Canine Heartworm in Southeastern of Iran with Review of disease distribution

Background

Heartworm (Dirofilaria immitis) is mosquito-borne filarial nematode capable of causing serious cardiopulmonary disease in canines and felines, and pulmonary dirofilariasis in man. This research was conducted with the objectives of determining the incidence and assessing possible risk factors of canine heartworm in the southeast of Iran.

Methods

From October 2012 to September 2013, blood samples from 87 dogs from Zabol area in Sistan and Baluchestan and 33 dogs from Bam area in Kerman Province were examined for detection of Dirofilaria immitis using modified knott test and serology.

Results

Out of 120 dogs, 29 (24.2%; 95%CI: 16.6-31.8%) were positive, serologically. The overall seroprevalence of D. immitis in dog in Zabol and Bam was 27.5% (95% CI: 24.7-32.5%) and 15.15% (95% CI: 12.3-20.7%), respectively. 28.8% of stray dogs and 20.6% of housed dogs in the study areas were seropositive. Seroprevalence of D. immitis was not significantly different between stray and housed dogs (P = 0.295). Investigation of seasonal dynamic of infection with D. immitis in stray and housed dog showed that the proportion of infected dog in spring and summer was greater than colder season (autumn and winter) which was not significant. The prevalence of infection with D. immitis in >5 years old stray dogs (53.8%) was greater than other age categories while in housed dogs infection rate was greater in 3-5 years old (27.3%).

Conclusion

It is important to point out the increased incidence of canine heatrworm in Iran. In order to stop the spread of canine heartworm, preventive measures must be taken now.     

The Effects of Babesiosis on Oxidative Stress and DNA Damage in Anatolian Black Goats Naturally Infected with Babesia ovis

Background

A reactive oxygen and nitrogen intermediate produced during an inflammatory response is the important part of host-defense strategies of organisms to kill the parasite. However, it is not well known whether these intermediates cause DNA damage and oxidative stress in goats infected with Babesia ovis. The purpose of this study was to clarify the effects of babesiosis on basal levels of DNA damage and oxidative status of goats naturally infected with B.ovis.

Methods

DNA damage and antioxidant parameters were determined in B. ovis infected goats. Ten infected Anatolian Black Goats with B. ovis diagnosed via clinical signs and microscopic findings and ten healthy were used in the study.

Results

The Babesia infection increased the levels of DNA damage, malondialdehyde (MDA), protein carbonyl content (PCO) and plasma concentration of nitric oxide metabolites (NOx), and decreased total antioxidant activities (AOA) and reduced glutathione (GSH). A significant positive correlation between DNA damage, MDA, PCO, and NOx concentrations was found in the infected goats. DNA damage showed a negative association with AOA and GSH concentrations in the infected goats.

Conclusion

The Babesia infection increases oxidative stress markers and DNA damage and decreases AOA in goats. These results suggest that the increases in the production of free radicals due to Babesia infection not only contribute to host-defense strategies of organisms to kill the parasite but also induce oxidative damage in other cells.     

Genetic Identification of Trichomonas vaginalis by Using the Actin Gene and Molecular Based Methods

Background

Trichomonas vaginalis is the agent of urogenital tract infection that causes human trichomoniasis with some serious health complications. More understanding about genetic features of the parasite can be helpful in the study of the pathogenesis, drug susceptibility and epidemiology of the infection. For this end, we conducted analysis of the actin gene of T. vaginalis by applying the PCR-SSCP (PCR-Single Stranded Conformational Polymorphism) and nucleotide sequencing method.

Methods

Fifty T. vaginalis samples were collected from 950 women attending gynecology clinics in two cities of Iran, Hamadan and Tehran, from November 2010 to July 2011. After axenisation of isolates, all samples subjected to PCR-SSCP and nucleotide sequencing.

Results

According to the SSCP banding patterns and nucleotide sequencing, seven sequence types were detected among the isolates. Alignment of the nucleotide sequences showed five polymorphic sites in the different strain types. Amino acid substitution was not observed in the nucleotide sequence translation of the all sequences.

Conclusion

The actin gene analysis represents genetic diversity of T. vaginalis and it suggests that various strains can be responsible for clinically different trichomoniasis in infected individuals. It is expected that further studies will be conducted to increase our knowledge about relationship between the actin gene polymorphism and different biological behavior of the parasite.     

An Analysis of Clinical Characteristics of Strongyloides stercoralis in 70 indigenous patients in Iran

Background

Clinical manifestations of Strongyloides stercoralis are variable from asymptomatic to hyperinfection and devastating disseminated infections. Hereby, clinical characteristics of a large series of Iranian strongyloidiasis indigenous cases are described.

Methods

The records of people referred to the Helminthological Diagnostic Laboratory of School of Public Health, Tehran University of Medical Sciences and School of Medicine, Gilan University of Medical Sciences, during 2009-2013 were reviewed. For those patients that were infected with S. stercoralis and their clinical manifestations and demographic data were available (70 cases) a checklist was prepared and data analyzed.

Results

Forty-three patients (61.4%) were male and 27 (38.6%) female. Gastrointestinal, cutaneous and pulmonary symptoms were present in 71.4%, 25.7%, and 15.7% of patients, respectively. None of them had larva currens eruption. Eosinophilia was the most prevalent reason for suspicious on S. stercoralis, but the mean was lower in elderly patients. Hyperinfection were recorded in 8 patients (11.4%), and 2 cases had disseminated infection.

Conclusion

Eosinophilia is common both in asymptomatic and symptomatic cases of strongyloidiasis, but the mean tend to lower with increase in age.     

PCR-RFLP Analysis of 28 SrDNA for Specification of Fasciola gigantica (Cobbold, 1855) in the Infected Lymnaea auricularia (Linnaeus, 1785) Snails from Northwestern Iran

Background

Fasciolosis in livestock is a crucial concern in the globe, mainly due to its impact on human health. The aim of this study was to determine the rate of infection with Fasciola gigantica (Cobbold, 1855) larvae in the field-collected snails of Lymnaea auricularia (Linnaeus, 1785) from northwestern Iran using a molecular approach.

Methods

A total of 6,759 pond snails were collected from 28 freshwater bodies in West Azarbaijan. PCR was performed to amplify a 618-bp fragment of the nuclear 28 SrRNA gene of Fasciola. The PCR products were digested by AvaII restriction enzyme to create restriction fragment length polymorphism (RFLP) patterns specific for the detection of F. gigantica.

Results

Of the total collected snails 496 (7.34 %) were L. auricularia, among which 4.64% (23 out of 496) were infected with a Fasciola species according to the PCR analysis. Only 2.22% (11 out of 496) of the infected snails were from the mountainous areas. The highest Fasciola infection rate recorded in the snails of a single site was 1.81% (9 out of 496 snails). Based on the RFLP pattern, F. gigantica accounted for 2.42% of the infection rates in the study sites.

Conclusion

Application of PCR-RFLP was proven to be a useful approach for valid and robust detection of the infection with F. gigantica in its intermediate host snails. These findings may therefore be applicable for establishment of the control programs against dissemination of the infection in different regions.     

A Preliminary Parasitological Survey of Hepatozoon Spp. Infection in Dogs in Mashhad,Iran

Background

We attempted to determine the prevalence of Hepatozoon spp. infection in Mashhad, northeast of Iran, via blood smear parasitology.

Methods

The prevalence was investigated by examination of blood smear parasitology, using blood samples collected from 254 dogs (51 strays and 203 privately owned-dogs).

Results

Two stray dogs (2/51; 3.92%) and two privately-owned dogs (2/203; 0.98%) were infected with Hepatozoon spp. Therefore, as per blood smear parasitology, the prevalence of Hepatozoon spp. infection was 1.57% (4/254). Sixteen out of 254 dogs (6.29%) were infested with ticks; all of which were Rhipicephalus sanguineus. One of the dogs infected with Hepatozoon spp. exhibited ticks at the time of examination. Concurrent infection with Ehrlichia canis and Leishmania infantum was not detected in the four Hepatozoon spp. infected dogs.

Conclusion

This is the first epidemiological study on the prevalence of Hepatozoon spp. infection in dogs in Iran.     

Isolation,Identification, and Pathogenicity of Neospora caninum China Yanbian strain

Background

The aim of the study was to provide a point of reference to study the Neospora caninum infections in China.

Methods

Genome DNA was extracted from the brains of aborted fetuses and specific PCR was performed with N. caninum Nc5-targeted specific primers. Fetal bovine brain tissues were homogenized and continuously cultured in Vero cells with double antibodies. The medium was replaced at 2-d intervals and the state of cells was observed.

Results

A 608 bp Nc5 gene band was detected by PCR amplification. After sequencing, the sequence of the sample shared 99.5% homology with GenBank ({"type":"entrez-nucleotide","attrs":{"text":"AF061249","term_id":"4154231","term_text":"AF061249"}}AF061249). Brain homogenates were continuously cultured in Vero cells for 34 d and N. caninum was found. The results of IFAT and Nc5 gene-based PCR detection were N. caninum-positive, and the parasite was tentatively named N. caninum China Yanbian strain. BABL/c mice were inoculated with the separated parasites and showed clinical symptoms of ataxia and limb paralysis after 12 d. Only 3 mice survived. The blood of dying mice and the hearts, livers, spleens, lungs, kidneys, and brains of dead mice were collected aseptically. The Nc5 gene-based PCR showed that N. caninum may exist in brains, livers, and spleen. Based on immunohistochemical observations, we showed that N. caninum tachyzoites existed in the brains and livers.

Conclusion

We have successfully isolated bovine-specific N. caninum strain from brain tissues of aborted cattle in the China Yanbian region. This isolated strain has a strong infectious ability towards BABL/c mice.     

Molecular and Parasitological Study of Cryptosporidium Isolates From Cattle in Ilam,West of Iran

Background

Cryptosporidiosis is one of the most important parasitic infections in human and animals. This study was designed for survey on the prevalence of Cryptosporidium infection in farms of Ilam, west of Iran, using parasitology method and genotyping by Nested PCR-RFLP.

Methods

Fecal samples of 217 cattle were collected fresh and directly from the rectum of cattle. All of the samples were examined by microscopic observation after staining with modified Ziehl-Neelsen (MZN). Genomic DNA extracted by using EURx DNA kit. A Nested PCR-RFLP protocol amplifying 825 bp fragment of 18s rRNA gene conducted to differentiate species and genotyping of the isolates using SspI and VspI as restriction enzymes.

Results

The prevalence of Cryptosporidium infection in cattle using both methods is 3.68%. Most of the positive cattle were calves under six months. Species diagnosis carried out by digesting the secondary PCR product with SspI that C. parvum generated 3 visible bands of 448, 247 and 106 bp and digested by VspI restriction enzyme generated 2 visible bands of 628 and 104bp. In this investigation all of the positive samples were Cryptosporidium parvum.

Conclusion

C. parvum (bovine genotype) detected in all positive cattle samples in Ilam, west of Iran. The results of the present study can help for public health care systems to prevention and management of cryptosporidiosis in cattle and the assessment of cattle cryptosporidiosis as a reservoir for the human infection.     

Immunotherapy Using Autoclaved L. major Antigens and M. vaccae with Meglumine Antimoniate,for the Treatment of Experimental Canine Visceral Leishmaniasis

Background

To evaluate immunotherapy against canine visceral leishmaniasis, Leishmania major antigen and heat-killed Mycobacterium vaccae (SRL172) were used as stimulators of immune defense mechanisms and the results were compared with standard chemotherapy meglumine antimoniate.

Methods

Nineteen mongrel dogs aging 1-3 years old were used in this experiment. Infection was carried out in 15 out of 19 dogs using L. infantum, isolated from a naturally infected poly-symptomatic dog.

Results

All the cases showed positive serologic results by direct agglutination test during 30-60 days following inoculation. In the first group, which was under chemotherapy (Glucantime^R), one of the members showed recurrence of the disease despite rapid effect of the therapeutic protocol. Immunotherapy using SRL172 caused complete cleaning of the parasite in group 2, but the speed was less than Glucantime. Immunotherapy using L. major antigen combined with M. vaccae in group 3 and combine administration of immunotherapy and chemotherapy in group 4 both were with relapsing of one case in each group. Group 5 and 6 were consisted of positive and negative control dogs, respectively.

Conclusion

Immunotherapy seems to be an adjuvant in treatment of canine leishmaniasis but it needs more investigation for final confirmation.     

Prevalence of Balantidium coli Infection in Bred Rhesus Monkeys (Macaca mulatta) in Guangxi,southern China

Background

Balantidium coli infects humans, primates and pigs, causing serious diarrhea and dysentery. Little information on the prevalence of B. coli in primates is available in China. This investigation was conducted to determine the prevalence of B. coli infection in bred rhesus monkeys in Guangxi Zhuang Nationality Autonomous Region (GZNAR), southern China.

Methods

A total of 120 fecal samples were collected from rhesus monkeys bred in cages in GZNAR and B. coli cysts and/or trophozoites were examined microscopically after sedimentation with water in May 2013.

Results

(64.2%) samples were tested positive. The prevalence was 65% (39/60) and 63.3% (38/60) in female and male monkeys, respectively. 80% (48/60) cages in this nonhuman primate center were positive for B. coli.

Conclusion

The present survey revealed high circulation of B. coli in bred rhesus monkeys in GZNAR, which poses potential threats to animal and human health.     

Emerging Intestinal Microsporidia Infection in HIV+/AIDS Patients in Iran: Microscopic and Molecular Detection

Background

Species of Microsporidia have been known as opportunistic obligate intracellular parasites particularly in immunocompromised patients. Enterocytozoon bieneusi is one of most prevalent intestinal microsporida parasites in HIV⁺/AIDS patients. In this study, intestinal microsporidia infection was determined in HIV⁺/AIDS patients using microscopic and molecular methods.

Methods

Stool samples were collected from HIV⁺/AIDS patients during 12 months. All of the stool specimens washed with PBS (pH: 7.5). Slim slides were prepared from each sample and were examined using light microscope with 1000X magnification. DNA extraction carried out in microscopic positive samples. DNA amplification and genus/species identification also performed by Nested-PCR and sequencing techniques.

Results

From 81 stool samples, 25 were infected with microsporidia species and E. bieneusi were identified in all of positive samples. No Encephalitozoon spp. was identified in 81 collected samples using specific primers.

Conclusion

E. bieneusi is the most prevalent intestinal microsporidia in immunocompromised patients of Iran. On the other hand, Nested-PCR using specific primers for ssu rRNA gene is an appropriate molecular method for identification of E. bieneusi.     

Molecular Detection and Identification of Theileria Species by PCR-RFLP Method in Sheep from Ahvaz,Southern Iran

Background

The present study was carried out to investigate the accurate status of ovine Theileria infection in sheep from Ahvaz and surrounding region, a tropical area southwest Iran.

Methods

A PCR-RFLP method based on 18S ribosomal RNA gene was designed which could detect and differentiate Theileria and Babesia spp. and also differentiate main Theileria species in sheep at the same time. 119 sheep blood samples were collected from Ahvaz and surroundings.

Results

Microscopic examination of blood smears revealed 69.7% (83/119) infection with Theileria spp. Of the total samples subjected to PCR, 89% (106/119) were found to be positive, all of which were identified as Theileria by RFLP analysis using enzyme Hind II. In enzymatic digestion of PCR products by Vsp I, 91.5% (97/106) of Theileria positive samples were identified as T. ovis while mixed Theileria infections were found in 9 samples. The samples with mixed infections were analyzed with an additional nested PCR-RFLP method, by HpaII enzyme digestion. 3 samples with T. lestoquardi infection, 1 sample with T. ovis and T. annulata, 1 sample with T. lestoquardi and T. annulata, and 4 samples with T. ovis, T. lestoquardi and T. annulata mixed infections were detected.

Conclusion

Ovine theileriosis caused by T. ovis is highly prevalent in southwest Iran while T. lestoquardi and T. annulata infection can be detected in a lesser propor-tion of sheep in this region. The new PCR-RFLP method that was designed in this study, can serve as a beneficial diagnostic tool, especially in T. ovis prevalent re-gions.     

Molecular Survey of Toxoplasma gondii in Sheep,Cattle and Meat Products in Chaharmahal va Bakhtiari Province,Southwest of Iran

Background

Toxoplasmosis is a worldwide spread disease. The present study examined the prevalence of Toxoplasma gondii infection among animals of edible meat (cattle and sheep) in Chaharmahal va Bakhtiari Province (Southwest of Iran) in 2012. Furthermore, we attempted for the first time to identify this parasite from the meat products in the province.

Methods

The tongue, brain, femur muscle and liver of 50 sheep and 70 cattle as well as 50 samples of meat products were selected and collected to perform molecular survey using Nested-PCR method.

Results

Of the studied sheep, 38% were infected. The infection rate in the age groups under 1 year, 1-2 years, and more than 2 years was 25%, 35.29% and 52.94%, respectively. The infection rate in femur muscle, brain, liver and tongue was 28%, 32%, 30% and 16%, respectively. Of the studied cattle, 8.57% were infected. The infection rate in the age groups 1-2 years, 2-4 years, and more than 4 years was 3.7%, 9.09% and 14.28%, respectively. Sheep was infected 6 times more than cattle (OR = 6.53 CI = 2.374-18.005).The infection rate among samples of meat products was 12% (6 samples out of 50 samples).

Conclusion

Due to the high rate of this parasitic infection among the slaughtered animals as well as meat products in this region, the use of infected material can be one of the main risk factors of transmission of the parasite to humans.     

Evaluation of Benzimidazole Resistance in Haemonchus contortus Using Comparative PCR-RFLP Methods

Background

In order to deworm the ruminants especially of sheep in Iran, consumption of benzimidazoles has more than 2 decades history and today farmers are using imidazothiazoles, macrocyclic lactones and mostly benzimidazole compounds (BZs) to treat infected farm animals. It has been demonstrated that the most common molecular mechanism leading to BZsresistance in Haemonchus contortus is a single mutation at amino acid 200 (phenylalanine to tyrosine) of the isotype 1 of beta tubulin gene. According to the report of such mutations in Iranian Teladorsagia circumcincta isolates with Restriction Site Created PCR-RFLP, we decided to evaluate the frequency of such mutations in H. contortus in three different geographical areas of Iran.

Methods

A total of 102 collected adult male H. contortus were evaluated with PCR-RFLP (using PSP1406I as restriction enzyme). By means of a second step to compare function of different methods and to increase sensitivity of detection mechanism, a third of samples were examined by another PCR-RFLP method (using TaaI as restriction enzyme) and finally beta tubulin gene of two samples was sequenced.

Results

All of samples were detected as BZss homozygote. Finally, beta tubulin gene sequencing of two samples showed no point mutation at codon 200.

Conclusion

It seems that BZresistance of H. contortus in Iran is not a serious problem as anticipated before.     

An Epidemiological Survey of Setaria in the Abdominal Cavities of Iranian Sistani and Brahman Cattle in the Southeastern of Iran

Background

In this experiment, abdominal cavity of 518 Iranian Sistani cattle and 498 Brahman cattle were inspected for the presence of Setaria spp. from April 2012 - May 2013.

Methods

The species were determined by microscopic examination of the morphological characteristics of the anterior and posterior parts of the parasites and authentic guidelines.

Results

The overall prevalence of Setaria spp. was 28.6% and 36.5%, respectively and this difference was significant (P<0.05). Out of 148 Sistani cattle which were infected with Setaria, 51(34.4%) were infected with S. digitata, 31 (20.9%) were infected with S. labiatopapillosa, 65 (43.9%) showed mixed infection of S. digitata and S. labiatopapillosa and one case (0.6%) was infected with mixed infection of S. labiatopapillosa, S. digitata and S. marshalli. These values were 87 (47.8%), 27 (14.8%), 67 (36.8%) and 1 (0.5%) for 182 infected Brahaman cows, respectively. The proportion of infected cattle in spring and summer was greater than cooler season (autumn and winter) significantly (P<0.001). The prevalence of infection with Setaria in 2-3 years old Sistatni cattle (42.2 %) was greater than other age categories (P<0.05). Furthermore, the infection rate between males (25.5%) and females (37.3%) Iranian Sistani cattle showed significant difference (P =0.009).

Conclusion

It is important to point out the presence of cerebrospinal setariosis, namely in sheep, goats and horses in the investigated area.     

Detection of Coproantigens by Sandwich ELISA in Rabbits Experimentally Infected with Fasciola gigantica

Background

The study was targeted to report the appearance of coproantigens in feces and circulating antibodies in the serum of Fasciola gigantica experimentally infected rabbits.

Methods

Copro Hyper Immune Serum (HIS) and Excretory-Secretory Hyper Immune Serum (ES HIS) antigens were used in a sandwich ELISA for the detection of F. gigantica antigens in feces of 12 rabbits experimentally infected with different doses of F. gigantica encysted metacercariae (EMC) (10, 25 and 30 EMC). The relation between time of appearance of coproantigens in feces and anti-Fasciola antibodies in serum was evaluated.

Results

The earliest diagnostic coproantigen was recorded at 21^st, 25^th and 28^th day post-infection (p.i.) in groups of rabbits infected with 30, 25 and 10 F. gigantica EMC respectively. Both HIS and ES HIS were able to detect coproantigens in feces of rabbits infected with 30 EMC at day 21 p.i. The appearance of F. gigantica coproantigens in feces of infected rabbits was concurrent to the appearance of anti-Fasciola antibodies in blood (3^rd week p.i.). However, coproantigen has specific ability for direct assessment of active infection with minimal cross-reaction with other heterologous parasitic infections.

Conclusion

The findings hold promise for a more accurate diagnostic technique in the near future for suspected Fasciola infection.     

Comparison of a Commercial ELISA with the Modified Agglutination Test for Detection of Toxoplasma gondii Antibodies in Sera of Naturally Infected Dogs and Cats

Background

Toxoplasma gondii can infect all warm-blooded animals. Modified agglutination test (MAT) and ELISA are widely used for the detection of T. gondii antibodies. However, there is little information on their acceptability for detecting antibodies in companion animals.

Methods

This study compared ELISA and MAT for their ability to detect T. gondii infection in naturally infected dogs and cats. Blood samples were collected from dogs and cats in different areas of Beijing, China and analyzed by ELISA and MAT. The χ² test and κ analysis were used to evaluate their efficiency and agreement.

Results

For dogs, the seroprevalence of T. gondii antibodies detected by ELISA was 34.7%, which was significantly higher than that detected by MAT (P<0.05). There was no significant difference between ELISA and MAT for detecting T. gondii antibodies in cats. Good agreements between MAT and ELISA were seen in both dogs and cats; however, inconsistent results were demonstrated by κ analysis and in MAT titer assay.

Conclusion

Serum-based ELISA may be more satisfactory for screening test of T. gondii infection in dogs, whereas both methods could be acceptable in cats.     

Genetic Diversity of Human Blastocystis Isolates in Khorramabad,Central Iran

Background

There are some genetic differences in Blastocystis that show the existence of species or genotypes. One of these genes that help in identifying Blastocystis is SSUrRNA. The aim of this study was assessment of genetic diversity of Blastocystis by PCR with seven pairs of STS primers.

Methods

This study was done on 511 stool samples collected from patients referred to the health care centers of Khorramabad, Central Iran, in 2012. Genomic DNA was extracted and in order to determine the Blastocystis subtype in contaminated samples, seven pairs of primers STS (subtype specific sequence-tagged site) were used.

Results

Out of 511 samples, 33 (6.5%) samples were infected with Blastocystis. Subtype (ST) of 30 samples was identified and three subtypes 2, 3 and 4 were determined. Mix infection was reported 10% which 3.33% of the infection was for the mixture of ST 3 and ST5 and 6.67% was for the mixture of ST 2 and ST 3.

Conclusion

The predominant subtype was ST3 that is the main human subtype. The dominance of ST2 and 5 are important in this study. This superiority has been reported in some of the studies in ST 2 which is different from the studies in other countries, because they have announced priorities of the ST1 and ST6 after ST3.     

Induction of Oxidative Stress in Skin and Lung of Infected BALB/C Mice with Iranian Strain of Leishmania major (MRHO/IR/75/ER)

Background

The aim of this study was to investigate the effects of Leishmania major infection on the induction of oxidative stress in skin and lung of female mice.

Methods

BALB/c mice were randomly divided into the control and experimental groups. The experimental groups were subcutaneously infected with inoculums promastigotes of L. major. The animals were sacrificed at 20, 40, 60, 90 and 120 days post-infection, and tissues were isolated and analyzed.

Results

Superoxide dismutase activity, percent of DNA fragmentation and superoxide anion production levels were increased in skin and lung of infected mice. Lung catalase activity and skin malondialdehyde level were also increased. The decreased glutathione level was observed in both tissues. The highest alteration in these parameters in both tissues was observed at 90 days post-infection.

Conclusion

L. major infection induces the production of free radicals and oxidative stress in a time-dependent manner in mice skin and lung by depletion of glutathione and increasing lipid peroxidation. The elevated DNA fragmentation may be related with increased oxidative stress. The skin is more sensitive to the effects of L. major infection on oxidative stress induction compared to the lung.     

Potentially Pathogenic Free-Living Amoebae in Contact Lenses of the Asymptomatic Contact Lens Wearers

Background

Free-living amoebae (FLA) including Acanthamoeba spp. and Hartmannella spp. are the causative agents of serious corneal infection especially within contact lens wearers. Thus contact lenses and their storage case could be a suitable niche for potentially pathogenic amoebae. The main objective of the present study was to evaluate the contamination of contact lenses to free living amoebae using morphological and sequencing based methods.

Methods

Overall, 90 volunteers provided their contact lenses. All volunteers wore soft contact lenses. Both lenses were cultured in the same plate. Forty-eight of the volunteers were medical and dentistry student and 42 were ophthalmology attendees of hospitals in Tehran, Iran. All of the samples were inoculated to non-nutrient medium and monitored daily for the outgrowth of the amoebae. PCR and sequencing were performed using various primer pairs.

Results

Of the 90 volunteers, 9 (10%) were positive for free-living amoebae outgrowth. Morphological analysis revealed that 3 isolates were belonged to Hartmannella genus according to small round cysts and 6 isolates were belonged to Acanthamoeba genus based on the star shape of endocysts. Sequencing revealed that Acanthamoeba belonged to T4, T3 and T5 genotype. Hartmannella were also belonged to vermiformis species.

Discussion

The presence of potentially pathogenic free living amoebae including Acanthamoeba and Hartmannella could be a high risk for people using soft contact lenses. These results revealed that improved clarification and professional recommendations for contact lens wearers is of utmost importance.