A worm in the toilet bowl! What does it tell us about the challenges in the identification of supposed human parasites in practical parasitology?

Authors

  • Hudson A. Pinto Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
  • João Rodrigo Campos Laboratório Lustosa, Belo Horizonte, Minas Gerais, Brazil
  • Larissa C. M. Gomes Laboratório Lustosa, Belo Horizonte, Minas Gerais, Brazil
  • Vinícius S. Costa Laboratório Lustosa, Belo Horizonte, Minas Gerais, Brazil
  • Hyllo B. Marcello Junior Laboratório Lustosa, Belo Horizonte, Minas Gerais, Brazil
  • Vitor Luís Tenório Mati Departamento de Medicina, Universidade Federal de Lavras, Lavras, Minas Gerais, Brazil

Keywords:

annelid, diagnosis, helminths, misidentification, pseudoparasitism, epistemology

Abstract

Non-parasitic vermiform organisms can circumstantially be associated with humans and their identification can be challenging for medical professionals. The present report describes the finding of a worm in the toilet bowl by a patient from Brazil, who thought he had expelled it in his feces. The gross analyses in a clinical laboratory reveal the worm was different from other macroscopic organisms routinely identified, and the laboratory staff requested assistance in an academic laboratory specialized in helminthology. After preliminary analysis in a stereomicroscope, the supposed human worm was identified as an oligochaete annelid (earthworm). The patient was contacted to investigate a possible case of pseudoparasitism. However, we were informed that the organism had been collected in a toilet bowl from a rural environment where the untreated water comes from a cistern indicating our finding was circumstantial. The methodology revisited herein allowed a quick microscopic analysis of easy-to-view morphological structures, which are useful to separate oligochaete annelids from helminths and can prevent misdiagnosis in similar situations. We discuss the overly restricted view on human parasites by health professionals in collecting clinical history and laboratory analysis, providing some epistemological insights on the necessary interdisciplinarity between parasitology and other basic knowledge with health practice.

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Published

2023-09-25

How to Cite

Pinto, H. A., Campos, J. R., Gomes, L. C. M., Costa, V. S., Marcello Junior, H. B., & Tenório Mati, V. L. (2023). A worm in the toilet bowl! What does it tell us about the challenges in the identification of supposed human parasites in practical parasitology?. Annals of Parasitology, 69(1), 31–36. Retrieved from https://annals-parasitology.eu/index.php/AoP/article/view/21

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Section

Case reports