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Visualization of Amyloid β Deposits in the Human Brain with Matrix-assisted Laser Desorption/Ionization Imaging Mass Spectrometry
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Disseminated superficial porokeratosis with amyloid deposits

Manuel Ginarte1, Alvaro León, Jaime Toribio

  • 1Department of Dermatology, Complejo Hospitalario Universitario de Santiago, Faculty of Medicine Santiago de Compostela, Spain. mginartev@medynet.com

European Journal of Dermatology : EJD
|July 29, 2005
PubMed

Insights

Porokeratosis lesions can contain amyloid deposits, which are often missed by standard stains. Routine use of special histochemical techniques could improve detection of amyloid in porokeratosis.

Area of Science:

  • Dermatopathology
  • Histology
  • Biochemistry

Background:

  • Porokeratosis is a rare epidermal nevus characterized by abnormal keratinization.
  • Amyloidosis is a group of disorders characterized by the deposition of amyloid protein.
  • The association between porokeratosis and amyloid deposition is not well-established.

Observation:

  • A 65-year-old Caucasian male presented with disseminated superficial porokeratosis.
  • Histological examination revealed eosinophilic amorphous material in dermal deposits.
  • This material stained positively with crystal violet and showed yellow fluorescence with thioflavin-T, confirming amyloid.

Findings:

  • Amyloid deposits can arise from degenerated colloid bodies within porokeratotic lesions.
  • Standard hematoxylin and eosin staining may not detect small quantities of amyloid.
  • Specialized histochemical stains are crucial for accurate amyloid identification.

Implications:

  • Routine use of histochemical techniques could increase the frequency of amyloid detection in porokeratosis.
  • This finding may have implications for understanding the pathogenesis of porokeratosis.
  • Further research is needed to explore the clinical significance of amyloid in porokeratosis.

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