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Unusual Case of Pseudomembranous Colitis Presenting as Fever of Unknown Origin Diagnosed by Tc-99m-HMPAO-labeled Leukocytes SPECT/CT


  • Rosanna Del Carmen Zambrano-Infantino
  • Jean Félix Piñerúa-Gonsálvez
  • Noelia Alvarez-Mena
  • Sandra Izquierdo-Santervás
  • Noelia Alcaide
  • Maria Garcia-Aragon
  • Ricardo Ruano-Pérez

Received Date: 29.08.2022 Accepted Date: 25.12.2022 Mol Imaging Radionucl Ther 2023;32(2):168-170 PMID: 37337874

The fever of unknown origin (FUO) represents a complex diagnostic challenge due to the wide range of etiologies that could cause it, including neoplastic, infectious, rheumatic/inflammatory, and miscellaneous disorders. Several nuclear medicine techniques have proven to be valuable tools for guiding etiologic diagnosis in the setting of FUO. One of these is technetium-99m (Tc-99m)-hexamethylpropylene amine oxime (HMPAO)-labeled leukocyte scintigraphy, which is a diagnosis method that allows in most cases the localization and evaluation of the extension of an occult infection. This paper presents an uncommon case of pseudomembranous colitis without diarrhea as etiology of FUO diagnosed by Tc-99m-HMPAO-labeled leukocytes.

Keywords: Pseudomembranous colitis, fever of unknown origin, Tc-99m-HMPAO, single-photon emission computed tomography, radionuclide imaging


Informed Consent: Informed consent was obtained by patient.

Peer-review:Externally peer-reviewed.

Authorship Contribution

Surgical and Medical Practices: S.I-S., N.A., Concept: R.D.C.Z-I., Design: R.D.C.Z-I., J.F.P-G., Data Collection or Processing: R.D.C.Z-I., J.F.P-G., Analysis or Interpretation: R.D.C.Z-I., J.F.P-G., N.A-M., M.G-A., R.R-P., Literature Search: R.D.C.Z-I., M.G-A., Writing: R.D.C.Z-I., J.F.P-G.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.


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