Angiostrongylus costaricensis egg antigen for the immunodiagnosis of abdominal angiostrongyliasis.

Angiostrongylus costaricensis is the aetiological agent of human abdominal angiostrongyliasis, a parasitic disease reported from the United States to Argentina, with a widespread occurrence of the nematode throughout Central and South America. This study assesses the performance of A. costaricensis eggs as antigen in an enzyme-linked immunosorbent assay (ELISA), for the determination of parasite-specific IgG1 antibodies. The specificity and the sensitivity of the method were 87% and 90.5%, respectively. Through this test it was possible to demonstrate a sharp and early decline in IgG1 antibody in serum samples taken from patients with histopathological diagnosis of abdominal angiostrongyliasis at different time points after surgical treatment. The present work demonstrated the usefulness of the egg antigen in the development of a specific diagnostic test for abdominal angiostrongylosis.

First reported outbreak of abdominal angiostrongyliasis.

Human abdominal angiostrongyliasis is a potentially fatal disease caused by Angiostrongylus costaricensis, a nematode found in the Americas. During the period of December 1994 through August 1995, an outbreak of this disease occurred in Guatemala. We identified 22 cases of abdominal angiostrongyliasis and conducted a matched case-control study to identify risk factors for illness. The median age of the 18 cases enrolled in the study was 37 years (range, 9-68 years), and 11 (61.1%) were male. Consumption of the following six raw food items was associated with angiostrongyliasis: mint (odds ratio [OR], 6.9; 95% confidence interval [CI], 1.5-66.0), shrimp (OR, infinite; 95% CI, 1.4 to infinite), and four kinds of ceviche that reportedly contained raw mint (OR for consumption of mint or ceviche that contained mint, 7.0; 95% CI, 1.0-315). We conclude that raw mint was the likely vehicle of infection for this outbreak. To our knowledge, this is the first reported outbreak of abdominal angiostrongyliasis and the first time that a specific food item has been epidemiologically linked to the disease.

Angiostrongylus costaricensis natural infection in Vaginulus plebeius in Nicaragua.

A study of 94 slugs, collected from urban and rural areas in and around Léon, Nicaragua, was carried out in order to confirm the role of Vaginulus plebeius as an intermediate host of Angiostronglylus costaricensis. Third-stage larvae of A. costaricensis were obtained from these molluscs. Some of these larvae were then orally inoculated into two laboratory-bred rats Sigmodon hispidus and adult worms of A. costaricensis were recovered two months later. The infection rate of these slugs ranged from 4% in urban areas to 85% in rural areas. These data suggest that contamination to man is a major risk especially in rural areas and that abdominal angiostrongyliasis could be a health problem in Nicaragua.

Abdominal angiostrongyliasis in Nicaragua: a clinico-pathological study on a series of 12 cases reports.

A retrospective study was done to determine the presence of abdominal angiostrongyliasis in Nicaragua. Twelve cases of this parasitic disease were found among 48 visceral specimens: small intestine, liver and testes. The patients with intestinal lesions presented symptoms of an acute abdomen, and in some instances, a tumor-like mass was palpated in the lower right quadrant. A thickening of the intestinal wall accompanied by necrosis and perforation were the most important macroscopic findings. One patient with hepatic localisation of Angiostrongylus costaricencis displayed a clinical picture of visceral larva migrans-like syndrome. The chief laboratory findings were leukocytosis and eosinophilia. The histopathological examination showed granulomas and heavy eosinophilic infiltration around the eggs and larvae of A. costaricencis. Also, an adult worm was seen in one biopsy.

[Influence of the age of Veronicellid slugs in Angiostrongylus costaricensis infection]. / Influencia de la edad de los veronicélidos en la infección con Angiostrongylus costaricensis.

In Costa Rica, Veronicellid slugs are the most important intermediate hosts for Angiostrongylus costaricensis. Apparently, these molluscs develop a resistant mechanism after being exposed to the infection. In naturally infected slugs, the higher infection rates were found in large slugs, but they usually bear few larvae. Large number of larvae were found in medium sized molluscs. Experimental infection in laboratory breed slugs produced an amebocytic reaction around developing larvae; later, the formation of a fibrotic capsule is observed. When there is a second infection, cell reaction is stronger and the larvae show degenerative signs. This cell-mediated resistant mechanism seems to explain why the biggest molluscs, although more probably exposed to infection, bear fewer larvae.

First record of Angiostrongylus costaricensis Morera and Céspedes, 1971 in Ecuador.

Third-stage metastrongyle larvae were recovered from slugs (Vaginulus sp.) collected in Santa Lucia, Ecuador, a town about 40 miles north of Guayaquil. Some of the larvae were inoculated into laboratory-bred cotton rats and adults of Angiostrongylus costaricensis were later recovered. This is the first report of this parasite in Ecuador.

First record of angiostrongylus cantonensis in Cuba.

The occurrence of human eosinophilic meningoencephalitis in several localities of Havana, Cuba, prompted a search for the rat lungworm, Angiostrongylus cantonensis, in the same localities. Twenty rats (Rattus norvegicus) and about 370 terrestrial mollusks (70 slugs, Veronicella cubensis, and about 300 snails, mostly Bradybaena similaris) were collected in six communities of the Province of Havana, and in the gardens of the Pedro Kouri Institute for Tropical Medicine in Havana City. Adult lungworms were found in 12 of the rats and larvae were recovered from a large number of pooled lots of the mollusks. Observations on the morphology and life history of the parasites confirmed the presence of A. cantonensis in the American region.

[Infection of wild rats with Angiostrongylus costaricensis by intraperitoneal subcutaneous route]. / Infección de ratas salvajes con Angiostrongylus costaricensis por vía subcutánea e intraperitoneal.

Three groups of cotton rats (Sigmodon hispidus) were infected with Angiostrongylus costaricensis; the first was inoculated by stomach tube; the second intraperitoneally and the third subcutaneously. In all the groups each rat received 50 L3. The highest rates of infection (51.5%) were obtained by the intraperitoneal route, followed by oral inoculation (47.1%). Poor results were observed (10.5%) subcutaneously.