proteus syndrome

Pathology

• hamartomatous disorder
• thick bundles of collagen in the papillary & reticular dermis

Genetics

• somatic-activating mutations of the AKT1 gene
• associated with defects in PTEN

Clinical manifestations

• overgrowth of multiple tissues
• connective tissue & epidermal nevi
  • plantar cerebriform collagenoma presents in 67% of patients
    • the most characteristic skin finding in Proteus syndrome
• vascular malformations
• manifestations usually apparent at birth or soon after & continue to develop as the patient ages
• case report
  • macrodactyly of hands & feet
  • lateral deviation of the affected fingers
  • disproportionate overgrowth of the right extremity
  • thoracolumbar scoliosis

* image of cerebriform plaques on both soles of feet

Laboratory

• PTEN gene mutation

Complications

• tumors, mostly benign but some malignant, have also been reported in proteus syndrome, generally presenting by the age of 20 years & including:
  • papillary adenocarcinoma of the testis
  • meningioma
  • cystadenoma of the ovaries

Notes

• named after the Greek god Proteus who, legend has it, could change his shape at will to avoid capture

More general terms

• genetic syndrome (multisystem disorder)

Database

• OMIM: https://mirror.omim.org/entry/176920