87
Other Vascular Disorders
This chapter covers a range of vascular disorders from livedo reticularis to common vascular ectasias such as venous lakes and telangiectasias. Additional disorders characterized by proliferation of blood vessels are covered in Chapters 85 (infantile hemangiomas and vascular malformations) and 94 (vascular neoplasms).
Livedo Reticularis
• Blue-violet netlike pattern that reflects an increase in deoxygenated blood within the venous plexus of the skin (Fig. 87.1); this increase can be due to a number of causes, including vasospasm of arterioles supplying the skin and sluggish flow due to hypercoagulability or luminal pathology.
Fig. 87.1 Anatomic basis for the development of livedo reticularis. At the edges of arterial cones, the venous plexus is prominent. An increase in deoxygenated blood within this plexus (due to a decrease in blood flow into or through the skin or impeded drainage of blood) leads to livedo reticularis. If disease of the feeding arteriole is suspected, a wedge biopsy of the central cone can be performed.
• A common physiologic vasospastic response to cold that resolves with rewarming, as well as a sign of a number of systemic diseases, from severe atherosclerosis to systemic lupus erythematosus (Table 87.1; Fig. 87.2).
Table 87.1
Causes of livedo reticularis.
DIC, disseminated intravascular coagulation; SLE, systemic lupus erythematosus.
Fig. 87.2 Livedo reticularis. A An even, netlike pattern is seen on the thigh in physiologic livedo reticularis. B In primary (idiopathic) livedo reticularis, the pattern persists with rewarming. C Livedo reticularis in a patient with SLE. A, B, Courtesy, Christopher Baker, MD, and Robert Kelly, MD; C, Courtesy, Jeffrey Callen, MD.
• DDx: early phase of erythema ab igne; viral exanthems (e.g. erythema infectiosum), retiform purpura and necrosis due to more complete disruption of blood flow (Fig. 87.3; see Chapter 18); underlying etiologies are outlined in Table 87.1.
Flushing
• Common etiologies are menopause, other causes of estrogen deficiency (e.g. tamoxifen), rosacea, and medications (e.g. nicotinic acid, nitrates); uncommon causes are carcinoid syndrome, mastocytosis, and pheochromocytoma (Table 87.2).
Table 87.2
Causes of flushing.
* With alcohol intake.
** Midgut tumors with liver metastases, type III gastric tumors, and bronchial tumors.
POEMS, polyneuropathy, organomegaly, endocrinopathy, M-protein (monoclonal gammopathy), skin changes; VIP, vasoactive intestinal polypeptide.
• Sites of involvement, primarily the face > ears, neck, and chest, are both visible and characterized by greater vasculature capacitance; an approach to the evaluation of a patient with flushing is outlined in Table 87.3.
