Abstract: Objective  To diagnose 10 cases of clinically suspected cases of sparganosis mansoni by pathogen identification.  Methods  In the period from August 2009 to August 2011, 10 biopsy specimens were obtained from 10 patients of four hospitals to identify the pathogen. Among the 10 cases, 4 cases showed abdominal subcutaneous mass, 3 showed eyelid swelling, 1 displayed brain lesions, 1 showed pulmonary mass, and 1 showed pleural effusion. There was one parasite each from three patients with eyelid swelling, and one patient with abdominal subcutaneous mass, which were observed by naked eye and microscope morphologically and histologically. Specimens from other six cases were examined by microscope after paraffin embedding, sectioning, and HE staining. For further identification, the parasite biopsy tissue specimens were detected by immunohistochemistry with Sparganum mansoni-immunized rabbit serum as the primary antibody.  Results  Three intact worms, from three patients with eyelid swelling, showed typical S. mansoni morphological characteristics. One residue parasite from the abdominal subcutaneous mass showed network structures and full of calcareous corpuscles in the body under microscope same as that of S. mansoni. The histological structure in three of the six sections showed typically the body wall with folds, which was dense, thick and deeply eosine stained, part of the tegument outside was covered by micro-hairs. In the worm body there was net-like loose structure and calcareous corpuscles without cavity. The structure of the other three worm sections was atypical. The six worm sections were positive by immunohistochemical detection.  Conclusion  The 10 clinically suspected cases are diagnosed as sparganosis mansoni.

Key words: Sparganosis mansoni, Pathogen identification, Parasite histology, Immunohistochemistry