New animal model for human ocular toxocariasis: ophthalmoscopic observation.
BACKGROUND/AIMS: Although human ocular toxocariasis causes severe vision defect, little is known about its aetiology, diagnosis, and treatment. To develop a new animal model for human ocular toxocariasis, ophthalmological findings of fundi in Mongolian gerbils, Meriones unguiculatus, and BALB/c mice were investigated following infection with Toxocara canis. METHODS: Using an ophthalmoscope, which was specifically developed to observe the fundi of small animals, ocular changes of fundi of 20 gerbils and 11 mice were monitored after oral infection with embryonated eggs of T canis. RESULTS: Vitreous, choroidal, and retinal haemorrhages were consistently observed in Mongolian gerbils, but rarely in mice. Severe exudative lesions and vasculitis were often present in gerbils but not in mice. Migrating larvae were also frequently observed in gerbils. CONCLUSION: Mongolian gerbils are more appropriate animal model for human ocular toxocariasis than previously used experimental animal such as mice, guinea pigs, rabbits, and monkeys because of its high susceptibility of ocular infection. (+info)
Case studies in international travelers.
Family physicians should be alert for unusual diseases in patients who are returning from foreign travel. Malaria is a potentially fatal disease that can be acquired by travelers to certain areas of the world, primarily developing nations. Transmitted through the bite of the Anopheles mosquito, malaria usually presents with fever and a vague systemic illness. The disease is diagnosed by demonstration of Plasmodium organisms on a specially prepared blood film. Travelers can also acquire amebic infections, which may cause dysentery or, in some instances, liver abscess. Amebiasis is diagnosed by finding Entamoeba histolytica cysts or trophozoites in the stool. Invasive amebic infections are generally treated with metronidazole followed by iodoquinol or paromomycin. Cutaneous larva migrans is acquired by skin contact with hookworm larvae in the soil. The infection is characterized by the development of itchy papules followed by serpiginous or linear streaks. Cutaneous larva migrans is treated with invermectin or albendazole. Case studies are presented. (+info)
Intestinal parasites of raccoons (Procyon lotor) from southwest British Columbia.
This is the first extensive survey of metazoan parasites (particularly of the roundworm Baylisascaris procyonis) from the intestines of raccoons in British Columbia. The sample collected in 1997-1998 consisted of 82 raccoons that had been sick or had been killed accidentally by automobiles. Fifteen parasite taxa were found: 3 nematodes, 9 digenetic trematodes, 2 acanthocephalans and 1 cestode. Ten of these parasites constitute new host records for raccoons, including 4 digenetic trematodes that have been reported in marine birds and mammals on the Pacific Coast of North America. Baylisascaris procyonis infected 61% of the raccoons with a mean intensity of 27. The high rate of infection indicates a large potential for environmental contamination and, thus, human and animal exposure to infectious eggs. Prevention of larva migrans is discussed, particularly for people in contact with raccoons in wildlife rehabilitation centers. (+info)
Treatment of cutaneous larva migrans.
Cutaneous larva migrans caused by the larvae of animal hookworms is the most frequent skin disease among travelers returning from tropical countries. Complications (impetigo and allergic reactions), together with the intense pruritus and the significant duration of the disease, make treatment mandatory. Freezing the leading edge of the skin track rarely works. Topical treatment of the affected area with 10%-15% thiabendazole solution or ointment has limited value for multiple lesions and hookworm folliculitis, and requires applications 3 times a day for at least 15 days. Oral thiabendazole is poorly effective when given as a single dose (cure rate, 68%-84%) and is less well tolerated than either albendazole or ivermectin. Treatment with a single 400-mg oral dose of albendazole gives cure rates of 46%-100%; a single 12-mg oral dose of ivermectin gives cure rates of 81%-100%. (+info)
Outbreak of cutaneous larva migrans in a group of travellers.
We describe an outbreak of cutaneous larva migrans (CLM) in a group of 140 holidaymakers to a resort in Barbados and the index case. methods A two-page questionnaire was mailed to holidaymakers and 90% responded. results 25.4% of respondents developed a rash consistent with CLM. Risk factors for developing the illness were younger age and less frequent use of protective footwear while walking to the beach. Patients had difficulty in obtaining a correct diagnosis during their initial medical consultation and in obtaining medication from pharmacies. Efficacious treatments were oral and topical thiabendazole. conclusions CLM can occur in a large proportion of people exposed to contaminated soil or sand. Protective footwear is effective in reducing infection. Thiabendazole is an efficacious treatment. (+info)
Cutaneous larva migrans in travelers: a prospective study, with assessment of therapy with ivermectin.
The purpose of this prospective study was to update epidemiological data on cutaneous larva migrans (CLM) and to assess the therapeutic efficacy of ivermectin. We performed the study between June 1994 and December 1998 at our travel clinic. Ivermectin (a single dose of 200 microg/kg) was offered to all the patients with CLM, and its efficacy and tolerability were assessed by a questionnaire. Sixty-four patients were enrolled. All were European and had stayed in tropical areas. After the patients had returned from their destinations, 55% had lesions occur within a mean of 16 days (range, 1-120 days; >1 month in 7 patients). The initial diagnosis was wrong in 55% of patients. The mean number of lesions was 3 (range, 1-15), and the main sites were the feet (48%) and buttocks (23%). The cure rate after a single dose of ivermectin was 77%. In 14 patients, 1 or 2 supplementary doses were necessary, and the overall cure rate was 97%. The median time required for pruritus and lesions to disappear was 3 and 7 days, respectively. No systemic adverse effects were reported. Physicians' knowledge of CLM, which can have a long incubation period, is poor. Single-dose ivermectin therapy appears to be effective and well tolerated, even if several treatments are sometimes necessary. (+info)
Five cases of ocular toxocariasis confirmed by serology.
We report 5 cases of ocular toxocariasis in Korean adults complaining of visual impairment along with floating or bubbling sensation. Fundoscopic examination revealed a retinal detachment along with exudate in 4 cases. They all showed typical reaction by ELISA and immunoblot against Toxocra excretory-secretory antigen. One case showed high level of anti-Toxocara IgE antibodies (34,000 Toxocara units/L) as well as increased level of serum total IgE antibodies and the specific IgE antibodies for 3 inhalant antigens, suggesting that high level of anti-Toxocara IgE antibodies was associated with an atopic status. Clinical manifestations were improved after the sequential use of steroids then mebendazole. We also suggest that ocular toxocariasis should be thoroughly investigated even when an evocative uniocular inflammatory lesion is encountered in peripheral retina without a systematic disease. (+info)
Two imported cases of cutaneous larva migrans.
Cutaneous larva migrans (CLM) is a rare serpiginous cutaneous eruption caused by accidental penetration and migration in the skin with infective larvae of nematode that normally do not have the human as their host. Although CLM has a worldwide distribution, the infection is most frequent in warmer climates. More recently, they have been increasingly imported from the tropics or subtropics by travelers. We experienced two patients who had pruritic serpiginous linear eruption in their skin for a few weeks after traveling to the endemic areas (Brazil and Thailand, respectively). After the treatment with albendazole, the skin lesions resolved with post-inflammatory hyperpigmentation. We report herein two cases of cutaneous larva migrans successfully treated with albendazole. (+info)