Vascular proliferations and abnormalities of blood vessels
Terminology of vascular conditions can be confusing, with several lesions being incorrectly named or classified. Vascular skin lesions include:
A paediatric dermatologist, paediatrician, vascular specialist or surgeon should assess significant infantile capillary malformations or proliferative haemangiomas, especially when large, symptomatic (eg ulcerated), located on the head and neck or close to eye, nose or mouth.
Vascular naevi or anomalies are present at birth or appear in early childhood. They are classified according to the size and type of vessel. They may remain stable or become more prominent with maturity. There are various associated syndromes.
- Capillary malformation – salmon patch and port wine stain.
- Venous maliformations – glomovenous malformation, arteriovenous malformations, blue rubber bleb syndrome (associated gastrointestinal lesions).
- Arteriovenous malformations: of mixed blood vessel origin
- Lymphatic malformation: lymphangioma circumscriptum, cavernous lymphangioma
- Angioma serpiginosa: a crop of swirling vascular papules
- Naevus anaemicus – in this naevus, blood flow is interrupted resulting in pale areas.
Angiomas are benign tumours formed by dilation of blood vessels or formation of new ones by proliferation of endothelial cells.
- Infantile proliferative haemangioma (capillary, cavernous or mixed): proliferates in the first few weeks of life, followed by involution later in childhood. These are sometimes syndromic, as in PHACES, LUMBAR and PELVIS syndromes.
- Congenital haemangioma is at full size at birth and may rapidly involute (RICH) or persist (NICH)
- Kaposiform hemangioendothelioma is a rare aggressive haemangioma that results in platelet trapping — the Kasabach-Merritt phenomenon.
- Tufted angioma: rare childhood tumour with characteristic histology.
- Cherry angioma: adult onset, common degenerative lesions, usually multiple
- Angiokeratoma: acquired scaly angiomas, usually on vulva or scrotum, or in association with Fabry disease
- Glomus tumour: tender papule on nail bed or palm arising in young to middle-aged adult
- Venous lake: blue or purple compressible papule due to venous dilation, often on lower lip or ear.
Pyogenic granuloma occurs in children and young adults on skin and mucosa, most often lower lips, fingers and toes in response to a minor, often unnoticed, injury. It grows rapidly and may become pedunculated or polypoid and surrounded by collarette of normal skin. It bleeds and crusts.
Bacillary angiomatosis is a rare opportunistic bacterial infection due to Rochalimaea henselae.
Prominent cutaneous blood vessels can be physiological or pathological (eg feeding a tumour such as basal cell carcinoma, a common sign of rosacea, and required to make the diagnosis of the CRST variant of systemic sclerosis and the telangiectasia eruptiva macularis perstans form of mastocytosis). There are some named conditions in which telangiectasia is (or telangiectases are) characteristic.
- Spider angioma or spider telangiectasis consists of central arteriole and radiating capillaries. Very common in healthy individuals, but more arise in response to oestrogen, eg pregnancy, liver disease.
- Unilateral acquired telangiectasia: telangiectasia with naevoid distribution.
- Essential telangiectasia: idiopathic telangiectasia and venulectasia.
- Benign hereditary telangiectasia: familial condition in which matt telangiectases appear
- Hereditary haemorrhagic telangiectasia: telangiectasia on skin and mucous membranes associated with bleeding from nose and gut causing anaemia.
- Acquired lymphangiectasia; “frog-spawn” appearance that follows lymphatic obstruction eg tumour or surgery.
- Kaposi sarcoma: due to Human herpesvirus 8 (HHV8) and immunosuppression, eg infection with human immunodeficiency virus (HIV). There are 4 types lead to multiple purple macules, papules and plaque on skin and mucous membranes.
- Angiosarcoma: idiopathic or secondary to chronic lymphoedema or radiation. Often an aggressive cancer, it mostly presents in elderly people with spreading purple patches and plaques that may bleed and ulcerate.
- Intravascular B-cell lymphoma presents with rapid-onset irregular telangiectases.