A 6-month-old African American boy is brought to his pediatrician for his six-month well-baby exam and immunizations. The mother asks whether the red mark on the forehead and right eyebrow from birth will ever go away (Figure 170-1). The pediatrician refers the child to a dermatologist that explains that this is a capillary malformation called a port-wine stain and that it will remain there for the rest of the child’s life. He also notes that it is less likely but still possible for this to be a salmon patch that could resolve spontaneously (although most salmon patches are lighter and midline). He states that it is not necessary to perform a biopsy because either way it is a capillary malformation that will not cause the child any physical harm. As it only involves part of V1 and none of V2, it is extremely unlikely to be part of the neurocutaneous syndrome known as Sturge-Weber syndrome. The pediatrician decides to not even bring up Sturge-Weber to avoid making the mother anxious but will continue to follow the child’s development over time. The dermatologist also explained that the child may choose to have laser treatment in the future if the capillary malformation is causing psychological distress.
FIGURE 170-1
Capillary malformation since birth on the forehead and right eyebrow of this 6-month-old infant. This is likely to be a port-wine stain since it is not midline and it is darker than most salmon patches. As it only involves part of V1 and none of V2 it is extremely unlikely to be part of the Sturge-Weber syndrome. (Used with permission from Richard P. Usatine, MD.)
Vascular malformations at birth range from the very common and benign salmon patch to rare but serious neurocutaneous syndromes (Sturge-Weber syndrome). Cutaneous lymphatic malformations are seen in a relatively rare condition called lymphangioma circumscripta. Osler-Weber-Rendu syndrome (hereditary hemorrhagic telangiectasia) is a rare vascular disorder that is inherited an autosomal dominant manner. Childhood hemangiomas are covered separately in Chapter 93, Childhood Hemangiomas.
There are two major types of capillary malformations present at birth:
Salmon patch (stork bite, angel kiss, capillary stain, nuchal nevus, nevus simplex, telangiectatic nevus, and nevus flammeus nuchae) is a superficial capillary malformation and is likely to resolve spontaneously (Figure 170-2). Using the term capillary stain is one-way to denote how superficial it is.
Port-wine stain (nevus flammeus) is deeper capillary malformation in the dermis and does not involute over time (Figure 170-3). In fact, it may increase in size, thickness, and become more nodular over time. It is this type of capillary malformation that may be associated with Sturge-Weber syndrome or Klippel-Trenaunay syndrome.
Microcystic lymphatic malformations are called lymphangioma circumscriptum or cutaneous lymphangioma circumscriptum (Figure 170-4).
FIGURE 170-4
Close-up of lymphangioma circumscriptum present from birth on the trunk of this 7-year-old girl. The vesicles vary in color from yellow to pink and red. The red color is due to blood within the dilated lymphatic vessels. Note how this pattern resembles frog spawn. (Used with permission from Richard P. Usatine, MD.)
Salmon patches, also known as “stork bites” or “angel kisses” are present in 26 to 64 percent of newborns.1–4 The angel kisses over the face tend to fade with time but the stork bites on the nape of the neck often persist (Figure 170-2).
Port-wine stains are congenital vascular malformations that occur in 0.6 to 2.8 percent of infants as developmental anomalies.3,4 They persist into adulthood. They may be associated with rare syndromes such as Klippel-Trenaunay and Sturge-Weber syndromes (see Chapter 207, Sturge-Weber Syndrome).
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal-dominant vascular disorder that affects one in several thousands of people (Figure 170-5). Certain populations in Europe and the US have a higher prevalence of this disease.5
Lymphangioma circumscriptum consists of dilated cutaneous lymphatic tissue and is rare.
FIGURE 170-5
Hereditary hemorrhagic telangiectasias (Osler-Weber-Rendu syndrome) in a teen with recurrent nosebleeds and visible telangiectasias on the lips and tongue. (Used with permission from Kane KS, Lio P, Stratigos AJ, Johnson RA. Color Atlas and Synopsis of Pediatric Dermatology, 2nd edition, Figure 10-10b, New York, NY: McGraw-Hill, 2009.)
Port-wine stains are vascular ectasias or dilations thought to arise from a deficiency of sympathetic nervous innervation to the blood vessels. Dilated capillaries are present throughout the dermis layer of the skin.
HHT is associated with mutations in two genes: endoglin on chromosome 9 (HHT type 1) and activin receptor-like kinase-1 on chromosome 12 (HHT type 2). These genes are involved in vascular development and repair. With the mutations, arterioles become dilated and connect directly with venules without a capillary in between. Although manifestations are not present at birth, telangiectasias later develop on the skin, mucous membranes, and GI tract. In addition, AVMs often develop in the hepatic (up to 70% of patients), pulmonary (5% to 300%), and cerebral circulations (10% to 15%). Any of these lesions may become fragile and prone to bleeding.5
Congenital malformations of the lymphatic system may involve the skin, subcutaneous tissues and intestines.6 These lymphangiomas are hamartomatous in nature with the most superficial version being lymphangioma circumscriptum. Deeper versions are called cavernous lymphangiomas and cystic hygromas. The dilated ectopic lymph vessels protrude from the skin forming vesicles.
