with 1,000 embryonated eggs. Samples of these tissues were prepared for histopathologic studies. Experimental chickens exhibited hemorrhages in the liver, lungs, and kidneys on all days postinfections (dpi). White spots on the liver surfaces that showed necrotic foci, infiltration of eosinophils, and a few lymphocytes around necrotic areas were seen on 14 and 21 dpi. Remains of larvae were present in the liver on 14 dpi. Pathologic findings showed that larvae migrated in different organs of chickens. We suggest that chickens could be paratenic hosts, and human infection with T. cati might occur after consumption of raw or undercooked meat of infected chicken with T. cati.

Sheep and goats serve as intermediate hosts for the canine tapeworm Taenia multiceps. The cysts produced by the intermediate stage of parasite are usually found in the cerebral hemispheres of small ruminants, and the resulting disease is commonly known as coenurosis. Coenurosis is clinically manifested in the form of various nervous symptoms, depending on the exact location of the cyst. The variety of neurological symptoms contributes to the complexity of clinical diagnosis and reinforces the need for a more specific and acceptable diagnostic approach. We demonstrated here, for the first time, that the T. multiceps DNA is present in the cerebrospinal fluid (CSF) of the infected sheep and goats. In addition, the molecular genetic marker of the mitochondrial DNA was applied phylogenetically to show that our isolates together with other T. multiceps strains comprised a monophyletic group that is a sister to Taenia krabbei. Pairwise comparison between the cox1 sequences of our study and other T. multiceps genotypes existing in the GenBank showed similarity ranging from 98 to 100%. Accordingly, the polymerase chain reaction (PCR) can be used for amplification of DNA of the parasite originated from the CSF and provides a valuable method for accurate identification of coenurosis cases.

Leishmania tropica is one of the main etiological agents of cutaneous leishmaniasis in Iran. For ultrastructural and isoenzyme study, axenic amastigotes were cultured in a brain-heart infusion medium containing 20 % fetal calf serum, pH 4.5, and incubated at 37 °C in 5 % CO(2). Different stages of L. tropica revealed the same isoenzyme profiles after comparing four enzyme systems including phosphoglucomutase, 6-phosphogluconate dehydrogenase, malate dehydrogenase, and nucleoside hydrolase II. Different isoenzyme patterns for glucose-phosphate isomerase, glucose-6-phosphate dehydrogenase, nucleoside hydrolase I, and malic enzyme enzymic systems were seen; thus, these isoenzyme systems among the eight systems studied were more efficient in characterizing L. tropica amastigotes. The structure of the axenic amastigotes was essentially similar to that of the promastigotes except for some important characteristics including the flagellum, flagellar pocket, paraxial rod, and the subpellicular microtubules.

Four Sarcocystis species, i.e., Sarcocystis fusiformis and Sarcocystis buffalonis with cats as definitive hosts, Sarcocystis levinei with dogs as definitive host, and Sarcocystis dubeyi with unknown definitive host, have previously been described from water buffalo (Bubalus bubalis). The aim of the present study was genetic characterization of the causative agent(s) of water buffalo sarcocystosis in Khuzestan Province, western Iran. RFLP-PCR and partial sequence analysis of 18S rDNA gene were used for the genetic characterization of the specimens directly obtained from water buffalo. In RFLP-PCR, four restriction enzymes (Dra1, Ssp1, Fok1 and Bsl1) were used for species discrimination of Sarcocystis spp. in this host. Comparison of the molecular sequencing results and RFLP-PCR pattern of the samples obtained in the present study with those previously reported for different Sarcocystis spp. revealed that all positive Sarcocystis samples represented S. fusiformis. To our knowledge, this is the first demonstration of the existence of S. fusiformis in the Iranian water buffalo population by a genetic approach. In addition, comparison between the alignments between the Iranian 18S rDNA sequences (HQ703791), made in this study, and those previously reported for S. fusiformis in different geographical location (accession nos. AF176927, AF176926, and U03071) showed the occurrence of local genetic polymorphisms and heterogeneity in this ribosomal locus. Despite the occurrence of some genetic variations in the hypervariable regions of the 18S rDNA in S. fusiformis, Dra I restriction site was conserved among all sequences available. According to the present study, it seems that cats have a more significant epidemiological role than dogs in transmission of sarcocystosis agent to water buffalo in Iran.

A disease with clinical manifestations of thickening and alopecia of the skin over the lower limbs, around the eyes, face, and nose, thickening and shrinkage of the scrotum, and presence of white granular cysts in the sclero-conjunctiva in goats in Kerman Province, were reported to the Pathology Department of Shiraz Veterinary School. Primary histopathological studies demonstrated an outbreak of caprine besnoitiosis in this region. To study the histopathological and ultrastructural features of the disease, samples were collected from various organs of the suspected slaughtered goats for further investigations. In histopathological studies, dermis and subcutaneous fascia covering lower portion of the limbs, skin over frontal sinus, ear tips, scrotum, eye lids as well as the eye's sclera, epididymal and testicular parenchyma, and their tunics were severely infected with Besnoitia cysts. Tongue, pharynx, prepuce and penis, deeper striated muscles, subcutaneous bone matrices, abomasum, esophagus, subcutaneous tendons, and periosteal surfaces of the limb bones showed lower rates of infection. Except the vagina and vestibule, no cyst was observed in other female urogenital organs, the central nervous system, intestines, heart, liver, spleen, and different lymph nodes. The host reaction to the cysts was variable, ranging from the absence of inflammatory cells around intact normal cysts up to infiltration of macrophages, lymphocytes, plasma cells, eosinophils, fibroblasts, and connective tissues around the degenerated cysts. Ultrastructural studies showed this coccidian parasite belonged to eukaryotic protozoa, and the cystic form had the typical feature of the Besnoitia spp. of the apicomplexa. This study showed that the organism demonstrated ultrastructurally minor differences with other Besnoitia species infecting other animal species.