Blue Rubber Bleb Nevus Syndrome
Blue Rubber Bleb Nevus Syndrome Causes
The causes of BRBNS are unknown. Most cases are sporadic, but there have been reports of autosomal dominance. The disorder has not been traced to a specific chromosome or gene defect. Not more than a few hundred cases have been described worldwide.
Blue Rubber Bleb Nevus Syndrome Definition
Blue rubber bleb nevus syndrome (BRBNS) is a syndrome characterized by multiple cutaneous venous malformations in association with internal venous lesions, most commonly affecting the bowel. BRBNS is an important syndrome because of it has the potential to result in serious or fatal bleeding.
Blue Rubber Bleb Nevus Syndrome Historical Background
Affected patients may present themselves to the dermatologist because of cosmetic concerns. Patients may note the increased amount of sweating on the skin overlying the lesion. There may also be physical complaints or varying symptoms depending on the organ system involved. Patients may report fatigue from blood loss. When bone is involved, patients may complain of joint pain or impaired walking. External lesions may also result in epistaxis, hemoptysis, hematuria, or menorrhagia. Patients may also present with blindness due to the cerebral or cerebellar cavernomas that may bleed internally into the occipital lobes.
Blue Rubber Bleb Nevus Syndrome Symptoms and Signs
No malignant transformation of cutaneous or internal lesions has been reported. Some patients may have severe bleeding from the GI tract (bowel), which can be fatal, while most bleeding from the GI tract is slow, minor, and chronic, resulting in iron deficiency anemia. Multiple transfusions and periodic observance can modify the morbidity of this disease. Lesions involving the bones and joints can cause profound discomfort and loss of function for the patient which would require amputations in some cases. In rare cases, central nervous system involvement can be fatal. Lesions may also appear on the patient's skin. Cutaneous lesions can often be seen at birth or they manifest early in childhood. These lesions are usually highly characteristic, as numerous, protruding, dark blue, compressible blebs, a few millimeters to several centimeters in diameter and varied in hue and shape, most of which are asymptomatic but some may be spontaneously painful or tender to the touch. They may be few or may reach hundreds. These lesions may appear blue, black, purple-red, or red and may be flat or elevated. Skin lesions rarely bleed unless they are traumatized. Progression in size and number of blebs may occur as the patient grows older. Lesions are mostly found on the skin and in the small intestine and distal large bowel. They may also occur in less common areas such as the nasopharynx, lungs, liver, heart, and brain.