Detection of cutaneous prion protein deposits could help diagnose GPI-anchorless prion disease with neuropathy

Background and purpose: To investigate prion protein (PrP) deposits in cutaneous tissues of patients of glycosylphosphatidylinositol (GPI)-anchorless prion diseases with neuropathy.

Methods: Cutaneous tissue samples from three patients with GPI-anchorless prion diseases were obtained, two cutaneous biopsy samples from the lower leg of Case 1 (Y162X) and Case 3 (D178fs25), and a cutaneous sample taken from the abdomen during an autopsy of Case 2 (D178fs25). We performed immunohistochemistry for PrP to look for abnormal PrP deposits.

Results: PrP deposits were observed in the dermal papilla, the sweat glands, the hair follicles, the arrector pili muscles, and peripheral nerves of all examined cases of GPI-anchorless prion disease with neuropathy. The abnormal PrP accumulation was frequently localized at the basement membrane, and colocalized with laminin.

Conclusion: Immunohistochemical detection of PrP in cutaneous samples could be used to definitively diagnose GPI-anchorless PrP disease with neuropathy.