Proteus Syndrome


Proteus syndrome is a rare complex condition, characterized by a variety of cutaneous and subcutaneous lesions including vascular malformations, lipomas, hyperpigmentation, and several types of nevi. The major clinical features of this rare vascular anomaly include verrucous nevus, lipomas and/or lipomatosis, macrocephaly, asymmetric limbs with partial gigantism of the hands and feet, and cerebriform plantar thickening. Partial gigantism with limb or digital overgrowth is pathognomonic. No racial or ethnic differences in disease occurrence appear to exist. Males and females are equally affected. Proteus syndrome may not be suspected in many individuals until later infancy or early childhood, depending on the degree of overgrowth or rate of cutaneous lesion appearance.

Associated Conditions (*):  

q       Hemihyperplasia, asymmetric overgrowth of limbs or digits, and megalospondylodysplasia

q       Scoliosis with or without unusual habitus

q       Macrocephaly, macroglossia, and cranial or auditory canal hyperostosis

q       Connective tissue nevi, epidermal nevi, lipomas, or vascular malformations

q       Clinically silent but locally invasive internal lipomas or vascular malformations

q       Pulmonary cystic malformations

q       DVTs, PEs, or both

q       Splenomegaly or thymic enlargement

q       Ovarian cystadenomas or parotid adenoma

q       Strabismus

q    Dental anomalies

q    Learning disabilities or mental retardation  

Findings (*):
q       When present at birth, asymmetric limb, digital, or cranial overgrowth may be a major diagnostic finding.  

q       Digital, limb, or cranial overgrowth usually involves both soft tissue and bone. Cranial or external auditory canal hyperostosis may be seen. Scoliosis associated with disproportionate vertebral growth is common.

q       The combination of disproportionate overgrowth and focal atrophy can lead to a unique habitus characterized by wasting of upper arm muscles, an elongated thorax, an extremely gracile neck, and muscular hypertrophy of the thighs.  

q       Cystic lung malformations leading to cystic pulmonary emphysema and restrictive lung disease secondary to severe scoliosis are relatively common. Recurrent pneumonias, shortness of breath, or reduced exercise tolerance may point to significant respiratory compromise. Organomegaly is less common but also can occur with splenomegaly or occasional thymus enlargement.  

q       Connective tissue nevi are virtually pathognomonic and typically have a cerebriform contour. They often occur on the soles of the feet but can also be found on other areas. Epidermal nevi tend to be the flat, soft variety.  

q       Lipomas may be well demarcated or locally invasive with large intra-abdominal or intrathoracic lesions presenting serious medical concerns.  

q       Vascular lesions may include capillaries, lymphatics, venules, or combinations of these. They tend to grow gradually over time and, unlike the more common capillary hemangiomas seen in the general population, rarely regress. Port wine stains or patchy hyperpigmentation also may be seen.  

q       Facial features that often coincide with poor mental development include a prominent occiput, ptosis with or without down-slanting palpebrae, upturned nose, and a long, narrow face

Diagnostic Studies: A baseline skeletal survey is recommended. MRI and CT may be used to evaluate possible head and intracranial abnormalities and also to evaluate associated vascular anomalies and lipomas. The characteristic MRI finding is abundant fat deposition in the malformation. MRA and MRV can elucidate the composition of focal masses and the underlying vascular anatomy. Pulmonary function tests may help evaluate patients with respiratory symptoms. An electroencephalogram is indicated for any patient with a history or symptoms suggesting seizures. Venograms, Doppler studies, or ventilation/perfusion (V/Q) studies may be helpful diagnostic tools in patients with symptoms suggestive of DVT or PE.

Management: Multidisciplinary approach is a must. Orthopedic complications often pose the most challenging medical problems, although vascular complications also contribute to overall morbidity.

Role of Interventional Radiology: Vascular malformations should be evaluated and managed by interventional radiologists. Transcatheter interventions such as embolization and sclerotherapy can be used in selected patients.

References: (*) eMedicine article by Dr. Beth A Pletcher


Contact          Disclaimer              Need help?