Prevalence of Toxocara-induced liver granulomas, detected by immunohistochemistry, in a series of autopsies at a Children’s Reference Hospital in Vitoria, ES, Brazil

Abstract

The aim of this investigation was to study the frequency of visceral larva migrans (VLM) granulomas in autopsies at a Children's Reference Hospital in Vitoria, ES Brazil, where anti-Toxocara antibodies are frequently detected in the serum of children admitted at the hospital. Two liver fragments from 310 autopsies of children aged between 1 and 15 years were paraffin embedded, and sections were stained with hematoxylin and eosin and submitted to detection of Toxocara antigens using a rabbit anti-Toxocara serum. Among the 24 cases with granulomatous lesions, ten had eosinophil-rich granulomas positively stained with the anti-Toxocara serum. Some were typical epithelioid granulomas, with a positive reaction in multinucleated giant cells, epithelioid cells, or necrotic debris. The results showed that VLM granulomas are the most frequent granulomatous hepatitis in children in our county. This agrees with the high prevalence of anti-Toxocara antibodies in the serum of children admitted to the Children's Reference Hospital. The 3.2% frequency of liver VLM granulomas in autopsies is less than the 30-39% frequency of positive serology in these children, probably reflecting the low larval burden in infected children.

Cerebral Toxocariasis: Silent Progression to Neurodegenerative Disorders?

“…However, most pathology associated with VLM occurs in the liver. In Brazil, a study of 24 autopsy cases of granulomatous lesions in the livers of children from the Children's Reference Hospital found that eosinophilrich granulomas in 10 children (41.7%) stained positive with polyclonal anti-Toxocara serum (89). The pathological findings demonstrated that the hepatic granulomas possessed epithelioid cells and multinucleate giant cells forming a palisade around amorphous eosinophilic material or necrotic debris.…”

Solitary Hepatic Eosinophilic Granuloma Accompanied by Eosinophilia Without Parasitosis: Report of a Case

“…Sensitivities of ELISA and eosinophilia reportedly vary, although serum examination using ELISA offers the most important diagnostic clue. Some reports have documented high sensitivity and specificity of ELISA in adults and older children with EGL by VLM, 20,21 while others have described low sensitivity of ELISA. 22 On imaging, 23 EGL by VLM appears as a macroscopic nodule, rather than microscopic diffuse inflammation.…”

Immunodiagnosis of Human Toxocariasis

“…These methods should provide useful tools for the diagnosis and molecular epidemiological investigations of toxocariasis (Li et al 2007). Parasite antigens can be detected in granulomas by immunohistochemical techniques and are helpful for toxocariasis diagnosis (de Brito et al, 1994;Musso et al, 2007). Medical imaging techniques such as ultrasonography, computed tomography and magnetic resonance imaging have been used to detect granulomatous lesions due to the migration of Toxocara larvae in different locations such as liver, nervous system and eye (Degouy et al, 2001;Magnaval et al, 2001, Watthanakulpanich, 2010.…”