Pitfalls in Morphologic Diagnosis of Pathogens: Lessons Learned From the Pseudo- Cystoisospora Epidemic

Int J Surg Pathol. 2021 Apr;29(2):169-173. doi: 10.1177/1066896920960813. Epub 2020 Oct 5.

Abstract

Multiple groups have recently reported involvement of the gallbladder mucosa of immunocompetent patients by cystoisospora organisms. However, this has recently been disproved with the support of molecular and ultrastructural studies. Here we present a summary of these events, recounting how this pseudo-Cystoisospora epidemic began and ended. This review also highlights the important role played by ancillary techniques in supplementing the morphologic diagnosis of pathogens.

Keywords: Cystoisospora; epithelial; gallbladder; gastric; inclusion; molecular; ultrastructural.

Publication types

  • Review

MeSH terms

  • DNA, Protozoan / isolation & purification
  • Diagnostic Errors / prevention & control*
  • Epidemics
  • Gallbladder / parasitology
  • Gallbladder / pathology*
  • Gallbladder Diseases / diagnosis*
  • Gallbladder Diseases / epidemiology
  • Gallbladder Diseases / pathology
  • Genes, Protozoan / genetics
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Isospora / genetics
  • Isospora / isolation & purification
  • Isosporiasis / diagnosis*
  • Isosporiasis / epidemiology
  • Isosporiasis / pathology
  • Molecular Diagnostic Techniques / methods
  • Mucous Membrane / microbiology
  • Mucous Membrane / pathology
  • Polymerase Chain Reaction
  • RNA, Ribosomal, 18S / genetics

Substances

  • DNA, Protozoan
  • RNA, Ribosomal, 18S