Disorder of patchy/mosaic postnatal growth dysregulation (primarily involving overgrowth) of unknown aetiology.
Somatic genetic activation mutation of the AKT1 gene
Disorder primarily manifests as postnatal overgrowth, with irregular, distorting and progressive overgrowth that can include many tissues in a patchy/mosaic pattern.
- Typically asymmetric and location varies remarkably
- Commonly involved tissue:
- Connective tissue and bone
- Other tissue:
- Central nervous system & eye
- Other tissues
- Most cases born without significant asymmetry and asymmetric overgrowth starts in the 6–18 months age range
- Rapidly progressive growth (rate of overgrowth rapidly becomes disproportionate between body parts)
- Deep venous thrombosis (DVT)
- Pulmonary embolism
- affected bones can become unrecognizably distorted.
Revised PS diagnostic criteria
- Fibrolipomatous hamartoma
- Macrodystrophia lipomatosa (ML)
- Rare congenital disorder characterized by localised overgrowth of a part of an extremity or less commonly a whole extremity
- Neurofibromatosis type 1 (NF1)
- NF1 symptoms include light brown spots on the skin, freckles in the armpit and groin, small bumps within nerves, and scoliosis. NF tumors are generally non-cancerous.
- Klippel–Trénaunay syndrome or angioosteohypertrophy syndrome or hemangiectatic hypertrophy
- Rare congenital medical condition in which blood vessels and/or lymph vessels fail to form properly
- 3 main features:
- Nevus flammeus
- Venous and lymphatic malformations
- Soft-tissue hypertrophy of the affected limb
- Parkes Weber syndrome (PWS)
- Extremely rare congenital disorder of the vascular system, named after British dermatologist Frederick Parkes Weber, who first described the syndrome in 1907.
- Usually benign tumours derived from blood vessel cells and can occur anywhere on the body, but most commonly appears on the face, scalp, chest or back.
- M/C form: Infantile hemangioma “strawberry mark”
- Seen on the skin at birth or in the first weeks of life