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Blue rubber bleb nevus (BRBNS) is a rare vascular malformation disorder with cutaneous and visceral lesions frequently associated with serious, potentially fatal bleeding and anemia. More than 200 cases have been published so far, but prevalence is unknown. Multifocal venous malformations most commonly involve the skin and gastrointestinal tract (GIT), but can also affect the brain, kidneys, lungs, eyes, bones and other organs. Hemostatic abnormalities due to consumption coagulopathy and thrombocythemia have also been described. The lesions are generally present in childhood but can develop later in life. They are usually blue colored and easily compressible with light palpation. The main clinical manifestation is acute or chronic bleeding from the multiple GIT vascular malformations, with the small intestine usually being involved. The acute bleeding presents as hematemesis, melena, or rectal bleeding. Unless treated radically, patients with BRBNS develop anemia from chronic gastrointestinal bleeding and require lifelong treatment with iron and blood transfusions. Malignant transformation of the lesions has not been reported so far. Infrequent complications of the gastrointestinal malformations are volvulus, intussusception and intestinal infarction. The cause of the syndrome is still unknown. Although most cases show no apparent hereditary pattern, autosomal dominant expression has been reported in several families. A gene mutation has been mapped to the short arm of chromosome 9 and might be involved in these familial cases. Diagnostic methods include: blood counts, endoscopy, ultrasound, CT, MRI, and histopathology. Differential diagnoses include vascular tumors, either benign (hemangiomas) or malignant (Kaposi`s sarcoma, angiosarcoma); vascular anomalies associated with congenital or systemic diseases (Klippel-Trenaunay-Weber, Ehlers-Danlos, the CREST variant of scleroderma, and Osler-Weber-Rendu syndrome) and acquired and sporadic lesions (angiodysplasias, gastric antral vascular ectasia, radiation-induced vascular ectasias, and Dieulafoy`s lesions) (see these terms). Cutaneous lesions do not usually bleed: surgery, sclerotherapy or embolization provide a good cosmetic result. In the absence of massive GIT bleeding, a conservative treatment is sufficient (iron supplementation and/or blood transfusions). Corticosteroids, antifibrinolytic agents, high-dose intravenous gamma globulin and interferon alpha are of poor effect. Long-term use of octreotide has been found to reduce blood loss from BRBNS and other vascular gastrointestinal lesions. Intra-operative enteroscopy is the accepted ultimate diagnostic and/or therapeutic procedure, allowing immediate resolution of pathological findings by endoscopic coagulation or surgical full-thickness wedge excision. It is recommended to start with capsule wireless endoscopy to specify the indication for the procedure. Capsule endoscopy may also be a useful tool for monitoring the effects of therapy. |