[Atypical ocular toxocariasis in a child: A case report]. / Toxocarose oculaire atypique chez un enfant : à propos d'un cas.

INTRODUCTION: Ocular toxocariasis is a rare disease, predominantly affecting children and young adolescents, and usually presenting as unilateral posterior uveitis. We report the case of a child with toxocariasis associated with serous retinal detachment. OBSERVATION: A 8-year-old child with no previous history of toxocariasis was referred for a 1-year decline in visual acuity, unimproved by optical correction, with vitreous condensation on examination, without central or peripheral granulomas, and serous retinal detachment on OCT. The diagnosis was made after extensive questioning, with evidence of contact with dogs and positive serology. Medical treatment combining corticosteroid therapy and antiparasitic therapy was initiated, and the clinical picture improved. DISCUSSION: Ocular toxocariasis is a rare infection, unilateral in 90% of cases. Its clinical manifestation in children is pars planitis, posterior uveitis with a posterior pole chorioretinal focus associated with vitreoretinal traction and/or peripheral granuloma. In our case, the patient presented with vitreous condensation only, with OCT serous retinal detachment and no peripheral or central granulomas. Positive plasma serology or ocular samples confirmed the diagnosis. CONCLUSION: Ocular toxocariasis should not be ruled out in the absence of a typical clinical picture, and seropositivity enables confirmation of the diagnosis when clinical suspicion arises.

Case Report: Toxocariasis Manifesting as Eosinophilic Pleural Effusion.

Toxocariasis is a prevalent zoonosis caused by infection with the larvae of Toxocara canis or Toxocara cati. It ranges in severity from mundane to life-threatening, depending on organ involvement. The lungs are often affected, manifesting as coughing, wheezing, and chest pain. However, pleural effusions rarely occur in patients with pulmonary toxocariasis. We report the case of a 74-year-old man with highly suspected toxocariasis who presented with an eosinophilic pleural effusion and eosinophilia. He developed dyspnea and a right-sided pleural effusion. Thoracentesis revealed an exudative effusion containing numerous eosinophils. The pleural effusion continued to increase, and the eosinophilia rapidly progressed. Although the patient had not recently had contact with animals or known exposure to contaminated food, water, or soil, toxocariasis was confirmed by positive serological test results for anti-Toxocara antibodies in the serum and pleural effusion. The patient was cured with albendazole treatment for 28 days. The pleural effusion and eosinophilia resolved and did not recur. Clinicians should consider toxocariasis in the differential diagnosis of patients presenting with eosinophilic pleural effusions.

Cerebro-Ocular Toxocariasis Revealed by Bilateral Cystoid Macular Edema.

DESIGN: Case Report Case description: This report describes the case of a female patient diagnosed with oculo-cerebral toxocariasis manifesting initially in the form of isolated bilateral cystoid macular edema. Diagnosis was made by means of positive anterior chamber and lumbar puncture western blots. The unusual presentation, ancillary findings and treatment are discussed. The control of intraocular inflammation that was only partially responsive to steroids was eventually achieved with pegylated interferon alfa-2a. CONCLUSION: Isolated macular edema is a rare presentation of ocular toxocariasis. Interferon alfa-2a may prove useful in case of insufficient control of inflammation.

Fatal visceral larva migrans from Toxocara catis infection of the heart and liver in a child.

We discuss the pathophysiology and epidemiology of Toxocara catis infection complicated by visceral larval migrans . We describe a previously healthy 19-month-old white male child found dead in bed by his mother. He had what was thought to be an upper respiratory infection for several days.The child had eosinophilic hepatitis and myocarditis complicating visceral larval migrans due to Toxocara catis infection from the family cat. We discuss the pathologic and clinical aspects of visceral larval migrans due to of Toxocara catis infection.

A case report of spinal toxocariasis with extensive tumor-like involvement.

BACKGROUND: Toxocariasis is a common parasitic infection worldwide. Although it can present as several clinical syndromes, neurological manifestation is rare. Only a few reports are available on spinal cord involvement of toxocariasis. We report a case that presented with gait disturbance due to progressive lower limb spasticity. The patient had had visceral toxocariasis infection 8 years before. A spine magnetic resonance image (MRI) showed syringomyelia along the entire thoracic cord with small nodular enhancing lesions in the mid-portion of the syrinx, which led to the suspicion of ependymoma. Surgical mass removal was performed. However, histopathological examination of the mass did not show any malignant cells; instead, there were numerous axonal retraction balls with an eosinophilic granular body-like appearance. The serum antibody titer against toxocariasis was borderline high. Taken together, these observations led to a diagnosis of Toxocara infection, and the patient was treated with albendazole. CONCLUSION: To the best of our knowledge, this is the first case report of tumor-like spinal toxocariasis involving extensive lesions. A solid enhancing mass with accompanied syrinx and hemorrhage might be a Toxocara infection. It can easily be diagnosed with serologic tests and simply be treated with oral albendazole if suspected.

Exposure to Toxocara Canis is not Associated with New-Onset Epilepsy.

Purpose: The association between exposure to Toxocara canis and epilepsy is at the best contentious. Most of previous studies were retrospective, community-based, and contradictory to one another. As the impact of a positive association on the magnitude of epilepsy will be huge especially in developing countries where toxocariasis is common owing to poor hygienic practices, this study was carried out to determine whether exposure to T. canis predisposes to development of epilepsy. Patients and Methods: This case-controlled observational study was carried out a tertiary healthcare center in North India on 120 patients with newly diagnosed epilepsy who presented within 3 months of diagnosis. A total of 120 age- and sex-matched individuals from the same community were chosen as controls. Epilepsy was defined according to ILAE 1993 definition. Serological testing for T. canis was carried out using commercially available ELISA kits. All the positive samples were subjected to Western blot testing for confirmation. Results: The prevalence of antibodies to T. canis was similar in cases (16/120; 13.3%) and controls (16/120; 13.3%). Among the various risk factors, history of pica was significantly associated with T. canis seropositivity, while lack of hand washing was significantly associated with higher risk of epilepsy. Conclusion: Our study could not find any association between exposure to T. canis and epilepsy.

Toxocara canis infection worsens the course of experimental autoimmune encephalomyelitis in mice.

Toxocara canis, a gastrointestinal parasite of canids, is also highly prevalent in many paratenic hosts, such as mice and humans. As with many other helminths, the infection is associated with immunomodulatory effects, which could affect other inflammatory conditions including autoimmune and allergic diseases. Here, we investigated the effect of T. canis infection on the course of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. Mice infected with 2 doses of 100 T. canis L3 larvae 5 weeks prior to EAE induction (the Tc+EAE group) showed higher EAE clinical scores and greater weight loss compared to the non-infected group with induced EAE (the EAE group). Elevated concentrations of all measured serum cytokines (IL-1α, IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ and TNF-α) were observed in the Tc+EAE group compared to the EAE group. In the CNS, the similar number of regulatory T cells (Tregs; CD4+FoxP3+Helios+) but their decreased proportion from total CD4+ cells was found in the Tc+EAE group compared to the EAE group. This could indicate that the group Tc+EAE harboured significantly more CD4+ T cells of non-Treg phenotype within the affected CNS. Altogether, our results demonstrate that infection of mice with T. canis worsens the course of subsequently induced EAE. Further studies are, therefore, urgently needed to reveal the underlying pathological mechanisms and to investigate possible risks for the human population, in which exposure to T. canis is frequent.

Association between toxocariasis seropositivity and serointensity and cognitive function in older U.S. adults.

The nematodes Toxocara canis (Werner, 1782) and Toxocara cati (Schrank, 1788) have been associated with worse human cognitive function in children and middle-aged adults. In this study, we sought to determine the association between Toxocara seropositivity and serointensity determined by detection of IgG antibodies against the Toxocara antigen recombinant Tc-CTL-1 and cognitive function in older adults, including approximately 1,350 observations from the 2013-2014 National Health and Nutrition Examination Survey. Mean fluorescence intensity was used to quantify IgG antibodies against the Toxocara recombinant Tc-CTL-1 antigen, and respondents were considered positive at values greater than 23.1. In adjusted models from sample sizes ranging from 1,274 to 1,288 depending on the individual cognitive task, we found that Toxocara seropositivity was associated with worse performance on the animal-fluency task (b = -1.245, 95% CI: -2.392 to -0.099, P< 0.05) and the digit-symbol coding task (b = -5.159, 95% CI: -8.337 to -1.980, P< 0.001). Toxocara serointensity assessed using log-transformed mean fluorescence intensity as a continuous variable was associated with worse performance on the digit-symbol coding task (b = -1.880, 95% CI: -2.976 to -0.783, P < 0.001). There were no significant associations with tasks assessing memory. Further, age modified the association between Toxocara and cognitive function, although sex, educational attainment, and income did not. These findings suggest that Toxocara might be associated with deficits in executive function and processing speed in older U.S. adults, although additional research is required to better describe cognitive function in older adults who are seropositive for Toxocara spp.

A Case Report of Intravitreal Dexamethasone Implant with Exudative Retinal Detachment for Ocular Toxocariasis Treatment.

Toxocariasis is one of the most common geohelminth infections in several parts of the world. We describe a rare case of ocular toxocariasis with secondary exudative retinal detachment treated with albendazole and an intravitreal dexamethasone implant. A 13-year-old boy with counting finger vision was diagnosed with retinal vasculitis and exudative retinal detachment in his right eye. Fundoscopic examination revealed retinal hemorrhage, retinal vasculitis, and exudative retinal detachment. Serological test using serum and intraocular aqueous humor were positive for anti-Toxocara specific IgG antibodies. He received repeated doses of intravitreal dexamethasone implants combined with oral albendazole. A sequential follow-up optical coherence tomography revealed that the retina was successfully reattached. His visual acuity subsequently improved to 20/400.

A rare case of toxocariasis presenting with hypereosinophilic pericardial effusion and mycotic aneurysm.

Parasitic infections are the leading cause of hypereosinophilia in the paediatric population in tropical countries. We report an unusual case of Toxocara infection in an eight-year-old boy who presented with intermittent fever, hypereosinophilia complicated by massive pericardial effusion and a mycotic aneurysm. This child received treatment with four weeks of albendazole and steroids.

Toxocariasis-Associated Acute Perimyocarditis with Cardiogenic Shock: A Case Report.

BACKGROUND Toxocariasis is an infection due to ingestion of the helminth parasite larvae found in dogs (Toxocara canis) or cats (Toxocara cati). Symptoms vary from being asymptomatic to shock, depending on the organ invaded by the parasite. However, cardiac involvement with shock in toxocariasis is very rare. CASE REPORT A 21-year-old woman without any history of underlying conditions visited the Emergency Department because of epigastric pain, vomiting, headache, and dizziness. Her blood pressure was 80/60 mmHg. Computed tomography (CT) of the brain showed no abnormal lesions. The abdominal-pelvic CT with contrast showed right pleural effusion, pericardial effusion, and focal ascites in the pelvic cavity. Laboratory tests revealed an elevation of eosinophils (40%) and cardiac enzymes (creatinine kinase-MB 27.6 ng/mL, high-sensitive cardiac troponin T 1.21 ng/mL). The transthoracic echocardiogram showed left ventricular systolic dysfunction (ejection fraction 44%) and moderate pericardial effusion. She was presumptively diagnosed with hypereosinophilic perimyocarditis and admitted to the Intensive Care Unit for shock. The pericardial effusion increased during treatment; therefore, pericardiocentesis was performed. Analysis of the pericardial effusion showed eosinophilia (eosinophils 90%) and the serologic test for parasites was positive for Toxocara and Sparganum. A combination therapy of albendazole, praziquantel, and corticosteroid resolved the pericardial effusion and the peripheral blood eosinophil count normalized. She was discharged without any other complications. At Outpatient Clinic follow-ups and observations over the next 2 years there were no abnormal findings, including pericardial effusion or eosinophilia. CONCLUSIONS Toxocariasis rarely causes perimyocarditis with cardiogenic shock. Patients who present with pericardial effusion and eosinophilia need to be evaluated for parasitic infection.

Cerebral Toxocariasis as a Cause of Epilepsy: A Pediatric Case.

Toxocarosis is the consequence of human infection by Toxocara spp. larvae and is one of the most common ascarioses, not only in developing countries, but also in the European region, where its prevalence reaches 14%. Due to their particular behavior, children are at higher risk of this parasitic infection, whose clinical features depend on the localization of the Toxocara larvae. Neurotoxocariasis is very uncommon in children and may take different forms depending on the underlying physiopathologic process: immune reaction against the parasite antigens, vasculitis, treatment complications, or, very rarely, brain localization of Toxocara spp. larvae. The association between neurotoxocariasis and the onset of childhood epilepsy has been postulated but is still debated. Moreover, a Toxocara spp. abscess causing epileptic seizures in children has been rarely described, especially in western countries. Hereby we present a 9-year-old patient with a new diagnosis of epilepsy definitely secondary to brain abscess due to the localization of Toxocara canis larvae. Diagnosis was confirmed by neuroimaging and serological test. The successful treatment with albendazole and steroids was documented with a close and long-term clinical and neuroradiological follow-up. Our experience confirms that every case of cryptogenetic epilepsy in children deserves a neuroimaging study and, in case of cystic images, Toxocara serology is mandatory to avoid further unnecessary invasive diagnostic investigations and to set the specific drug therapy.

Toxocariasis Presenting with Hypereosinophilia and Lymphadenopathy: A Case Report.

Human toxocariasis is a parasitic disease transmitted to humans by ingestion of Toxocara spp. larvae. Rural area residents and children have higher risk for this parasitic infection. The disease is frequently asymptomatic; however, it may cause symptoms such as cough, fever, headache, myalgia or other conditions such as lymphadenopathy and granulomatous hepatitis. Albendazole is used for the treatment of toxocariasis diagnosed by serologic and immunological methods. Herein, we report two cases of toxocariasis that were investigated due to hypereosinophilia and lymphadenopathy for a long time.

Prevalence of Toxocariasis and Its Risk Factors in Patients with Eosinophilia in Korea.

Eosinophilia occurs commonly in many diseases including allergic diseases and helminthic infections. Toxocariasis has been suggested as one cause of eosinophilia. The present study was undertaken to examine the prevalence of toxocariasis in patients with eosinophilia and to identify the risk factors for toxocariasis. This prospective cohort study recruited a total of 81 patients with eosinophilia (34 males and 47 females) who visited the outpatient clinic at Seoul National University Hospital from January 2017 to February 2018 and agreed to participate in this study. The prevalence of toxocariasis was examined by T. canis-specific ELISA, and the various risk factors for toxocariasis were evaluated by a questionnaire survey. Among 81 patients with eosinophilia, 18 were positive for anti-T. canis antibodies (22.2%); 88.9% were male (16/18) and 11.1% were female (2/18). Multivariate statistical analysis revealed that males (OR 21.876, 95% CI: 1.667-287.144) with a history of consuming the raw meat or livers of animals (OR 5.899, 95% CI: 1.004-34.669) and a heavy alcohol-drinking habit (OR 8.767, 95% CI: 1.018-75.497) were at higher risk of toxocariasis in patients with eosinophilia. Toxocariasis should be considered a potential cause of eosinophilia when the patient has a history of eating the raw meat or livers of animals in Korea. A single course of albendazole is recommended to reduce the migration of Toxocara larvae in serologically positive cases with eosinophilia.

Evidence for Asthma in the Lungs of Mice Inoculated with Different Doses of Toxocara canis.

Toxocara canis, a common roundworm that mainly causes toxocariasis, is a zoonotic parasite found worldwide. Humans, an accidental host, can acquire T. canis infection through accidental ingestion of T. canis-embryonated egg-contaminated food, water, and soil, and by encapsulated larvae in a paratenic host's viscera or meat. Long-term residence of T. canis larvae in a paratenic host's lungs may induce pulmonary inflammation that contributes to lung injury, airway inflammatory hyperresponsiveness, and collagen deposition in mice and clinical patients. This study intended to investigate the relationship between T. canis infection and allergic asthma in BALB/c mice inoculated with high, moderate, and low doses of T. canis eggs for a 13-week investigation. The airway hyperresponsiveness (AHR) to methacholine, collagen deposition, cytokine levels, and pathological changes in lung tissues was assessed in infected mice at weeks 1, 5, and 13 postinfection. The cell composition in bronchoalveolar lavage fluid of infected mice was assessed at weeks 5 and 13 postinfection. Compared with uninfected control mice, all groups of T. canis-infected mice exhibited significant AHR, a dose-dependent increase in eosinophilic infiltration leading to multifocal interstitial and alveolar inflammation with abundant mucus secretion, and collagen deposition in which the lesion size increased with the infective dose. Infected mice groups also showed significant expressions of eotaxin and type 2 T-helper-dominant cytokines such as interleukin (IL)-4, IL-5, and IL-13. Overall, these results suggest that T. canis larval invasion of the lungs may potentially cause pulmonary inflammatory injury and could subsequently contribute to the development of allergic manifestations such as asthma.

Neurocognitive and neuropsychiatric effects of toxocariasis.

Caused by the neuroinvasive nematodes Toxocara canis and Toxocara cati, human toxocariasis has a worldwide distribution with seroprevalence in humans associated with low socioeconomic status and low educational attainment. Third-stage Toxocara larvae can invade human tissues, including the brain and spine, where they can result in encephalitis, meningitis, and inflammation. Toxocara infection in animal models has been associated with cognitive and behavioural changes. In humans, preliminary cross-sectional research suggests that Toxocara seropositivity is associated with worse cognitive function in children and adults. Additional preliminary cross-sectional findings suggest associations between Toxocara seropositivity and neuropsychiatric function, including schizophrenia and neurologic conditions such as epilepsy. Given the widespread distribution of human toxocariasis and early evidence suggesting that it can be associated with cognitive and neuropsychiatric function in humans, additional research regarding the effects of toxocariasis on the human brain is required.