Highlights of human toxocariasis

Environmental contamination with Toxocara spp. eggs in public parks and playground sandpits of Greater Lisbon, Portugal

Toxocarosis is a zoonotic parasitic disease transmitted from companion animals to humans. Environmental contamination with Toxocara eggs is considered to be the main source of human infections. In Portugal, knowledge regarding the current situation, including density, distribution and environmental contamination by Toxocara spp., is largely unknown. The present study investigated environmental contamination with Toxocara spp. eggs, in soil and faecal samples collected from public parks and playground sandpits in Greater Lisbon, Portugal. A total of 151 soil samples and 135 canine faecal samples were collected from 7 public sandpits and 12 public parks, over a 4 month-period. Soil samples were tested by a modified centrifugation and sedimentation/flotation technique and faecal samples were tested by an adaptation of the Cornell-Wisconsin method. Molecular analysis and sequencing were performed to discriminate Toxocara species in the soil. Overall, 85.7% of the sandpits (6/7) and 50.0% of the parks (6/12) were contaminated with Toxocara spp. eggs. The molecular analysis of soil samples showed that, 85.5% of the sandpits and 34.4% of the parks were contaminated with Toxocara cati eggs. Faecal analysis showed that 12.5% of the sandpits and 3.9% of the parks contained Toxocara canis eggs. In total, 53.0% of soil and 5.9% of faecal samples were positive for Toxocara spp. Additionally, 56.0% of the eggs recovered from the samples were embryonated after 60 days of incubation, therefore considered viable and infective. The average density was 4.2 eggs per hundred grams of soil. Public parks and playground sandpits in the Lisbon area were found to be heavily contaminated with T. cati eggs, representing a serious menace to public health as the studied areas represent common places where people of all ages, particularly children, recreate. This study sounds an alarm bell regarding the necessity to undertake effective measures such as reduction of stray animals, active faecal collection by pet owners, awareness campaigns and control strategies to decrease the high risk to both animal and human health.

Abnormal neurobehaviour and impaired memory function as a consequence of Toxocara canis- as well as Toxocara cati-induced neurotoxocarosis

BACKGROUND

Neuroinvasive larvae of the worldwide occurring zoonotic roundworms Toxocara canis and T. cati may induce neurotoxocarosis (NT) in humans, provoking a variety of symptoms including cognitive deficits as well as neurological dysfunctions. An association with neuropsychological disorders has been discussed. Similar symptoms have been described in T. canis-infected mice, whereas data on T. cati-induced NT are rare. Therefore, it was aimed to obtain insights into the impact on neurobehaviour as well as progression of neurological symptoms and behavioural alterations during the course of NT directly comparing T. canis- and T. cati-infected mice as models for human NT.

METHODOLOGY/PRINCIPAL FINDINGS

C57BL/6 mice were orally infected with 2000 embryonated T. canis or T. cati eggs, respectively, the control group received tap water. Mice were screened weekly for neurobehavioural alterations and memory function starting one day prior infection until 97 days post infection (pi; T. canis-infection) and day 118 pi (T. cati-infection, uninfected control). Mostly motoric and neurological parameters were affected in T. canis-infected mice starting day 20 pi with severe progression accompanied by stereotypical circling. In contrast, T. cati-infected mice mostly showed reduced response to sudden sound stimulus (indicator for excitability) and flight behaviour starting day 6 pi. Interestingly, enhanced grooming behaviour was observed exclusively in T. cati-infected mice, indicating a possible role of neurotransmitter dysregulation. Reduced exploratory behaviour and memory impairment was observed in both infection groups with delayed onset and less severe progression in T. cati- compared to T. canis-infected mice.

CONCLUSIONS/SIGNIFICANCE

Results highlight the need to consider T. cati beside T. canis as causative agent of human NT. Findings provide valuable hints towards differences in key regulatory mechanisms during T. canis- and T. cati-induced NT, contributing to a comprehensive picture and consequently a broader understanding of NT, which will aid in developing strategies towards prevention in addition to novel diagnostic and therapeutic approaches.

Sanitation for all: the global opportunity to increase transgenerational health gains and better understand the link between NCDs and NTDs, a scoping review

The global sanitation divide is narrowing. However, in many countries in Asia and Africa, the gap between rural and urban sanitation coverage is rather widening. Moreover, there is an increase in the burden of non-communicable diseases (NCDs), notwithstanding to the already high burden of neglected tropical diseases (NTDs). A scientific query is building on how the global 'sanitation for all' goal will address the dual burden of NTDs and NCDs, and help further understand the link between the two. This paper aims to discuss the link between i) sanitation and NTDs, and ii) sanitation and NCDs through a scoping review of the literature.

Dot enzyme-linked immunosorbent assay (ELISA) for the detection of Toxocara infection using a rat model

Toxocariasis is a zoonotic disease usually caused by dog and cat roundworms, Toxocara canis and T. cati. Detection and diagnosis is difficult in paratenic and accidental hosts, including humans, as they cannot be detected through conventional methods such as fecal examination. Diagnosis therefore relies on immunological methods and molecular methods such as enzyme-linked immunosorbent assay (ELISA) and Western Blot, which are both time-consuming and requires sophisticated equipment. In the Philippines, only a few studies are available on Toxocara seroprevalence. Therefore, there is a need to adapt methods for serodiagnosis of Toxocara infection in humans for the Philippine setting. A dot enzyme linked immunosorbent assay (dot-ELISA) was standardized using T. canis excretory-secretory antigens. Test sera were collected from laboratory rats (Sprague-Dawley strain) experimentally infected with embryonated eggs of T. canis and Ascaris suum as well as rice field rats naturally infected with Taenia taeniaeformis and Nippostrongylus sp. Optimum conditions used were 20 µg/ml antigen concentration and 1:10 serum dilution. The sensitivity, specificity, positive, and negative predictive values were 90% (95% CI 55.5-99.7%), 100% (95% CI 69.2-100.0%), 100% (95% CI 66.4-100%), and 90.9% (95% CI 58.7-99.8%), respectively. Dot-ELISA has the potential to be developed as a cheaper, simpler, and more practical method for detection of anti-Toxocara antibodies on accidental hosts. This is a preliminary study conducted on experimental animals before optimization and standardization for human serum samples.

Global toxocariasis research trends from 1932 to 2015: a bibliometric analysis

BACKGROUND

Toxocariasis is a highly prevalent parasitic disease in the tropical regions of the world, with its impact on public health being typically underestimated. To better recognise the trends and characteristics of toxocariasis research, this study is a bibliometric analysis of the global toxocariasis research.

METHODS

Searches were completed on April 5, 2016, using the Scopus database. A search without any language restriction was performed to extract publications dealing with toxocariasis. Terms related to toxocariasis were used to perform a title keyword search.

RESULTS

A total of 2765 publications comprising 11 document types and published between 1932 and 2015 were included in the analysis. Articles were the most popular document form, accounting for 83.62% of all publications, followed by letters (3.80%) and reviews (3.4%). The annual number of research publications increased from 30 in 1980 to 111 in 2015, indicating that the number of publications on toxocariasis has increased slowly over the past 35 years. The United States of America and Japan are the predominant countries of origin, with 303 articles and 207 articles, respectively, followed by Brazil and the United Kingdom, with 180 (6.5%) each. The h-index for all the publications was 60. The highest h-index were for publications from the United Kingdom (h-index value = 43) and the United States (h-index value = 39); these two countries were also involved with the highest number of international collaborations, with 27 and 28 countries, respectively.

CONCLUSIONS

Developed countries, including the United States, Japan, the United Kingdom, France, Germany and Italy, are the world's leaders in toxocariasis research, contributing to more than 34% of the total published literature. In addition, developing countries, such as Brazil, Poland, Argentina and India, showed a noticeable increase in published papers on toxocariasis research in recent years. A push for more collaboration is needed to achieve a superior research strategy related to toxocariasis at the global level from the viewpoint of epidemiological data, clinical aspects, medical ecology, molecular aspects and treatment practices associated with toxocariasis.

Enhanced resolution of eosinophilic liver abscess associated with toxocariasis by albendazole treatment

BACKGROUND/AIMS

Visceral larva migrans, caused by Toxocara canis and Toxocara cati, has emerged as a significant cause of eosinophilic liver abscess (ELA). Differentiation of ELA associated with toxocariasis (ELA-T) from metastasis or primary liver malignancy is sometimes difficult. However, the role of albendazole treatment remains uncertain in this condition. The aim of this study was to evaluate whether albendazole can enhance the radiologic resolution of ELA-T.

METHODS

We retrospectively reviewed the medical records of the patients diagnosed with ELA-T at our institution between January 2008 and December 2011. ELA-T was diagnosed based on the imaging findings on computed tomography or magnetic resonance imaging and the presence of positive serum IgG antibody for Toxocara canis. Among a total of 163 patients, 32 patients received albendazole (albendazole group) and 131 did not (control group). Baseline characteristics and fate of liver nodules were compared between the two groups.

RESULTS

Baseline characteristics (age, sex, number and maximal size of lesions, eosinophil count) were similar between the two groups. Median duration for achieving radiologic resolution in the albendazole group was significantly shorter than in the control group (207 days [range 186-228] vs. 302 days [range 224-380], p=0.023). In Cox regression analysis of the cumulative rates of radiologic resolution, the hazard ratio for albendazole treatment was 1.99 (95% confidence interval, 1.22-3.23).

CONCLUSIONS

Radiologic resolution of ELA-T can be accelerated with albendazole treatment. Hence, inconvenience associated with long-term follow-up and unnecessary worries among patients can be eliminated with albendazole treatment.

Trend of toxocariasis in Iran: a review on human and animal dimensions

One of the neglected soil and/or food-borne diseases with international public health importance is toxocariasis. Human cases are being increasingly reported from Asian, African, Oceania, European and the American countries. Hence, human toxocariasis (HT) is now considered as a major zoonosis with global and regional importance. In Iran, human and animal toxocariasis is an endemic disease with clinical and epidemiologic health problem aspects. Doubtless, understanding the epidemiology and the trend of this important parasitic disease and its affecting factors will provide the establishment of effective prevention and control programs. To better understand the trend of toxocariasis researches in Iran, this study was performed to analyze different aspects of this zoonotic disease including history, life cycle, species, human animals and environmental studies, diagnostic aspects and treatments to find out the gaps, including different aspects of clinical sings in human patients, new and specific recombinant antigens based on the native antigens, new diagnostic tools, especially rapid diagnostic tests, paratenic hosts status and new treatment procedures which is necessary to be investigated in the future studies on this important zoonotic disease.

Characterization of the parasite-induced lesions in the posterior segment of the eye

Ocular lesions are frequently associated with different parasitic infections. The classes of infection include protozoa, nematodes, cestodes, and ectoparasites. Ocular parasitic infections can manifest in any part of the eye; the disease manifestations are frequently characterized as either posterior or anterior eye disease. Parasite-induced lesions may be due to damage directly caused by the parasite, indirect pathology caused by toxic products or the immune response initiated by infectious parasitism. This review characterized the parasite-induced lesions in the posterior segment of the eye. Prompt diagnosis and early treatment of these lesions can reduce ocular morbidity. The method of the literature search was conducted on PubMed, Elsevier Scopus database, and Google Scholar with no limitation on the year of publication databases. It was limited to English articles published for ocular lesions in clinical studies and was focused on parasitic infections of the eye.

Kinetic and avidity of IgY anti-Toxocara antibodies in experimentally infected chickens

Toxocariasis is a geohelminth zoonosis with worldwide distribution, mainly transmitted through the ingestion of embryonated eggs of nematodes of the Toxocara genus. The disease can also be transmitted to humans as a result of eating raw or undercooked meat of paratenic hosts, such as chickens. Here, we standardized an enzyme-linked immunosorbent assay (ELISA) for evaluating experimentally the kinetic and avidity index (AI) of IgY in broiler chickens infected with different doses of Toxocara canis eggs (G1:100; G2: 1000; and G3: 5000; n = 12 per group). The test showed 91.7% sensitivity (CI 95%: 77.5-98.3) and 100% specificity (CI 95%: 92.6-100), and highest efficiency (97.0%) at 60 days post infection. Infection was characterized by the presence of high avidity antibodies in the chronic phase. Our results support that the ELISA can be a highly useful tool for the detection of anti-Toxocara antibodies in chickens.

Human Toxocariasis: Prevalence and Factors Associated with Biosafety in Research Laboratories

Human toxocariasis is a neglected parasitic disease worldwide. Researchers studying this disease use infectious strains of Toxocara for experiments. Health workers are at risk in the course of their daily routine and must adhere to biosafety standards while carrying out the activities. Researchers on biosafety concerning working with these parasites are insufficient. The aim of this study was to determine the rate of seroprevalence of Toxocara species among health-care research laboratory workers (professors, technicians, and students), and to investigate the risk factors of Toxocara infection associated with laboratory practices. This cross-sectional study involved 74 researchers at two federal universities in southern Brazil from February 2014 to February 2015; 29 researchers manipulated infective strains of Toxocara canis (test group) and 45 did not (control group). Serum samples were examined using enzyme-linked immunosorbent assay. Epidemiological data were obtained via a questionnaire containing information about laboratory routine, eating behavior, and contact with dogs. The seroprevalence of anti-T. canis IgG was 14.9% (11/74; 13.8% [4/29] in the test group and 15.6% [7/45] in the control group). Most individuals in the test group correctly understood the primary mode of infection; however, 13.8% did not use gloves while manipulating T. canis eggs. Knowledge of biosafety must be well understood by health-care professionals doing laboratory work with biological agents. To our knowledge, this is the first study to investigate the rate of seroprevalence of IgG against Toxocara spp. among professionals and students who handle infective forms of the nematode T. canis.

In vitro production of Toxocara canis excretory-secretory (TES) antigen

Toxocara canis is a widespread gastrointestinal nematode parasite of dogs and cause Toxocara larva migrans, an important zoonotic disease in humans on ingestion of infective eggs. Toxocarosis is one of the few human parasitic diseases whose serodiagnosis uses a standardized antigen, T. canis excretory secretory antigen (TES). The present study describes collection of T. canis adult worm, collection and embryonation of T. canis eggs, hatching and separation of T. canis larvae, in vitro maintenance of T. canis second stage larvae for production of TES, concentration of culture fluid TES and yield of TES in correlation with various methods cited in literature.

Production of interleukins 4 and 10 in children with hepatic involvement in the course of Toxocara spp. infection

Toxocara spp. infestations present with a wide spectrum of symptoms, from general inflammation of internal organs with eosinophilic granuloma formulation through ocular or brain involvement. There is also an asymptomatic form. The known factors that influence the clinical form of the disease are the intensity of the infestation, the localization of the larvae, the age of the patient, the efficiency of the immune system and the history of reinfection. The aim of our study was to evaluate the production of interleukins 4 (IL-4) and 10 (IL-10) in children in the course of Toxocara spp. infections with hepatic involvement. The analysis of peripheral leucocytes, eosinophils, immunoglobulin E, and IL-4 and IL-10 concentrations presented significantly higher values in children with radiologically confirmed liver granuloma than in uncomplicated hepatomegaly. Based on statistical analysis, we confirmed the IL-4/IL-10 ratio variation in the analysed groups: patients with liver lesions showed a ratio of <1, while children without granulomas had a ratio of >2. The relevant analysis confirmed a positive statistical correlation in both seropositive groups for IgE and IL-4, and only in the granuloma group for IgE and IL-10.

Human case of visceral larva migrans syndrome: pulmonary and hepatic involvement

Visceral Larva Migrans (VLM) syndrome is commonly caused by larvae of roundworms Toxocara canis or Toxocara cati. Human toxocarosis is a soil-transmitted zoonosis, which may result in partial or general pathological changes in host tissues. We reported a case of 14-year-old boy presented with severe dry cough without dyspnea, mild chest and abdominal pain with general fatigue. Examination of peripheral blood showed marked increase in eosinophils. The chest radiography showed an infiltrative shadow in the lung fields. Chest CT demonstrated multiple opacities in both lungs. Abdominal CT showed multiple low attenuation areas in the liver. Ultrasound guided liver biopsy revealed granulomas with severe eosinophilic infiltration. The boy was treated with albendazole and responded radically. It is worth mentioning that this is the first case of hepato-pulmonary VLM syndrome in Egypt.

Clinical characteristics and progression of liver abscess caused by toxocara

AIM: To evaluate the clinical characteristics and progression of liver abscess caused by toxocara.

METHODS: We retrospectively reviewed the medical records of patients with serum IgG antibody to Toxocara canis and liver abscess diagnosed using abdominal computed tomography between February 2010 and February 2015. Among 84 patients exhibiting serum IgG antibody to Toxocara canis, 34 patients were diagnosed with liver asbscess and treated with albendazole. A follow-up period of 1 year was conducted.

RESULTS: Mean patient age was 53 (34-79) years, with 26 (76.5%) patients being male. Twenty-one (61.7%) patients were moderate or heavy drinkers, 23 (67.6%) patients had a history of eating raw meat or liver and 6 (17.6%) patients owned pet dogs or cats. Main patient symptoms consisted of right upper quadrant pain, fever, and fatigue; 18 (52.9%) patients, however, presented with no symptoms. Lung involvement was detected in 444 (11.7%) patients. The eosinophil count increased in 29 (85.3%) patients at initial diagnosis, and decreased in most patients after albendazole treatment. The initial serum IgE level increased in 25 (73.5%) patients, but exhibited various response levels after albendazole treatment. Liver abscess formation improved in all patients.

CONCLUSION: The liver abscess was improved with albendazole treatment.

Evaluation of the Goldmann-Witmer coefficient in the immunological diagnosis of ocular toxocariasis

Ocular toxocariasis (OT) is a zoonotic parasitic infection mainly caused by the intraocular tissue invasion of second-stage Toxocara canis or Toxocara cati larva. Measuring specific anti-T. canis antibodies in the intraocular fluid (IF) can increase OT diagnosis accuracy using Goldmann-Witmer coefficient (GWC). However, there is no systemic evaluation of GWC application in the immunological diagnosis of OT. To assess GWC for the immunodiagnosis of ocular toxocariasis, paired IF and serum samples from 72 patients diagnosed with OT were retrospectively analyzed for specific anti-T. canis IgG by enzyme linked immunosorbent assay (ELISA). GWC values were calculated to determine intraocular specific IgG production. Clinical features and other laboratory data were recorded, and their correlations with GWC evaluated. Of the 72 OT patients, 60 (83.33%) showed intraocular specific IgG production confirmed by GWC, while intraocular nonspecific IgE production was found in 64/69 (92.75%) cases. No significant correlation was found among clinical features and IF specific IgG production. Values for peripheral blood samples were lower than those of intraocular fluid regarding OT screening, and vitreous humor samples showed increased local specific IgG and nonspecific IgE production compared with aqueous humor samples. Overall, our results indicate that GWC and intraocular IgE production have referential values in diagnosing ocular toxocariasis.

Update on Baylisascariasis, a Highly Pathogenic Zoonotic Infection

Baylisascaris procyonis, the raccoon roundworm, infects a wide range of vertebrate animals, including humans, in which it causes a particularly severe type of larva migrans. It is an important cause of severe neurologic disease (neural larva migrans [NLM]) but also causes ocular disease (OLM; diffuse unilateral subacute neuroretinitis [DUSN]), visceral larva migrans (VLM), and covert/asymptomatic infections. B. procyonis is common and widespread in raccoons, and there is increasing recognition of human disease, making a clinical consideration of baylisascariasis important. This review provides an update for this disease, especially its clinical relevance and diagnosis, and summarizes the clinical cases of human NLM and VLM known to date. Most diagnosed patients have been young children less than 2 years of age, although the number of older patients diagnosed in recent years has been increasing. The recent development of recombinant antigen-based serodiagnostic assays has aided greatly in the early diagnosis of this infection. Patients recovering with fewer severe sequelae have been reported in recent years, reinforcing the current recommendation that early treatment with albendazole and corticosteroids should be initiated at the earliest suspicion of baylisascariasis. Considering the seriousness of this zoonotic infection, greater public and medical awareness is critical for the prevention and early treatment of human cases.

Neurotoxocariasis: a systematic literature review

PURPOSE

Toxocariasis is a widespread zoonosis, which may result in central nervous system injury.

METHODS

We conducted a systematic literature review in MEDLINE, SciELO, ScienceDirect and Google Scholar up to April 2015 using a combination of the following search terms: "neurotoxocariasis" or "neurotoxocarosis", "toxocariasis" or "toxocarosis" and "cerebral" or "neurologic".

RESULTS

One hundred cases of neurotoxocariasis were identified in literature. The majority of patients were male (58 %), with a median age of 42 years. The predominant clinical pictures were myelitis (60 %), encephalitis (47 %) and/or meningitis (29 %). Fever was inconstant (23 %). The suspected mode of transmission, mentioned in only 49 % of cases, was mainly contact with dogs and/or cats (67 %) and ingestion of contaminated food (31 %). Diagnostic imaging examinations found hypodense lesions in cerebral scanner sequences and hyperintense lesions in cerebral MRI T2-weighted sequences in 65 and 57 % of encephalitis cases respectively, and in 92 % of myelitis cases in medullary MRI T2-weighted sequences. The detection of antibodies against Toxocara spp. was almost constant in blood and cerebrospinal fluid (CSF), 99 and 93 %, respectively. The two most commonly used drugs were corticosteroids (72 %) and/or albendazole (68 %) for a period of at least 3 weeks, which often needed to be repeated. Despite a low mortality rate (6 %), complete remission was observed in only 40 % of cases.

CONCLUSIONS

Neurotoxocariasis, a completely preventable zoonosis, could lead to severe sequelae failing prompt diagnosis. A compatible clinical picture, presence of risk factors, blood eosinophilia and high titers of antibodies against Toxocara spp. in CSF should alert physicians.

Production and evaluation of the recombinant antigen TES-30 of Toxocara canis for the immunodiagnosis of toxocariasis

INTRODUCTION

Toxocara canis is a pathogenic nematode of canines which can be accidentally transmitted to humans. Although serology is the most important diagnostic tool for this zoonosis, diagnostic kits use crude excretion/secretion antigens, most of them being glycoproteins which are not species-specific and may cross-react with antibodies generated against other parasites. 

OBJECTIVES

To produce the rTES-30 recombinant antigen of Toxocara canis and evaluate it in the immunodiagnosis of toxocariasis. 

MATERIALS AND METHODS

The gene that codes for TES-30 was cloned in the expression vector pET28a (+) using single-stranded oligonucleotides united by PCR. The protein rTES-30 was purified by Ni2+ affinity chromotography. Seroreactivity of rTES-30 was evaluated by immunoblot. Given that there is no gold standard test, the behaviour of the antigen was compared with the method that is routinely used to immunodiagnose toxocariasis, i.e., the conventional ELISA technique using excretion/secretion antigens. 

RESULTS

The rTES-30 was produced from an Escherichia coli LB culture which yielded 2.25 mg/L of the antigen with a purity of 95%. The results obtained showed 73% (46/63) concordance of reactivity between the rTES-30 immunoblot and the conventional ELISA, and 100% concordance with the nonreactive sera (21). Nineteen of the 21 sera positive for other parasitoses reacted with ELISA, while only seven of these were positive with the rTES-30 immunoblot. Concordance between the ELISA and the immunoblot was moderate (kappa coefficient: 0.575; 95% CI: 0.41- 0.74). 

CONCLUSIONS

The data presented show the potential of the rTES-30 inmunoblot for confirmation of possible ELISA positives, not only in epidemiological studies, but also as a candidate for the development of diagnostic tests for ocular toxocariasis in Colombia.

Latent and Asymptomatic Toxocara Infection among Young Population in Northwest Iran: The Necessity of Informing People as a Potential Health Risk

Objectives. This study was designed to determine the frequency of anti-Toxocara antibodies in youngsters aging from 2 to 20 years in northwest Iran. Materials and Methods. 397 samples were taken randomly almost equally from four locations in Urmia, west Azerbaijan, during August 2014 to September 2015. Anti-Toxocara IgG antibody assays were done on sera by using ELISA kit (IBL, Germany). In order to prevent cross-reaction, the samples of the patients who are infected with other parasites in stool exam, especially Ascarididae family, were also excluded. SPSS 16.0 software was used for statistical analysis. Results. 12 (3%) of the serum samples were positive for anti-Toxocara IgG. According to the Chi-square analysis, risk factors such as mother's educational level, keeping dogs or cats as pets, and history of coughing were related to Toxocara infection (P < 0.05). There was no relationship between toxocariasis and gender, history of onychophagy, pica, fever, abdominal pain, and anorexia; however, we found a significant relationship between Toxocara infection and chronic coughing (P = 0.045). Conclusion. Toxocariasis in northwest Iran can be considered as a public health problem. This study may also help to increase the awareness about this infection.

Clinical Characteristics of Pediatric Patients with Ocular Toxocariasis in China

Objective: The aim of the study was to analyze the clinical characteristics of pediatric patients with ocular toxocariasis. Methods: Ocular toxocariasis was diagnosed and treated in 46 children from Shanghai and surrounding provinces. The diagnosis of ocular toxocariasis was confirmed immunologically by performing an enzyme-linked immunosorbent assay on serum and/or intraocular fluid. All pediatric patients and their guardians completed a questionnaire concerning their cases and living habits. Results: The mean age of onset was 6 ± 3 years. Most children (85%) resided in rural areas, and 91% of the children had contact with adult dogs or puppies. At the first visit, visual acuity (VA) was <20/200 in 36 cases, and we detected peripheral granuloma in 36 patients. In our study, the most common signs were vitritis, vitreous strands, and tractional retinal detachment. The Optomap 200Tx device detected granuloma with an 85% sensitivity, which is much higher than that of other techniques. We treated 40 cases (87%) with topical corticosteroids, while 28 patients (61%) were treated with systemic corticosteroids. Only 18 children (39%) required surgical intervention. All patients were examined and treated by the same ophthalmologists. Conclusions: Preschool children in China are more often affected by toxocariasis compared with other age groups. The most common signs included unilateral granuloma and ocular inflammation. In our study, clinical manifestations were severe and complicated. At the first visit, VA was <20/200 in most patients. Ocular toxocariasis was diagnosed on the basis of clinical signs and symptoms; the diagnosis was confirmed by immunological testing. Techniques using the Optomap 200Tx device can facilitate the early detection and lead to better visual prognosis.

Cerebral Toxocariasis: Silent Progression to Neurodegenerative Disorders?

Toxocara canis and T. cati are highly prevalent nematode infections of the intestines of dogs and cats. In paratenic hosts, larvae do not mature in the intestine but instead migrate through the somatic tissues and organs of the body. The presence of these migrating larvae can contribute to pathology. Toxocara larvae can invade the brains of humans, and while case descriptions of cerebral toxocariasis are historically rare, improved diagnosis and greater awareness have contributed to increased detection. Despite this, cerebral or neurological toxocariasis (NT) remains a poorly understood phenomenon. Furthermore, our understanding of cognitive deficits due to toxocariasis in human populations remains particularly deficient. Recent data describe an enhanced expression of biomarkers associated with brain injury, such as GFAP, AβPP, transforming growth factor β1 (TGF-β1), NF-L, S100B, tTG, and p-tau, in mice receiving even low doses of Toxocara ova. Finally, this review outlines a hypothesis to explore the relationship between the presence of T. canis larvae in the brain and the progression of Alzheimer's disease (AD) due to enhanced AD-associated neurodegenerative biomarker expression.

Major Parasitic Zoonoses Associated with Dogs and Cats in Europe

Some of the most important zoonotic infectious diseases are associated with parasites transmitted from companion animals to man. This review describes the main parasitic zoonoses in Europe related to dogs and cats, with particular emphasis on their current epidemiology. Toxoplasmosis, leishmaniosis, giardiosis, echinococcosis, dirofilariosis and toxocariosis are described from the animal, as well as from the human host perspectives, with an emphasis on parasite life cycle, transmission, pathogenicity, prevention and identification of knowledge gaps. In addition, priorities for research and intervention in order to decrease the risks and burden of these diseases are presented. Preventing zoonotic parasitic infections requires an integrated multidisciplinary 'One Health' approach involving collaboration between veterinary and medical scientists, policy makers and public health officials.

Risk of soil-transmitted helminth infections on agritourism farms in central and eastern Poland

Agritourism provides ecological tourist services for urban dwellers in rural areas. Agritourism farms offer space and attractive scenery for people seeking to rest in quiet place and wanting healthy, outdoor recreational activities. The high epidemiological standard of agritourism farms is beneficial for the health of the farm owners and the guests. Upgraded level of the farm sanitation, also from parasitological point of view is of great importance, especially that among agritourism farms guests predominate families with small children. A field survey was carried out in 57 farms in central-eastern Poland to evaluate the environmental risk factors for geohelminth infections on agritourism farms offering tourist services for urban dwellers. Samples of soil were collected from 76 sites, i.e. yards surrounding houses, vegetable, fruit and flower gardens, playgrounds and sandpits. In addition, samples were taken from 27 public places of recreation (playgrounds at forest clearing) visited by agritourism farm guests. During visits the farms were inspected and the owners were questioned about their awareness of the threat of parasitic infections. Soil contamination with geohelminth eggs was found in 4 examined farms (7.0%), in one locality on each farm. The eggs of Toxocara spp. and Ascaris spp. were detected in single samples from 3 backyards (6.4%) and one sandpit (10.0%). In the soil samples from places of recreation outside the farms eggs of human or animal helminths were not identified. The results of this study showed that the risk of helminth infections on agritourism farms is low, since geohelminth eggs (1-3 per sample) were detected only in four samples (0.5%) among 760 collected from farms households. The farm owners must be aware of the importance of preventive measures to eliminate the environmental contamination with eggs of zoonotic soiltransmitted helminths. Special attention should be paid to the risk of intestinal parasites of cats of semi domestic behaviour migrating from neighbouring yards as well as of red foxes frequently observed in the vicinity of agritourism farms.

Kinetics and avidity of anti-Toxocara antibodies (IgG) in rabbits experimentally infected with Toxocara canis

An evaluation was made of the kinetics and avidity of anti-Toxocara antibodies (IgG) in rabbits experimentally infected with embryonated Toxocara canis eggs. Seventeen four month old New Zealand White rabbits were distributed into two groups. In the experimental group, twelve rabbits were infected orally with 1,000 embryonated T. canis eggs. A second group (n = 5), uninfected, was used as a control. Serum samples were collected for analysis on days 7, 14, 21, 28 and 60 post-infection (DPI). An indirect ELISA test was performed to evaluate the reactivity index (RI) of IgG anti-T. canis antibodies and to calculate the avidity index (AI). The animals showed seroconversion from the 14th DPI, with high AI (over 50%) except for one animal, which presented an intermediate AI. At 60 DPI, all the animals were seropositive and maintained a high AI. The data indicated that specific IgG antibodies formed early (14 DPI) in rabbits infected with T. canis, with a high avidity index that persisted throughout the course of the infection.

Lack of Association between Toxocara Exposure and Suicide Attempts in Psychiatric Patients

Infection with Toxocara may affect the central nervous system. A high seroprevalence of Toxocara infection has been reported in psychiatric patients. To the best of our knowledge, there is no previous report about an association of Toxocara infection with suicide attempts. Therefore, we sought to determine whether Toxocara exposure is associated with suicide attempts in psychiatric patients. We studied 282 psychiatric outpatients (156 with suicide attempts and 126 without suicide attempts). Sera of patients were analyzed for the presence of anti-Toxocara IgG antibodies by using a commercially available enzyme immunoassay. One of the 156 (0.6%) suicide attempters and 1 (0.8%) of the 126 controls were positive for anti-Toxocara IgG antibodies (OR = 0.80; 95% CI: 0.04–13.02; P = 1.00). Toxocara seropositivity was significantly higher (P = 0.01) in male patients with consumption of raw dried goat meat than male patients without this consumption. Results suggest that Toxocara exposure is not associated with suicide attempts in psychiatric outpatients in Durango City, Mexico. However, further studies with larger samples sizes to confirm our results should be conducted. Too few patients were seropositive to assess further associations of Toxocara exposure with sociodemographic, clinical, and behavioral characteristics of the psychiatric patients.

Study of Toxocara seroprevalence among patients with allergy and healthy individuals in Bulgaria

Data in the literature addressing the ability of Toxocara infection in humans to induce development of atopic disease are controversial. The aim of our study was to determine the seroprevalence of anti-Toxocara antibodies in three groups of people: subjects with allergic symptoms and presence of allergen-specific IgE, subjects with allergic symptoms and absence of allergen-specific IgE, and clinically healthy blood donors. Serum samples from all subjects were tested by ELISA and Western blot for presence of specific antibodies against Toxocara canis. The results of our study did not support the link between toxocariasis and allergic manifestations in atopic patients. Among subjects with allergic symptoms and absence of atopy was found seroprevalence of 2·2% in Western blot. Same index in patients with atopy was 0·8%, and in clinically healthy blood donors 4·0%. Our study gives us grounds to consider that it is appropriate persons with allergic reactions, without evidence of atopy to be tested for presence of anti-Toxocara antibodies in the course of their diagnostic evaluation. Data from clinically healthy persons suggest that there is a 'hidden' infection among the population, which is not clinically manifested.

Detection of IgG against Toxocara in Sera of Employees of Meat Industry

Contact with raw meat could represent a risk for Toxocara infection. We assessed the association of Toxocara infection with an occupation of meat worker though a case-control seroprevalence study of 124 meat workers and 248 subjects without this occupation. Sera of participants was analyzed for the presence of anti-Toxocara IgG antibodies. One (0.8%) of the 124 meat workers, and 5 (2.0%) of the 248 controls were positive for anti-Toxocara IgG antibodies (OR=0.39; 95% CI: 0.04-3.41; P=0.66). The seropositive meat worker was a male aged 28 years old, without vision impairment. None of the work characteristics i.e. frequency of contact with raw meat, use of safety practices, history of splashes at face with blood or raw meat, and injuries with sharp material at work was associated with Toxocara exposure. Seroprevalence of Toxocara infection was significantly higher (P=0.04) in meat workers with consumption of boar meat (1/6: 16.7%) than in those without this consumption (0/117: 0%). We conclude that meat workers do not have a higher risk for Toxocara infection than subjects without this occupation do. The 2% seroprevalence of Toxocara infection found in control subjects might suggest a low seroprevalence of this infection among people with other occupations in Durango City. However, additional case-control studies with larger sample sizes to confirm our results are needed.

Field evaluation of a rapid diagnostic test to detect antibodies in human toxocariasis

Human toxocariasis which is caused mainly by the larvae of Toxocara canis and Toxocara cati, is a worldwide zoonotic disease that can be a potentially serious human infection. The enzyme-linked immunosorbent assay (ELISA) using T. canis excretory-secretory (TES) antigens harvested from T. canis larvae is currently the serological test for confirming toxocariasis. An alternative to producing large amounts of Toxocara TES and improved diagnosis for toxocariasis is through the development of highly specific recombinant antigens such as the T. canis second stage larva excretory-secretory 30 kDa protein (recTES-30). The aim of this study was to evaluate the sensitivity and specificity of a rapid diagnostic kit (RDT, named as iToxocara kit) in comparison to recTES-30 ELISA in Serendah Orang Asli village in Selangor, Malaysia. A total of 133 subjects were included in the study. The overall prevalence rates by ELISA and RDT were 29.3% and 33.1%, respectively, with more positive cases detected in males than females. However, no association was found between toxocariasis and gender or age. The percentage sensitivity, specificity, positive predictive value and negative predictive value of RDT were 85.7%, 90.1%, 80% and 93.2%, respectively. The prevalence for toxocariasis in this population using both ELISA and RDT was 27.1% (36/133) and the K-concordance test suggested good agreement of the two tests with a Cohen's kappa of 0.722, P<0.01. In addition, the followed-up Spearman rank correlation showed a moderately high correlation at R=0.704 and P<0.01. In conclusion, the RDT kit was faster and easier to use than an ELISA and is useful for the laboratory diagnosis of hospitalized cases of toxocariasis.

Research on Toxocara canis antibodies obtained from patients with eosinophilia

BACKGROUND

Eosinophils may suggest the presence of a great variety of anomalies whereupon allergies, malignancies, certain tissue disorders, idiopathic hypereosynophilic syndrome and parasitic infections (with the exception of protozoons) can be cited as a few. Although the clinical manifestations may differ, the eosinophils level is quite an important data in cases related to the helminth infections. Similarly, in parasitic infections related to larva migrans (visceral, cutaneous, ocular), the eosinophils level is again a primary indicator and its evident cause is the roundworm Toxocara spp.

AIM

The aim of this study was to evaluate the significance characteristics of Toxocara spp. in patients with eosonophilia.

MATERIALS AND METHODS

In our study, serums were collected from 93 patients of various age groups with eosonophilia (10% and above) while visiting Istanbul University Medical Faculty due to various complaints.

RESULTS

Serum samples were treated with Toxocara IgG ready ELISA kit and Toxocara western blot IgG ready kit. Based on the ELISA method; out of 93 patients, 30 patients (32.3%) were positive. Western blot technique; 45 (48.4%) were positive with anti-toxocara IgG antibodies.

CONCLUSION

Results point out to western blot technique being more sensitive and superior on a scale of (P < 0.0001) when compared with the ELISA method.

Molecular cloning and characterization of arginine kinase gene of Toxocara canis

Toxocara canis is an important gastrointestinal nematode of dogs and also a causative agent of visceral larva migrans in humans. Arginine kinase (AK) gene is one of the important biomolecule of phosphagen kinase of T. canis which is emerging as an exciting novel diagnostic target in toxocarosis. The present study was carried out to clone and characterize AK gene of T. canis for future utilization as a diagnostic molecule. Total RNA was extracted from intact adult worms and reverse transcription was done with oligo dT primers to obtain complementary DNA (cDNA). Polymerase chain reaction (PCR) was carried out using cDNA as template with specific primers which amplified a product of 1,202 bp. The amplicon was cloned into pDrive cloning vector and clone was confirmed by colony PCR and restriction endonuclease analysis. Sequence analysis of the gene showed 99.8 and 77.9 % homology with the published AK gene of T. canis (EF015466.1) and Ascaris suum respectively. Structural analysis shown that the mature AK protein consist of 400 amino acids with a molecular wt of 45360.73 Da. Further expression studies are required for producing the recombinant protein for its evaluation in the diagnosis of T. canis infection in humans as well as in adult dogs.

The Prevalence of Toxocariasis and Diagnostic Value of Serologic Tests in Asymptomatic Korean Adults

Purpose

Toxocariasis is the most common cause of peripheral blood eosinophilia in Korea and produces eosinophilic infiltration in various organs, including the lung. However, the prevalence of toxocariasis in the general population is rarely reported.

Methods

We investigated the seroprevalence of Toxocara larval antibody among asymptomatic people who attended Samsung Medical Center for a health checkup, including low-dose chest computed tomography (CT) between March 2012 and December 2013. A total of 633 people (400 men and 233 women) were prospectively recruited.

Results

The Toxocara-seropositive rate was 51.2% using the current cutoff value based on Toxocara enzyme-linked immunosorbent assay (ELISA) (67.0% for men and 24.0% for women). In the multivariate-adjusted model, age (odds ratio [OR], 1.08; 95% confidence intervals [CI], 1.04-1.11), male sex (OR, 3.47; 95% CI, 2.26-5.33), rural residence (OR, 1.55; 95% CI, 1.05-2.30), and history of raw liver intake (OR, 8.52; 95% CI, 3.61-20.11) were significantly associated with Toxocara seropositivity. When subjects were divided into 3 groups using cutoff values base on weak positive and strong positive control optical densities (ODs), the ORs for peripheral blood eosinophilia and serum hyperIgEaemia were 0.31 (95% CI, 0.02-2.89) in the weakpositive group and 36.64 (95% CI, 11.73-111.42) in the strong positive group compared to the seronegative group. Similarly, ORs for the solid nodule with surrounding halo were 2.54 (95% CI, 0.60-10.84) in the weak positive group and 15.08 (95 CI 4.09-55.56) in the strong positive group compared to the seronegative group.

Conclusions

The study indicated that the Toxocara-seropositive rate obtained by using the current cutoff value based on ELISA was high in the asymptomatic population in Korea. The results of this study suggest that active toxocariasis may be more frequently seen in the Toxocara-strong positive group than in the Toxocara-weak positive group.

Seroprevalence, disease awareness, and risk factors for Toxocara canis infection among primary schoolchildren in Makoko, an urban slum community in Nigeria

In this study, we investigated the seroprevalence of Toxocara canis infection in southern Nigeria, which previously was unknown, in addition to evaluating disease awareness and potential risk factors for schoolchildren in an urban slum community. In total, 366 primary schoolchildren were investigated for the presence of anti-Toxocara IgG antibodies. Blood was collected and screened by a Western blot analysis based on the excretory-secretory antigens of larval T. canis (TcES), targeting low molecular weight bands of 24-35kDa specific for T. canis. Children were considered seropositive if their serum reacted with TcES when diluted to a titer of 1:32. Questionnaires concerning possible risk factors were given to the schoolchildren to acquire data on this infection. The overall seroprevalence of Toxocara infection was 86.1% (315/366). The logistic regression analysis of risk factors showed that children's age (odds ratio (OR)=2.88, 95% confidence interval (CI)=1.08-7.66, p=0.03), contact with dogs (OR=0.51, 95% CI=0.28-0.94, p=0.03), the age of the dog (OR=0.34, 95% CI=0.18-0.68, p=0.002), the feeding location of the dog (OR=0.31, 95% CI=0.12-0.79, p=0.01), the consumption of raw vegetables (OR=0.89, 95% CI=0.54-1.48, p=0.004), and the drinking of unboiled water (OR=0.48, 95% CI=0.26-0.90, p=0.02) were risk factors associated with Toxocara infection. Although there was a high awareness of dogs being hosts of some parasites in this study, not much was known about T. canis. This is the first serological investigation of T. canis infection among primary schoolchildren in southern Nigeria. The high seroprevalence recorded is an indication of high transmission with the consequent risk of visceral or ocular larval migrans and neurologic toxocariasis in these children. Our findings suggest the need for prompt interventional measures, particularly health education on personal hygiene.

Production of Toxocara cati TES-120 Recombinant Antigen and Comparison with its T. canis Homolog for Serodiagnosis of Toxocariasis

Toxocariasis is a cosmopolitan zoonotic disease caused by the infective larvae of Toxocara canis and T. cati. Diagnosis in humans is usually based on clinical symptoms and serology. Immunoglobulin G (IgG)-enzyme-linked immunosorbent assay kits using T. canis excretory-secretory (TES) larval antigens are commonly used for serodiagnosis. Differences in the antigens of the two Toxocara species may influence the diagnostic sensitivity of the test. In this study, T. cati recombinant TES-120 (rTES-120) was cloned, expressed, and compared with its T. canis homolog in an IgG4-western blot. The diagnostic sensitivity and specificity of T. cati rTES-120 were 70% (33/47) and 100% (39/39), respectively. T. canis rTES-120 showed 57.4% sensitivity and 94.4% specificity. When the results of assays using rTES-120 of both species were considered, the diagnostic sensitivity was 76%. This study shows that using antigens from both Toxocara species may improve the serodiagnosis of toxocariasis.

[Cardiovascular manifestations of human toxocariasis]

Toxocariasis is a parasitic infection produced by helminths that cannot reach their adult stage in humans. For their etiological species (Toxocara canis and Toxocara cati), man is a paratenic host. Infection by such helminths can produce a variety of clinical manifestations, such as: visceral larvae migrans syndrome, ocular larvae migrans syndrome and covert toxocariasis. In the visceral larvae migrans syndrome, the organs that are mainly involved include liver, lungs, skin, nervous system, muscles, kidneys and the heart. Regarding the latter, the importance of cardiovascular manifestations in toxocariasis, as well as its clinical relevance, has increasingly begun to be recognized. The current article is based on a systematic information search, focused mainly on the clinical and pathological aspects of cardiovascular manifestations in toxocariasis, including its pathophysiology, laboratory findings, diagnosis and therapeutical options, with the objective of highlighting its importance as a zoonosis and its relevance to the fields of cardiovascular medicine in adults and children.

Microarray gene expression analysis reveals major differences between Toxocara canis and Toxocara cati neurotoxocarosis and involvement of T. canis in lipid biosynthetic processes

Toxocara canis and Toxocara cati are globally occurring intestinal nematodes of dogs and cats with a high zoonotic potential. Migrating larvae in the CNS of paratenic hosts, including humans, may cause neurotoxocarosis resulting in a variety of neurological symptoms. Toxocara canis exhibits a stronger affinity to the CNS than T. cati, causing more severe neurological symptoms in the mouse model. Pathomechanisms of neurotoxocarosis as well as host responses towards the respective parasite are mostly unknown. Therefore, the aim of this study was to characterise the pathogenesis at a transcriptional level using whole genome microarray expression analysis and identify differences and similarities between T. canis- and T. cati-infected brains. Microarray analysis was conducted in cerebra and cerebella of infected C57Bl/6J mice 42daysp.i. revealing more differentially transcribed genes for T. canis- than T. cati-infected brains. In cerebra and cerebella of T. canis-infected mice, a total of 2304 and 1954 differentially transcribed genes, respectively, were identified whereas 113 and 760 differentially transcribed genes were determined in cerebra and cerebella of T. cati-infected mice. Functional annotation analysis revealed major differences in host responses in terms of significantly enriched biological modules. Up-regulated genes were mainly associated with the terms "immune and defence response", "sensory perception" as well as "behaviour/taxis" retrieved from the Gene Ontology database. These observations indicate a strong immune response in both infection groups with T. cati-infected brains revealing less severe reactions. Down-regulated genes in T. canis-infected cerebra and cerebella revealed a significant enrichment for the Gene Ontology term "lipid/cholesterol biosynthetic process". Cholesterol is a highly abundant and important component in the brain, representing several functions. Disturbances of synthesis as well as concentration changes may lead to dysfunction in signal transduction and neurodegenerative disease. Overall, only a minor overlap of differentially transcribed genes was observed between the two infection groups in both brain parts. Most genes are regulated individually in each infection group, supporting the evident differences of both roundworm species observed in the paratenic host in previous studies. In summary the present study underlines the differences in pathogenicity of T. canis and T. cati. It furthermore provides a comprehensive basis for future analyses over the course of infection as well as functional tests to identify gene regulatory circuits that are crucial for pathogenesis of neurotoxocarosis. The results of this study provide a promising foundation for further specific research to evaluate the particular pathogenetic mechanisms and to identify possible therapeutic targets.

Evaluation of Toxocara cati Excretory-Secretory Larval Antigens in Serodiagnosis of Human Toxocariasis

BACKGROUND

Toxocariasis is the clinical term that is applied to infection in the human host with Toxocara species larvae. Serological tests are important tools for the diagnosis of toxocariasis. The aim of this study was to evaluate the excretory-secretory (ES) antigens of T. cati larvae using enzyme-linked immunosorbent assay (ELISA) and also Western blotting for serodiagnosis of human toxocariasis.

METHOD

The ES antigens were prepared from T. cati third-stage larvae. Serum samples were obtained from 33 confirmed cases of toxocariasis, 35 patients infected with other parasitic diseases, and 30 from healthy individuals tested with ELISA and immunoblotting.

RESULTS

The ELISA showed appropriate performance in term of specificity (96.7%) and sensitivity (97.0%). Electrophoretic analysis of T. cati ES antigens revealed a range of 20- to 150-kDa fractions. The highest sensitivity was achieved with 42- and 50-kDa fractions.

CONCLUSION

The ELISA analyses using T. cati ES antigens demonstrated good sensitivity and specificity compared to T. canis ES as antigens for diagnosis of human toxocariasis. Accordingly, application of Western blotting, based on 42- and 50-kDa fractions of ES antigens, can be recommended for the accurate diagnosis of toxocariasis.

Visceral larva migrans syndrome: analysis of serum cytokine levels in children with hepatic lesions confirmed in radiological findings

Human toxocariasis is a helminth zoonosis resulting from accidental infection of humans by the roundworms Toxocara canis (T. canis) and cati (T. cati). The infection occurs in five forms: systemic (VLM), ocular, neurological, covert and asymptomatic. The aim of this study was to characterize the radiological and immunological findings in hepatic inflammation during the course of systemic infection by Toxocara sp. in children. Fifteen children, 2 to 17 years of age, with serological diagnosis of T. canis infection underwent abdominal ultrasonography and computer tomography (CT). Eosinophil counts, immunoglobulin E titres, interleukins IL-1α, IL-4, Il-6, IL-10 and interferon gamma were measured for all patients. Abdominal ultrasound revealed multiple hypoechoic areas in the livers of all patients. On the CT images, the hepatic lesions were seen as multiple, ill-defined, oval low-attenuating nodules that measured 6 to 9 millimetres in diameter. The nodules were usually best seen in the portal venous phase and were not seen on arterial-phase images. Significant intergroup differences were observed in the concentrations of IL-1α, IL-4, IL-6 and IL-10. The level of IFN-γ was not significantly elevated in patient sera relative to controls. The analysis shows that the production of anti-inflammatory cytokines is insufficient for granuloma formation in children presenting liver lesions in the course of VLM.

Frequency of Toxoplasma and Toxocara Sp. Antibodies in Epileptic Patients, in South Western Iran

OBJECTIVE

Epilepsy is a disorder of the brain characterized by an enduring predisposition to generate seizures. Infectious agents are mentioned in its etiology. With identifying and appropriate treatment of these infectious agents, preventing their secondary outcomes, including seizure is possible. This study was conducted to determine frequency of anti-Toxoplasma antibodies (IgG, IgM) and anti-Toxocara antibody (IgG) in epileptic patients.

MATERIALS & METHODS

Study sample consisted of 141 epileptic patients and 144 healthy people. After obtaining informed consents and completing demographic questionnaire, serum samples were taken from participants. The diagnostic test of Toxoplasma IgG & IgM and Toxocara antibodies was performed under the same conditions using ELISA method in a qualified private laboratory. Samples from patients and control groups with positive ELISA test in terms of anti-Toxocara antibody were also used for confirmatory Western blot test.

RESULT

According to ELISA results, 28 (19.85%) epileptic patients and 2(1.38%) of healthy people had anti-Toxocara antibodies (P<001), while 39 (30.46%) of the control group people and 14.18% of patients had anti-Toxoplsma antibodies (P=0.001).

CONCLUSION

Frequency of anti-Toxoplasma gondii is lower in epileptic than healthy individuals and this result is contrary to investigations that have reported higher levels of this antibody in such patient groups. ELISA results for Toxocara showed that the frequency of anti-Toxocara antibody in epileptic patients might empower the probability that this parasite may cause central nervous system damage. Western blotting has high specificity and is a proper confirmative method for diagnosis of toxocariasis.

Seroepidemiology of Toxocariasis in Children (5-15 yr Old) Referred to the Pediatric Clinic of Imam Hossein Hospital, Isfahan, Iran

BACKGROUND

Human toxocariasis, a helminthozoonosis, is due to the migration of Toxocara species larvae into human organisms. Humans, especially children become infected by ingesting of embryonated eggs from soil, dirty hands, and raw vegetables. Seroprevalence of this infection is high in developed countries, especially in rural areas. The aim of this study was to investigate the seroepidemiology of Toxocariasis in children referred to the pediatric clinic of Imam Hossein hospital, Isfahan, Iran.

METHODS

In this cross sectional study the sera of children aged 5 to 15 years old, admitted to Imam Hossein Pediatric Hospital were collected during 2013-14. Then the sera were examined for anti Toxocara canis antibodies using commercial ELISA kit.

RESULTS

From 427 children, 196 (45.9%) were female and 231(54.1%) were male. 107(25.1%) were from rural and 320 (74.9%) were from urban area. Of them 129 (30.2%) were contacted with dog. One child (0.2%) had hypereosinophilia, 33 (7.7%) eosinophlia, and 6 (1.39%) were positive for T. canis IgG (two male and four female). Four of infected children with T. canis were from urban (1.25%) and two from rural areas (1.9%). There was no significant correlation between education of parents, gender, age, place of living and contact with dog with ELISA results test.

CONCLUSION

Toxocariasis is prevalent in the children of Isfahan region. Results suggest a low Toxocara exposure in children in this area. Therefore, more risk factors associated with Toxocara exposure should be identified in the further investigation.

Seroepidemiology of Toxocara infection in patients with vision impairment and blindness in durango, Mexico

Background

Toxocara infection is a cause of vision impairment and blindness. We aimed to determine the seroprevalence and correlates of Toxocara infection in patients suffering from vision impairment and blindness in Durango City, Mexico.

Methods

Through a cross-sectional seroprevalence study, 204 patients with vision impairment and 19 blind patients were studied for the presence of anti-Toxocara IgG antibodies in Durango City, Mexico. Seroprevalence association with socio-demographic, housing, clinical, and behavioral characteristics of participants was also investigated.

Results

Five (2.5%) of the 204 patients with vision impairment, and none of the 19 patients with blindness were positive for anti-Toxocara IgG antibodies. In total, five of the 223 (2.2%) patients were positive for anti-Toxocara IgG antibodies. Seropositivity to Toxocara was not associated with age, sex, educational level, socio-economic status, presence of underlying diseases or behavioral characteristics of the patients. In contrast, multivariate analysis showed that Toxocara seropositivity was associated with living in a house with soil floor (odds ratio (OR) = 11.14; 95% confidence interval (CI): 1.57 - 78.74; P = 0.01).

Conclusions

This is the first report of Toxocara exposure in patients with vision impairment and blindness in Mexico, and of an association of Toxocara exposure with living in a house with soil floors. Results suggest a low Toxocara exposure in these patients in Durango, Mexico. The risk factor associated with Toxocara exposure identified in this study warrants for further investigation.

Low seroprevalence of Toxocara infection in schizophrenic inpatients in durango, Mexico: a case control study

Psychiatric patients have a higher seroprevalence of toxocariasis than general population. However, there is poor knowledge about any specific psychiatric diagnosis associated with toxocariasis. The aim of the study was to determine whether seropositivity to Toxocara was associated with schizophrenia. Through an age and gender-matched case-control seroprevalence study in Durango City, Mexico, 50 schizophrenic inpatients in a public psychiatric hospital and 100 control subjects of the general population were compared for the presence of anti-Toxocara IgG antibodies. One of the 50 (2%) schizophrenic inpatients, and 3 (3%) of the 100 controls were positive for anti-Toxocara IgG antibodies. No statistically significant difference in Toxocara seroprevalence among cases and controls was found (P=0.59). The Toxocara positive schizophrenic patient suffered from paranoid schizophrenia (F20.0) and had a number of putative risk factors for Toxocara exposure including contact with cats, dogs and other animals, worked in agriculture, and consumed undercooked meat, unwashed fruits and vegetables, and untreated water. Results suggest that seroprevalence of Toxocara infection was low and not associated with schizophrenia in psychiatric inpatients in Durango, Mexico. However, further studies to elucidate the association of toxocariasis with schizophrenia are needed.

Expect the unexpected: a case of isolated eosinophilic meningitis in toxocariasis

We present the case of a young police officer suffering from headache without other neurological symptoms caused by isolated eosinophilic meningitis, which resulted from an infection with Toxocara cati, along with a discussion of the differential diagnosis.

A case of ocular toxocariasis successfully treated with albendazole and triamcinolon

We present a case of ocular toxocariasis treated successfully with oral albendazole in combination with steroids. A 26-year-old male visited the authors' clinic with the chief complaint of flying flies in his right eye. The fundus photograph showed a whitish epiretinal scar, and the fluorescein angiography revealed a hypofluorescein lesion of the scar and late leakage at the margin. An elevated retinal surface and posterior acoustic shadowing of the scar were observed in the optical coherence tomography, and Toxocara IgG was positive. The patient was diagnosed with toxocariasis, and the condition was treated with albendazole (400 mg twice a day) for a month and oral triamcinolone (16 mg for 2 weeks, once a day, and then 8 mg for 1 week, once a day) from day 13 of the albendazole treatment. The lesions decreased after the treatment. Based on this study, oral albendazole combined with steroids can be a simple and effective regimen for treating ocular toxocariasis.