Clinical characteristics: Pseudoxanthoma elasticum (PXE) is a systemic disorder that affects the elastic tissue of the skin, the eye, and vascular system. Individuals most commonly present with angioid streaks of the retina found on routine eye examination or associated with retinal hemorrhage and/or characteristic papules in the skin. The most frequent cause of morbidity and disability in PXE is reduced vision due to complications of subretinal neovascularizations and macular atrophy. Other manifestations include premature gastrointestinal angina and/or bleeding, intermittent claudication of arm and leg muscles, stroke, renovascular hypertension, and cardiovascular complications (angina/myocardial infarction). Most affected individuals live a normal life span.

Diagnosis/testing: The clinical diagnosis of PXE is established in a proband with characteristic skin lesions and at least one characteristic retinal finding. When eye findings are characteristic, but skin findings are equivocal, identification of calcified dystrophic elastic fibers using a von Kossa or similar stain on a biopsy of potentially lesional skin establishes the diagnosis.

The molecular diagnosis of PXE is established in a proband by the presence of biallelic ABCC6 pathogenic variants identified on molecular genetic testing.

Management: Treatment of manifestations: Management requires coordinated input from multidisciplinary specialists; care by a retina specialist including intraocular injection of anti-angiogenic drugs for the treatment of macular neovascularization when indicated; standard-of-care interventions for gastrointestinal bleeding, claudication, stroke, renovascular hypertension, and cardiovascular complications (angina and/or myocardial infarction).

Surveillance: Routine examination by a retina specialist; follow up as recommended by treating physicians for vascular manifestations.

Agents/circumstances to avoid: Contact sports or racquet sports without appropriate eye and head protection; aspirin and nonsteroidal anti-inflammatory medications because of increased risk of gastrointestinal bleeding; smoking because of its vasoconstrictive properties.

Pregnancy management: Vaginal delivery appears safe for the retina of women with PXE if no active choroidal neovascularization (CNV) is present. Women with PXE should have a retinal examination to check for active CNV, as angioid streaks alone are not an indication for medical interventions during delivery.

Genetic counseling: PXE is inherited in an autosomal recessive manner. At conception, each sib of an affected individual has a 25% chance of being affected, a 50% chance of being an asymptomatic heterozygote (carrier), and a 25% chance of being unaffected and not a carrier. If both ABCC6 pathogenic variants have been identified in the family, carrier testing for at-risk family members, prenatal testing for pregnancies at increased risk, and preimplantation genetic testing are possible.