Chapter: Capillary malformations
Article: 11 of 14
Update: Mar 30, 2021
Author(s): Ott, Hagen
Where there is a pre-existing capillary malformation (CM), a benign vascular tumor known as granuloma pyogenicum can form more frequently in the capillary malformation of Sturge-Weber syndrome without an obvious trigger or after minor trauma than it can in otherwise healthy skin. In this context, BRAF mutations could be detected in the majority of investigated granulomas.
Dry skin and itchy reddened skin are also commonly observed on capillary malformations. These eczematous reactions also occur on pigmented moles and are then referred to as Meyerson phenomenon. A fragrance-free base cream can be used to treat the skin dryness. If itching persists, it can be treated with a cream containing cortisone. In this case, a low-potency active substance with a very favorable benefit/risk ratio should be used, especially in the very sensitive facial region (e.g., hydrophilic prednicarbate cream 0.08% 1x daily for a maximum of three to four days). For persistent eczema, a topical immunomodulator can be used to treat infants > 2 years of age (e.g., pimecrolimus cream 1% 2x daily for two to four weeks).
Nearly one-fifth of patients with isolated capillary malformation in the peri-orbital region and up to two-thirds of patients with Sturge-Weber syndrome develop secondary glaucoma. Pathological blood vessels may decrease the outflow of liquid from the anterior segment of the eye. As a result, intraocular pressure increases in infancy, which can lead to optic nerve impairment and ultimately blindness.
Other clinical signs of glaucoma include increased weeping of the affected eye, corneal opacification, and enlargement of the affected eyeball (buphthalmos). However, these late symptoms should not be awaited because of the threat of blindness. On the contrary, infants with peri-orbital capillary malformations should be referred promptly to a pediatric ophthalmologist for co-evaluation, further diagnostics and, if necessary, follow-up therapy.
Although capillary malformations often fade with age, in some cases they can also undergo a color change, becoming darker/purplish in particular, especially on the hands and face. This can make them more visible.
Reference has already been made to the rare possibility that tuberous hyperplasia and an increase in volume of the soft tissue can also occur under the capillary malformation over the course of many years, quite predominantly in the facial region.