Proteus syndrome

Proteus syndrome is a rare congenital, multisystemic, hamartomatous condition characterised by asymmetrical overgrowth of almost any part of the body and a broad spectrum of manifestations. It can affect tissue from any germinal layer. It is suspected to be a genetic condition, but a particular gene is not currently identified.

Affected patients usually appear normal at birth and progressively develop abnormalities in childhood. The progression usually stops after adolescence 1. The highly variable clinical manifestations frequently lead to initial misdiagnosis 3.

Common clinical manifestations include:

  • cerebriform connective tissue naevus: virtually pathognomonic
  • epidermal naevus
  • disproportional overgrowth: hemihypertrophy /partial gigantism 
  • macrodactyly
  • dysregulation of adipose tissue: lipoma, regional absence of fat, overgrowth of fat in the posterior/anterior body wall or un subcutaneous fat of the extremities
  • vascular malformations: capillary, venous or lymphatic

Less common findings include 1:

  • bilateral ovarian cystadenomas
  • parotid monomorphic adenoma
  • abnormal facial features, e.g. dolichocephaly, low nasal bridge, anteverted nares

Radiographic features are not specific and refer to any clinical characteristics. However, characteristically, Proteus syndrome is considered when there is hemimegalencephaly, extensive lymphangitic or vascular malformations and asymmetric hemihypertrophy 1

Other radiographic features include enlarged and dysplastic vertebral bodies, scoliosis, cranial exostosis, osteomas, osteochondromas, enchondromas and genu valgum may also occur.

The diagnosis is either suspected on clinical grounds or with a combination of radiologic abnormalities.

Differential diagnosis is mostly done on a clinical basis since most of the clinical manifestations are not specific. However, the differential diagnosis includes:

The name of this syndrome comes from the Greek god of the sea Proteus who had the ability to change his shape to avoid capture, it was proposed by Wiedemann et al. in 1983. The name thus refers to the unpredictable asymmetric gigantism/hemihypertrophy associated with this disease. The first case report (1884) of this disease is credited to Sir Frederick Treves regarding his famous patient, Joseph Merrick (known as the "Elephant Man") 5,6.

Share article

Article information

rID: 18869
Section: Syndromes
Synonyms or Alternate Spellings:
  • Wiedemann syndrome

Support Radiopaedia and see fewer ads

Cases and figures

  • Drag
    Case 1: with left facial hemi-hypertrophy
    Drag here to reorder.
  • Drag
    Case 2: with megalencephaly
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.