Visceral larva migrans presenting as multiple intracranial and intraspinal abscesses

Involvement of nervous system by toxocariasis is rare and can produce a spectrum of pathology that includes eosinophillic meningoencephalitis, meningomyelitis, space occupying lesions, vasculitis causing seizures or behavioral abnormalities posing diagnostic dilemmas. We describe a 38-year-old man who presented with multiple intracranial and intramedullary abscesses caused by visceral larva migrans. Neurohelminthiasis as a cause of multiple abscesses, though rare, should be entertained as a differential diagnosis particularly in tropical South-east Asian countries where helminthiasis is still an epidemiological concern prevalent in the pediatric age group.

Toxocariasis in Japan

Toxocariasis has long been considered a parasitic disease affecting pet owners and children who often play in sandboxes at public parks. Recent cases of this animal-borne infection, however, indicate that its clinical manifestations and etiologies are changing. In this article, we will describe the critical characteristic features of toxocariasis alongside the contributions of Japanese researchers to a better understanding of the disease.

Parasitic pulmonary eosinophilia

Parasitic infections, although common in tropical and subtropical regions, are prevalent worldwide because of changing immigration patterns and in international travel. The burden of worm infection is enormous and the intensity of infection is usually high among the poor and in immunocompromised individuals. Pulmonary eosinophilia occurs in almost all metazoan infections. In the Western world, the most common infections are caused by Strongyloides, Ascaris, Toxocara, and Ancylostoma species. Most of the nematodes multiply within the human host and cause pulmonary eosinophilia during larval migration through the lungs. Despite larval migration through the lungs, there is usually no permanent lung damage. The result is an increased number of eosinophils in the airways or lung parenchyma with or without peripheral eosinophilia. Löffler's syndrome, visceral larva migrans, and tropical pulmonary eosinophilia are the most common infections that cause pulmonary eosinophilia. The most serious parasitic eosinophilic lung disease is tropical pulmonary eosinophilia, a disorder caused by the filarial worms Wuchereria bancrofti and Brugia malayi, in which cases have typically been reported to masquerade acute or refractory bronchial asthma. Increasing awareness, newer diagnostic techniques, preventative measures, and antiparasitic drugs are important in reducing the worldwide morbidity and mortality from parasitic helminths and protozoa. This review focuses on common and some uncommon causes of pulmonary parasitic eosinophilia and their manifestations, diagnosis, and management.

MRI studies of spinal visceral larva migrans syndrome

We report serial MR findings in four patients with myelitis caused by visceral larva migrans syndrome due to Toxocara canis or Ascaris suum infection. MR imaging revealed spinal cord swelling with or without gadolinium enhancement in three patients. T2-weighted images showed high signal intensities preferentially located in both lateral and posterior columns. Antihelmintic and corticosteroid treatment yielded improvement in neurologic deficits and spinal lesions. However, one patient with T. canis infection relapsed associated with reappearance of MRI abnormalities.

The cerebral form of toxocarosis in a seven-year-old patient

INTRODUCTION

Toxocarosis is a consequence of human infection by Toxocara canis larvae. There are symptomatic (visceral, ocular) and asymptomatic courses of toxocarosis. The cerebral form is very rare.

CASE REPORT

We present a seven-year-old patient who developed a cerebral form of toxocarosis. She demonstrated focal neurological symptoms (epilepsy) confirmed by neuro-imaging and histopathological examinations. A positive test for toxocarosis essentially completed the other outcomes. On the basis of the clinical picture and the conducted tests a diagnosis of a cerebral form of toxocarosis was established. Mebendazole was applied in treatment.

[Toxocariasis. A cosmopolitan parasitic zoonosis]

The infection by Toxocara canis transmitted by dogs (30% of them are infected in our countries) and less frequently by cats lead to larva migrans visceral syndrome with neurological manifestations, ophtalmological affection and various cutaneous manifestations observed in 24% of the extra-ocular infections: chronic urticaria often associated with asthmatic manifestations and chronic rhinitis, angio-oedema or local oedema reaching particularly the eyclid, chronic pruritus associated with lesions due to scratching or to nodular prurigo. An hypereosinophilia is an argument in favour of a progressive infection. High total IgE is an hallmark of visceral infections by parasites and total IgE level is well correlated with the presence of intra-tissular larva. The serological diagnosis is based on the determination of specific IgG by ELISA which appears also to be interesting for the patient's follow up. The western blot method seems to be more specific than the other methods and so is useful to confirm a diagnosis. The treatment given as early as possible is based on the use of diethylcarbamazine but also of thiabendazole, albendazole and mebendazole. Prophylaxis of toxocara infection includes the prohibition of dog access to children games areas but also a frequent turn over of the sand in public parks.

Visceral larva migrans mimicking rheumatic diseases

OBJECTIVE

To report rheumatologic or rheumatologic-like manifestations of the visceral larva migrans (VLM) syndrome.

METHODS

We carried out a prospective study of patients with VLM seen in a private practice setting in Mexico City between 1990 and 1993.

RESULTS

From a population of 600 patients we identified 6 patients (5 women) with VLM. Three patients complained of arthralgia; in 4 a history of migratory cutaneous lesions was elicited, and in one monoarthritis of the right knee was found. One patient had deep edema that suggested thrombophlebitis of the right arm; the man in our series had right testicular swelling during followup. In 2 cases, panniculitis was documented by biopsy and in one, small vessel vasculitis. Four patients had frequent contact with dogs and one with cats; 4 patients frequently ate raw fish. The diagnosis of VLM was confirmed either by the clinical picture, biopsy, or ELISA:

CONCLUSION

The spectrum of rheumatological manifestations in VLM may be wider than previously thought.

Clinical and laboratorial features of visceral toxocariasis in infancy

Forty children with a diagnosis of Visceral Toxocariasis were evaluated prospectively from February 1982 to June 1989. Diagnosis was established by clinical, laboratory and serological (ELISA - ES Toxocara canis antigen) evaluations. A great clinical polymorphism was found in our patients, ranging from unspecific or absent manifestations to an exuberant symptomatology. The laboratory findings were: leukocytosis, eosinophilia and elevation of serum gammaglobulin and isohemagglutinin levels. No significant relationship between clinical findings and laboratory parameters was found. Serology (ELISA) was a method of great diagnostic support but did not show a correlation with clinical and laboratory findings in this study. There was a significant relationship between pulmonary manifestations and the presence of signs and/or symptoms, when the patients were sent to us. Our findings, especially the high incidence of pulmonary manifestations, suggest that Visceral Toxocariasis has to be included in the differential diagnostic of children with pulmonary manifestations, characteristic epidemiological data and associated eosinophilia.

Experimental toxocariasis and hyperactivity in mice

An observational study using videorecordings and computer-assisted data analysis was undertaken in order to investigate the behaviour of mice infected with larvae of Toxocara canis. The findings indicated that the infection had a marked effect on five readily and reliably differentiable categories of murine behaviour. A marked increase in the number of shorter bouts of each of the five behaviours was also associated with the infection. These results support previous findings and further suggest that T. canis infection affects the way in which mice respond to their environment. In particular the infection appears to be associated with hyperactivity in mice. Possible causes of such behavioural abnormalities as well as implications of these findings for clinical studies concerned with relationships between T. canis infection and hyperactivity in children are discussed.