Entamoeba histolytica , the causative agent of intestinal and extraintestinal amebiasis, is a common parasitic cause of significant morbidity and mortality in the developing countries. Hence, early detection and differentiation of pathogenic E. histolytica from nonpathogenic/commensal Entamoeba spp (Entamoeba dispar/Entamoeba moshkovskii/Entamoeba bangladeshi) plays a crucial role in clinical management of patients with amebiasis. Most diagnostic tests currently available do not reliably differentiate between the species of Entamoeba and are less sensitive, cumbersome to perform. Molecular-based methods are highly sensitive, easy to perform and differentiates the pathogenic Entamoeba from nonpathogenic species, serving the criteria for an ideal diagnostic test for amebiasis. Recently, microarray technology has been found to be a promising tool for the diagnostic and epidemiological evaluation of amebiasis.

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Parasite cultivation techniques constitute a substantial segment of present-day study of parasites, especially of protozoa. Success in establishing in vitro and in vivo culture of parasites not only allows their physiology, behavior and metabolism to be studied dynamically, but also allows the nature of the antigenic molecules in the excretory and secretory products to be vigorously pursued and analyzed. The complex life-cycles of various parasites having different stages and host species requirements, particularly in the case of parasitic helminths, often make parasite cultivation an uphill assignment. Culturing of parasites depends on the combined expertise of all types of microbiological cultures. Different parasites require different cultivation conditions such as nutrients, temperature and even incubation conditions. Cultivation is an important method for diagnosis of many clinically important parasites, for example, Entamoeba histolytica, Trichomonas vaginalis, Leishmania spp., Strongyloides stercoralis and free-living amoebae. Many commercial systems like InPouch TV for T. vaginalis, microaerophilous stationary phase culture for Babesia bovis and Harada-Mori culture technique for larval-stage nematodes have been developed for the rapid diagnosis of the parasitic infections. Cultivation also has immense utility in the production of vaccines, testing vaccine efficacy, and antigen - production for obtaining serological reagents, detection of drug-resistance, screening of potential therapeutic agents and conducting epidemiological studies. Though in vitro cultivation techniques are used more often compared with in vivo techniques, the in vivo techniques are sometimes used for diagnosing some parasitic infections such as trypanosomiasis and toxoplasmosis. Parasite cultivation continues to be a challenging diagnostic option. This review provides an overview of intricacies of parasitic culture and update on popular methods used for cultivating parasites.

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Filariasis is traditionally diagnosed following screening of peripheral smear for microfilaria. Clinically lymphatic filariasis mimics the common local diseases. Thus, it is plausible to observe this parasitic infection in histological sections. We encountered three such cases, which displayed diverse patterns of immune response. Presence of both dead and viable worm at the same foci suggests that such immune response could be the result of parasitic death. Histological features such as endothelial injury and granulomatous response attests to the role of Wolbachia bacteria in influencing tissue response.

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Informed consent is the central doctrine to any research based on the principles of autonomy and self-determination. For it to be genuine and effective, it should be in simple regional language catering to the cultural and psychological and social requisites of the participant. The information entailed in the consent form must be true, should cover all the relevant aspects, and no fact should be hidden however seemingly important or unimportant. Every research volunteer puts his or her health and life at risk for the sake of science, and this must be respected at all times during the research.

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Rational: The role of Cryptosporidium as an agent of human diarrhea has been redefined over the past decade following recognition of the strong association between cases of cryptosporidiosis and immune deficient individuals (such as those with AIDS). Purpose: The purpose of this study is to determine the prevalence of enteric parasites and to compare the diagnostic utility of stool enzyme-linked immunosorbent assay (ELISA) with various modifications of acid-fast (AF) staining in detection of Cryptosporidium in stool samples of diarrheic patients. Materials and Methods: Stool samples from 186 cases comprising of 93 HIV seropositive and 93 seronegative patients were included. These were subjected to routine and microscopic examination as well as various modifications of AF staining for detection of coccidian parasites and ELISA for the detection of Cryptosporidium. Results: The prevalence of enteric parasites was 54.8% and of Cryptosporidium was 17.2% in HIV seropositive patients while it was 29.0% and 5.4%, respectively in seronegative patients. Of the 186 cases, 33 cases (17.7%) were positive for Cryptosporidium by stool ELISA as compared to 21 (11.3%) by modified AF staining (gold standard) showing sensitivity and specificity of 100% and 92.7%, respectively. The maximum cases of Cryptosporidium (21; 11.3%) were detected by AF staining using 3% acid alcohol. Conclusion: ELISA is a simple, useful, and rapid tool for detection of Cryptosporidium in stool, especially for large scale population studies. However, the role of modified AF staining in detection of Cryptosporidium and other coccidian parasites is important. Based on the results of various modifications of AF staining, the present study recommends the use of 3% acid alcohol along with 10% H ₂ SO ₄ .

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Molecular tools have the potential to differentiate microscopically similar gut micro-eukaryotes that may have significantly different relationships with the human host. Using broad range Entamoeba primers to amplify a section of the eukaryotic 18S small subunit ribosomal RNA gene a novel member of the Entamoeba family (Entamoeba bangladeshi) has recently been identified. The goal of this review is to place this species in the context of what is already known about this genus and to discuss the tools and data needed to elucidate the host-microbe relationship.

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A 30-year-old manual laborer from Karnataka, India presented with intermittent low grade fever and diffuse headache for 1 month. On examination, patient had enlarged supraclavicular and cervical lymph nodes. Patient had positive Kernig's sign and neck stiffness. Motor, sensory and cranial nerve examinations were within the normal limits. Abdominal, cardiovascular and chest examination did not yield any positive findings. Contrast enhanced computed tomography head was normal. Patient was suspected to have extrapulmonary tuberculosis. Patient was started on antitubercular drugs. Diagnostic lumbar puncture was performed. Wet mount and Giemsa smear preparation of cerebrospinal fluid (CSF) showed trophozoites suggestive of Acanthamoeba. CSF was cultured onto non-nutrient agar with an overlay of Escherichia coli. Wet mount made from the culture media yielded cysts and trophozoites of Acanthamoeba spp. Patient was diagnosed with Acanthamoeba meningitis and was started on specific therapy with Rifampicin 600 mg once a day, Cotrimoxazole 960 mg twice-a-day and Fluconazole 400 mg once daily for 2 weeks. Patient had a complete recovery and was discharged from the hospital.

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Background and Objectives: Infection with Plasmodium falciparum, caused 627,000 deaths in 2012 in the world. P. falciparum infection causes myriads of clinical manifestations. Exact clinical manifestation resulting in poor prognosis in hyper-endemic epidemiological settings need to be ascertained to save human lives. A hospital-based study was conducted to elucidate the different severe clinical presentations of falciparum malaria and to examine the critical clinical and laboratory parameters on the prognosis of these severe manifestations in a stable hyper-endemic falciparum area in the state of Odisha, India. Materials and Methods: Consecutive patients admitted in a tertiary care hospital with severe manifestations of malaria as per WHO criteria and confirmed by parasitological examination were included in the study. A detailed clinical and biochemical parameters were examined. Clinical data were reviewed before being double entered into a computer and analyzed. Statistical analyses were carried out using Epi Info 6.04. Continuous and normal distributed data were compared by two-tailed Student's t-test and proportions compared with χ² tests with Yates' correction or Fisher's exact test. Results and Discussion: A total of 1320 patients with clinical malaria, diagnosed at outpatients' department were admitted in the hospital during the 1 year study period of which, 292 (22.1%) were children under 14 years of age. The major clinical categories on admission were hyperpyrexia (70.7%), cerebral malaria (9.4%), malarial anemia (7.7%), algid malaria (1.5%), and malaria associated categories were respiratory infection (2.2%), hepatitis (2.0%), urinary tract infection (1.8%), enteric fever (3.3%), and sickle cell disease (1.2%). The overall case fatality rate (CFR) was 4.3 (57/1320). The CFR in children 12.3 (36/292) was significantly higher when compared to adults, that is, 2.0 (21/1028). The major causes of death were cerebral malaria (45.6%), malaria along with a respiratory infection (19.3%) and anemia (10.5%). Malarial anemia along sickle cell disease accounted for 19.3% of all malaria related deaths. Proportion of mortality due to acute renal failure was higher in adults. Biochemical parameters suggest involvement of multiple organs. The findings suggest that the area can be effectively managed by sustained and continuous preventive and curative efforts.

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Entamoeba histolytica is a major cause of diarrhea in the developing countries and it can present with a wide range of gastrointestinal symptoms depending on the phase of the infection. We describe a case of 65-year-old male patient presented with abdominal pain and vomiting. On the clinical and radiological examination provisional diagnosis of colonic carcinoma was suspected. After resection of perforated caecal growth, histopathological sections showed numerous trophozoites of E. histolytica in a background of abundant necrosis. This case revealed differentiation between amoeboma and carcinoma is critical.

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Human dirofilariasis is an uncommon zoonotic parasitic infection caused by species of the genus Dirofilaria. Location of the worm is usually confined to the subcutaneous tissues of eyelids, fingers, cheeks and breasts. Ophthalmic involvement is usually periorbital, intraocular or of the eyelids. Subconjunctival localization is rarely observed. We report three cases of subconjunctival dirofilariasis in males, age ranges between 45 and 60 years. All the cases were caused by Dirofilaria repens. The worms were surgically removed under local anesthesia. The cases are discussed in the light of earlier reports on subconjunctival dirofilariasis. In view of frequent reports of dirofilariasis from Karnataka, considering the state endemic for dirofilarasis is also discussed.

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Introduction: Chagas disease is a zoonotic disease caused by Trypanosoma cruzi and dogs are one of the main domestic reservoirs. Materials and Methods: One molecular (OligoC-TesT, Coris Bioconcept) and one serological (T. cruzi-Detect, Inbios) rapid tests were evaluated as infection markers for T. cruzi in 102 dogs living in eight villages endemic for Chagas in Costa Rica. Results: T. cruzi-Detect performed well as screening tool with 23.3% positive samples. The large number of invalid results (66.7%) observed in samples tested with OligoC-TesT precluded assessing the use of this new method as epidemiological tool to detect T. cruzi infection in dogs.

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Cryptosporidium species is identified as an important cause of morbidity in children and adults. Prevalence rate as reported from various studies in India is much lower when compared to developed word. Present study was designed to analyze the prevalence of cryptosporidiosis in West Godavari District, Andhra Pradesh. Stool samples from 306 patients suffering with gastrointestinal symptoms were examined for the presence of Cryptosporidium oocysts. A higher prevalence (25%) was found when compared to reports from north east and western India. Cryptosporidium was prevalent in 35-36% of adults, 17% of children and 20% of infants.

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