Toxocara Larva Research Articles

Recurrent vitreous opacity caused by intraocular Toxocara larva: a case report and literature review

BackgroundToxocara larva entity has seldom been reported on the surface of the retina. We report on an unusual case of recurrent vitreous opacity caused by intraocular Toxocara larva after vitrectomy.Case presentationA 34-year-old male was referred to our clinic with a 6-month history of decreased visual acuity in the right eye characterized as red, painless, and progressive. Optos fundus photograph showed optic disc elevation with granuloma, and proliferative membrane starting from the optic disc and running towards the superior temporal retina due to the movement of a Toxocara larva, which was covered by the proliferative membrane in the superior temporal retina. Since it adhered closely to the retina, the lesion in the superior temporal retina was not removed to avoid induction of an iatrogenic retinal break and the larva was not found during the first diagnostic pars plana vitrectomy. Intraocular Anti-Toxocara IgG was 45.53U (< 3, enzyme-linked immunosorbent assay (ELISA)), and the Goldmann-Witmer coefficient was 8.55, confirming the diagnosis of ocular toxocariasis. After this operation, visual acuity improved to 20/200. However, vitreous opacity worsened again, and the proliferative membrane expanded around the Toxocara larva three weeks after the operation. Toxocara larva was found and removed in the superior temporal region during the second operation. His visual acuity improved to 20/100, vitreous opacity disappeared, and the retina was stable two months after the second operation.ConclusionIt is advisable to remove suspected Toxocara larva to prevent the reoccurrence of ocular toxocariasis.

Image Case:Ocular Toxocariasis in 14 Years Old Male.

Toxocariasis is one of zoonotic infections all over the world that is caused by Toxocara canis and Toxocara cati. Infection with Toxocara occurs by accidentlal ingestion of embryonated eggs or larvae which have been shed in the feces of infected animals. After ingestion of the eggs, release of infective larvae in the small intestine occurs and then these penetrate the intestine then to the circulation, and then to different organs. Clinical presentation of toxocariasis in humans varies from asymptomatic infection to severe organ damage, which depends on the load of the parasite, the involved organs, and inflammatory response of the host. Particularly, depending on the involved organ, two clinical types can occur: systemic toxocariasis (which is known as visceral larva migrans) and ocular toxocariasis . The majority of the ocular toxocariasis cases are unilateral. To reach definitive diagnosis of ocular toxocariasis, biopsy of infected tissue should be obtained for histological demonstration of the Toxocara larva which is difficult in clinical practice. So, we depend on the presence of typical ophthalmologic signs and the presence of serum antibody to the Toxocara larvae for diagnosis of ocular toxocariasis. A 14 years old male presented by progressive decrease in visual acuity in the left eye with no history of trauma or medications, with blood picture showed no esinophilia. Slit lamp examination was normal. Coloured fundus photography and fluorescein angiography of the left eye revealed evidence of fibrous band stretching from the optic disc to a peripheral retinal mass located in the far peripheral nasal retina which is highly suggestive of ocular toxocariasis. Patient received medical treatment in the form of systemic corticosteroids ( 1mg/kg) and diethyl carbamazine ( 6 mg/kg per day) for one month then reexamination was done and coloured fundus photography of the eye revealed marked improvement of the traction bands on the macula with improvement of visual acuity .

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.

The role of Toxocara larva migransin hypereosinophilia with unknown origin in patients referred to laboratories

The role of Toxocara larva migransin hypereosinophilia with unknown origin in patients referred to laboratories Mahdi Mosayebi, Reza Hajihossein, Mojtaba Didehdar, Zahra Eslamirad, Mostafa Ejtehadifar, Zeinab Hamzelo Abstract Background: Toxocariasis is a parasitic infection in dogs and cats, and human gets infected with larva migrants when embryonated eggs are accidentally ingested. Migration of toxocara larvae to tissues causes inflammatory responses (visceral, ocular and cerebral) and eosinophilia increase in blood. This study was aimed to investigate the human toxocariasis, one of the possible causes of hypereosinophilia with an unknown origin. Methods: This case-control study was performed on 100 hypereosinophilic patients (cases) and 100 people with normal eosinophil count (controls) that referred to hematology department of laboratories of Arak University of Medical Sciences in 2012. Epidemiological data were collected by a questionnaire and diagnosis was performed using excreted-secreted antigens of Toxocara (TES Ag - ELISA). Results: Positive test for toxocariasis in hypereosinophilic patients was 16% and in patients with normal eosinophil count was zero (P=0.001). There was no statistically significant difference between groups in terms of gender, age, residential place, occupation and education level (P>0.05). However, there was a significantly higher history of contact with dogs and consumption of unclean fruits and vegetables in the infected patients (p<0.05). The mean of eosinophilia in patients with toxocariasis showed a significant difference compared with that of eosinophilia in patients not infected with toxocariasis (p=0.001). Conclusion: The results confirmed the role of toxocariasis in hypereosinophilic patients with unknown origin, and eosinophilia can be considered to analyze and treat toxocariasis. Keywords Toxocariasis, visceral larva migrans, hypereosinophilia

First Case of Toxocara Eosinophilic Ascites After Combined Pancreas and Kidney Transplantation

To the Editor: In August 2008, a 47-year-old man who had undergone combined pancreas and kidney transplantation 7 years before presented with massive ascites, deterioration of general health, temperatures up to 37.2°C (= 99°F) and nausea. Laboratory results showed no signs of infection or dysproteinemia nor hepatic or kidney injury. As a potential rejection was excluded by bioposies of the transplanted organs mild eosinophilia was assumed to be due to the patient's immunosuppressive regimen with tacrolimus, sirolimus and mycophenolate mofetil. Abdominal ultrasound revealed only ascites and gastroscopy showed mild gastritis. Abdominal computed tomography (CT) scan was unremarkable. The hepatic venous pressure gradient measured according to guidelines (1Groszmann R Vorobioff JD Gao H Measurement of portal pressure: When, how, and why to do it..Clin Liver Dis. 2006; 10 (499–451)Abstract Full Text Full Text PDF Scopus (33) Google Scholar) was in the normal range. All screenings for malignancies were negative. In the meanwhile the ascites had required aspiration. The hyper-proteinaemic fluid did not show any signs of infection, but as it contained rare eosinophils, a complete cardiovascular workup was ordered. Echocardiography and cardiac MRI were unremarkable. The ascites continued to resist treatment and required frequent paracentesis. The patient's general health nonetheless remained stable. The same symptoms and nonresponsive ascites had persisted for two months when massive numbers of eosinophilic cells appeared in the fluid and called for careful review by an infectiologist. When it developed that the patient and his dog had spent a two-week summer vacation in Croatia, serology for Toxocara twice produced a positive result. After two five-day cycles of albendazole 400 mg b.i.d., the ascites subsided. The patient is currently in good health with no signs of ascites. The ubiquitous Toxocara spp. (family Ascaridiae) are nematodes. They reside as Toxocaria canis in the small intestine of dogs and other canines and as Toxocaria cati in cats and other felines. A study has shown that 32.2% of dogs and 24.3% of cats in Germany are infected with these intestinal parasites, and 67% of stray dogs carry Toxocara eggs in their fur. The reproduction rate of one worm/d is 200,000 eggs, with 50,000 eggs in 1 g of stool. The eggs contaminate the soil down to 10 cm and remain infectious for 4 years (2Schantz PM Stehr-Green JK Toxocara larva migrans..J Am Vet Med Assoc. 1998; 192: 28-32Google Scholar). Humans are the final hosts for these nematodes. Fecal-oral transmission of Toxocaria eggs initiates the life cycle. Eggs hatch in the small bowel, then the larvae migrate out of the intestine, primarily to the liver, the lungs as visceral larva migrans and to the eye as ocular larva migrans (3Schantz PM Glickman LT Roundworms in dogs and cats: Veterinary and public health considerations..Comp Contin Vet Educ. 1981; 3: 773-784Google Scholar). The literature reports two cases of Toxocara associated eosinophilic ascites (4Chira O Badea R Dumitrascu D et al.Eosinophilic ascites in a patient with toxocara canis infection a case report..Rom J Gastroenterol. 2005; 14: 397-400PubMed Google Scholar) in children (5Cruz AT, Franklin GY, Kaplan SL. Toxocariasis causing eosinophilic ascites. Pediatr Infect Dis J 27: 563–564.Google Scholar) but none in an immunosuppressed patient. A serologic survey of the US population measured Toxocara seroprevalence at 2.8%. Most of these infections were asymptomatic. Immune deficiency need not rule out pet ownership but potential pets should be tested for Toxocara—as pets can be considered an enormous psychological benefit to people with chronic diseases (6Angulo FJ Glaser CA Juranek DD Caring for pets in immunocompromised persons..J Am Vet Med Assoc. 1994; 205: 1711-1718PubMed Google Scholar). The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation.

Transvitreal migration of a Toxocara larva resulting in a second chorioretinal granuloma

Transvitreal migration of a Toxocara larva resulting in a second chorioretinal granuloma

33-Year-Old Woman With Marked Eosinophilia

33-Year-Old Woman With Marked Eosinophilia

Persistent airway hyper‐responsiveness and inflammation in Toxocara canis‐infected BALB/c mice

Infection with Toxocara canis, the roundworm of dogs, has been associated with asthmatic manifestations. Clinical symptoms such as wheezing, coughing and episodic airflow obstruction have been described for patients infected with this helminth. In order to characterize the effect of T. canis infection on the lungs, we monitored immune responses, pulmonary pathology and lung function over a period of 60 days in BALB/c mice. Infection was performed by a single oral administration of 1000 T. canis embryonated eggs. Airway responsiveness was measured in conscious, unrestrained mice at 7, 14, 30 and 60 days post-infection (p.i.). Infection of mice resulted in airway hyper-responsiveness (AHR) that persisted up to 30 days p.i. Pulmonary inflammation as well as increased levels of IgE and eosinophils in bronchoalveolar lavage (BAL) persisted up to 60 days p.i. Cytokine analysis in BAL indicated increased levels of IL-5 at day 7 and 14 p.i., whereas the levels of IL-2, IFN-gamma, IL-4 and IL-10 did not differ from those of uninfected controls. Toxocara-specific stimulation of spleen cells using recombinant TES-70 protein resulted in the induction of IL-5 at day 7 and 14 p.i. and IL-10 at day 14 p.i. Production of all other cytokines did not differ from that of uninfected controls. Evaluation of larval burden revealed that T. canis was still present in the lungs of infected mice at 60 days p.i. The presence of Toxocara larva in the lungs at 60 days p.i. following a single infection could explain the persistent pulmonary inflammation, airway hyper-reactivity, eosinophilia and increased IgE production observed in T. canis-infected BALB/c mice.

Following the migration of a Toxocara larva in the retina by optical coherence tomography and fluorescein angiography

The Toxocara larva is known to migrate across the retina, but the layer in which it migrates and its effect on the retina has been unknown. An ocular Toxocara infection was diagnosed by an immunological test on a vitreous sample from a patient with a retinal lesion that had migrated. Optical coherence tomography (OCT) and fluorescein angiography (FA) were used in this investigation. Many small lesions were first detected in the peripheral retina, and vitrectomy was performed because of vitreous haze. Two peripapillary lesions were found during the vitrectomy. OCT of one lesion demonstrated a highly reflective mass located in the nerve fiber layer, and FA showed dye leakage from the lesion as well as hyperfluorescence of the disc. Three weeks later, another lesion was found in the macular area, and OCT and FA findings were the same as for the first lesions. Fluorescein leakage was also observed along the presumed path of the migrating larva. The movement of the lesion from the peripapillary area to the macular area suggested that a Toxocara larva had migrated across the retina. OCT images indicated that the larva moved in the nerve fiber layer, and FA showed that it caused severe inflammation along its pathway.

Post-streptococcal reactive myalgia: a novel syndrome secondary to infection with group A or G streptococci

it is a symptom of one of the inflammatory rheumatic Borrelia burgdorferi/Brucella spp./Coxiella multisystem diseases or whether it is caused by an burnetii/rickettsiae/Staphyloccus/b-haemolytic infectious disease. In this grand round, we will pay streptococci/Legionella pneumophila/Leptospira Parasites: [25‐28] special attention to infectious diseases as a cause of Toxoplasma/Isospora hominis/ myalgia. Pleistophora/Trypanosoma cruzi/ Spirometra spp./Onchocerca volvulus/ PATIENT 1 Trichinella spp./Schistosoma spp./ Toxocara larva migrans/Taenia solium A 39-yr-old female, who worked in a children’s Pyomyositis: [14‐17] residential unit, had a sore throat. About 5 days later, streptococci/Staphylococcus aureus she developed severe incapacitating myalgia in the Chlamydia [29] upper and lower arms, and legs. She was unable to do Mycoplasma pneumoniae [30] her work and had to stay at home for several weeks. Endocarditis [24] Multisystem disease: [32‐44] She had no other specific complaints and systems polymyositis/dermatomyositis/inclusion body

Diffuse Unilateral Subacute Neuroretinitis: Report of Transvitreal Surgical Removal of a Subretinal Nematode

The precise identification of nematodes which cause diffuse unilateral subacute neuroretinitis (DUSN) has been unsuccessful. Shape and size are useful in the initial stages of identification, but histopathologic examination usually is necessary for accurate classification. Intact nematodes recovered from patients with DUSN have been mentioned scarcely in the literature. The authors report the first case of DUSN in which a viable nematode was removed successfully via a transvitreal surgical approach and recovered for parasitologic study. Bimanual pars plana vitrectomy was performed in a 9-year-old Brazilian boy with typical DUSN in its late stage. During surgery, a motile subretinal nematode was confirmed temporal to the macular area. A retinotomy was created adjacent to the nematode. The subretinal material then was aspirated with a 20-gauge soft-tip needle, and parasitologic examination was performed. Based on length (630 m x 10(-6)) and width (30 m x 10(-6)) of the nematode and other features such as a small buccal capsule, an esophagus one third of body length, and tapered tail, a morphologic identification of the nematode was made as a third-stage Toxocara larva. Histopathologic examination could not be performed for confirmation because of subsequent deterioration of the specimen. Although direct laser photocoagulation of the nematode is the treatment of choice for DUSN, surgical transvitreal removal of the nematode may be indicated in selected cases. This method for treatment allows removal of the nematode for parasitologic identification.

Visceral Larva Migrans

To the Editor. —The clinicopathologic case report by Patrick R. O'Connor, MD, titled Visceral Larva Migrans of the Eye that appeared in the NovemberArchives(88:526, 1972) raises several important issues. The author concludes that his patient, who had the clinical characteristics of Coats disease (peripheral retinal telangiectasia and aneurysms with subretinal yellow exudate and serous retinal detachment), actually harbored a toxocara larva. Although this is an intriguing hypothesis, I do not think that the author provides satisfactory histologic evidence that there was a larval infestation. The photomicrograph (Fig 3) showing cholesterol clefts and adjacent chronic inflammatory change is certainly not pathognomonic for a larval granuloma. In fact, this picture looks more like organized hemorrhage or lipid exudate and is frequently seen in Coats disease. Before this case can be accepted as an example of ocular toxocara infection, stricter histological criteria must be met. One would have to demonstrate classic