Protozoa of the genus Giardia lamblia lives in proximal part of the small intestine of humans and causes disturbance, disease and malabsorption, especially in children. Since this protozoa is one of the most prevalent pathogens in humans and is very important in the field of medicine, therefore, investigation about this parasite is necessary. Biological study of protozoa needs in vitro culture of trophozoites. Due to the development of serological tests and need for parasite antigens, in vitro cultivation of trophozoite is warranted. In this study, RPMI 1640 culture medium was used for Giardia growth and reproduction. Giardia cysts were purified by the four - layer sucrose method. After induction by acid solution, cycts were transferred to culture tubes and incubated in 370C. After 24 hours, samples were checked once a day for one week. From 53 culture samples,Giardia lamblia trophozoite was seen in 25 samples. Reproduction of protozoa in a large scale was not possible for a long time. Mean period of trophozoite viability was found to be 38.6 hours. Results of this study demonstrated that RPMI 1640 can be used for Giardia excystation and maintenance, but it is necessary to add other nutritional materials for reproduction and passage of trophozoites.

Background: Giardia lamblia and Helicobacter pylori are two flagellate microorganisms that grow in duodenum and stomach. The aim of this study was to evaluate the prevalence of them in patients with dyspepsia and other GI disorders. Methods: In this cross-sectional study, co-infection of above-mentioned agents was investigated in a group of 130 patients [median age of 40 yr (range=11-79) including 76 males (58.8%)] with dyspepsia using three methods of duodenal aspiration sample, duodenal biopsy samples and evaluation of stool samples.Results: : From 105 patients (59 males, 46 females, median age 40 years, range 11-79) entering this study from 3 hospitals, 4 patients (3.8%) had G. lamblia and 61 patients (58%) had H. pylori. All 4 patients infected by Giardia had also H. pylori infection. Tenesmus (3 out of 4 patients) was the most common symptom in patients with H. pylori infection (48 out of 61 patients) was reflux. Other symptoms in patients infected with both organisms (4 patients) included diarrhea (2 cases), weight loss (2 cases), and loss of appetite (1 case) but no report of vomiting.Conclusion: In patients co-infected with Giardia, H.pylori differentiation by physical examination is not possible. So in those patients with positive Rapid Urease Test (RUT), stool examination for Giardia detection is recommended. In addition, metronidazole (broad spectrum, anti-protozoal drug) can be useful in H. pylori infection.

Giardiasis has a global distribution and it is a common cause of diarrhea in both children and adults and is transmitted via the fecal-oral route through direct or indirect ingestion of cysts. The laboratory diagnosis of Giardia spp. is mainly based on demonstration of microscopic cyst or trophozoite in stool samples but several immunological-based assays and molecular methods are also available for Giardiasis diagnosis. The aim of this study was to conduct a review of the applied methods in medical laboratory and to highlight pitfalls and challenges of them for diagnosis of Giardiasis. In this article we have evaluated the Giardia diagnostic methods with a broad review of literature, electronic databases and books. The search has covered the articles and some textbooks that have published up to 2018. It has been concluded that traditional microscopy combination with stool concentration method should still be held in the routine medical laboratory due to economical and high sensitivity and immunological-based assay and molecular methods which are recommended to use as a complementary test to the traditional technique.

Introduction: Giardia lamblia is the most frequently human intestinal protozoan in the worldwide. Diagnosis of G. lamblia by microscopic examination of stool is common. ELISA & IFA methods have researching and epidemiological use. For designing a powerful test with high detection rate like dipstick or rapid diagnosis kits; first step is production of polyclonal antibody. For this reason we decided to produce polyclonal antibody against G lamblia in rabbit.Material and methods: Giardia cysts were purified from human fecal samples by sucrose two stages modified gradient method. Their concentration was independently adjusted to 1× 106/ml PBS, were inoculated intramasculary-intradermaly in four stage with freunds complete adjuvant for first time and with freunds adjuvant for second time and without freunds adjuvant for next time, in rabbit. After immunization of rabbit, IFA test was carried out to evaluate the polyclonal antibody production against Giardia.Results: The results of test showed the rabbit was immuned. Best results of IFA were achieved with 1×106/ml parasite and sera dilution of 1/100 and goat anti rabbit IgG conjugated with FITC dilution of 1/20 is under immunofloursent microscope.Conclusion: Giardias antigens have an important role for diagnosis in clinical and other samples. Production of anti Giardia polyclonal antibody with high titer is first and important step for designing IFA and direct ELISA kits for direct detection of Giardias antigens. Produced polyclonal antibody can use purification and conjugation with enzyme.

Introduction. Giardiasis is one of the health problems in the world including Iran. To determine the biochemical and biological problems and also identification of various strains, it is essential to obtain pure culture and then mass production of Giardia lamblia. The goal of this study was to isolate this protozoa purely.Methods. Giardia lamblia cysts were isolated from 50 stool samples by use of floating of a four - layer of sucrose method. The cysts were transfered to an inducing solution. Subsequently, they were cultured in a modified culture medium (TYIS-33). Following excystation of trophozoite and its multiplication, the parasite was caltured and purified.Findings. Excitation of trophozoite was observed in 40 samples (80 percent) from which 22 samples (55 percent) yielded pure culture. The doubling time was approximately 13hr and the peak of parasite was observed between third and fourth days.Conclusion. The proliferation and growth rate of Giardia lamblia have enabled us to use this method widely. Cystein and ascorbic acid which are present in the induction solution, have a key role in excystation of trophozoite. Purification and passage of samples has facilitated the culture of this parasite in vitro. Therefore this method has yielded better results in comparison with other studies. This is probably due to a decrease in the amount of bovine bile or using different strains of Giardia lamblia in the present study.

Giardiasis is one of the parasitic diseases with gastroenteritis caused by unicellular Giardia lamblia. Infection is occurred mainly by contaminated water, food or raw vegetables with cysts which are excreted by human source. Blastocystis hominis is a micro-organism living in human large intestine and may lead to variable gastroenteritis. High humidity, ecological conditions, superficial water, domestic and industrial animal husbandry and the rate of raining made Tonekabon city as specific and Mazandaran as a Province for transmission of parasitic diseases. In this study, simultaneous prevalence of Blastocystis hominisin patients with Giardiasis was investigated between 2007 to 2008 in Tonekabon city, which is located in western part of Mazandaran Province, Northern Iran. Overall, 226 stool samples of gastroenteritic patients were collected, fixed and examined by Direct Method (DM) and concentration with Paraseb Kit for diagnosis of enteropathogenic parasites. The results confirmed the prevalence rates of G. lamblia and Blastocystis hominis among patients with gastroenteritis were 3.54% and 3.1% respectively, however coinfection of both microorganisms was observed in 66.7% of them simultaneously. It is indicated here, simultaneous co-infections of G. lamblia with B. hominis may facilitate reproduction of Blastocystis and increase pathogenesis of Giardiasis in infected patients.

Introduction: Giardia lamblia is one of the most prevalent flagellate protozoa in human with the world-wide distribution. Millions of people are affected by Giardiasis annually. Today, many treatments are available for Giardiasis that associated with some side effects. This study is aimed to evaluate the antiGiardial activity of Lavandula angustifolia in vivo.Materials and Methods: In this study 25 mice are categorized in 5 groups include; Control group (without any treatment), Positive control (treatment by Metronidazole) and other three groups (treatment by 100, 200 and 400 mg/ml of Plant extracts). Then, after 10 days, the effects of each group are evaluated on the Giardia lamblia. The statistical methods used were based on one-way variance analysis and paired t-comparison that were used in the usual way for normal values in the Bootstrap method for values that were not distributed normalized according to the low sample size.Results: In this study, the body weights of treated mice with different extracts were more than the positive control and less than the negative control. Also, the live cysts were decreased 77.7, 83.4 and 95.1% by the use of 100, 200 and 400 mg/ml of plant extracts.Conclusion: The results of the current study indicated that Lavandula angustifolia has conceivable effects in vivo and it will be a suitable alternative for treatment of Giardiasis.

Introduction: Giardia lamblia is an important and prevalent parasitic cause of diarrhea and gastroenteritis. Regarding the significance of Giardiasis treatment particularly by medicinal plants and G. lamblia resistance to chemical drugs, this study was conducted to study in vitro effect of Valeriana officinalis hydro alcoholic extract on G. lamblia cysts.Methods: In this experimental, laboratory study the hydro alcoholic extract of V. officinal is at concentrations of 12.5, 25, 50, 100, and 200 mg/mL was applied on G. lamblia cysts. The findings were compared with controls.Results: Mean results of the effect of V. officinal is hydro alcoholic extract at different concentrations on G. lamblia cysts after 1, 6 and 24 hours demonstrated that the extract at all concentrations caused a notable decrease in alive cysts, with more intensive effect at 100 and 200 mg/mL concentrations and 100% fatality after 1 hour. As the extract concentration decreased, the speed of G. lamblia cysts inhibition declined.Conclusion: V. officinal is hydro alcoholic extract might be recommended as an effective compound for removing G. lamblia protozoan cysts, although further studies are needed to show this effect on human.