Pseudoxanthoma Elasticum Flashcards
What is pseudoxanthoma elasticum (PXE)?
A rare genetic disorder affecting connective tissue, characterized by progressive calcification and fragmentation of elastic fibers in the skin, eyes, and blood vessels.
What tissues are primarily affected by PXE?
Skin.
Retina (Bruch’s membrane).
Cardiovascular system.
What is the primary cause of PXE?
Mutations in the ABCC6 gene, leading to dysfunction in elastin fiber maintenance.
Who is most commonly affected by PXE?
PXE can present in childhood or adolescence, with a higher prevalence in females.
What causes the elastic fibers to degenerate in PXE?
Mutations in ABCC6 impair cellular transport processes, leading to abnormal mineralization of elastic fibers.
How does PXE affect the vascular system?
Calcification and fragmentation of elastic fibers in blood vessels can lead to arterial stiffness, hypertension, and vascular occlusions.
What are the characteristic skin findings in PXE?
Yellowish, soft, coalescing papules resembling “plucked chicken skin.”
Commonly found on flexural areas such as the neck, axillae, groin, and periumbilical region.
How does PXE affect the eyes?
Angioid streaks: Breaks in Bruch’s membrane seen in the retina, leading to visual disturbances.
Risk of choroidal neovascularization, which can cause vision loss.
What are the cardiovascular manifestations of PXE?
Intermittent claudication due to peripheral arterial disease.
Hypertension.
Increased risk of myocardial infarction and stroke due to vascular calcifications.
Are there systemic symptoms associated with PXE?
No systemic symptoms directly caused by PXE, but its complications (e.g., vascular events) may lead to secondary systemic issues.
How is PXE diagnosed?
Clinical findings: Skin lesions and eye changes (angioid streaks).
Skin biopsy: Confirms calcification and fragmentation of elastic fibers in the dermis.
Genetic testing: Identifies mutations in the ABCC6 gene.
What imaging can help assess vascular complications in PXE?
Doppler ultrasound for peripheral arterial disease.
Echocardiogram to evaluate cardiovascular involvement.
What conditions should be considered in the differential diagnosis of PXE?
Cutis laxa: Generalized skin laxity without papules or angioid streaks.
Ehlers-Danlos syndrome: Hyperelastic skin and joint hypermobility
Is there a cure for PXE?
No, treatment focuses on managing symptoms and preventing complications
What skin treatments are used in PXE?
No specific treatments for skin lesions; cosmetic options (e.g., laser therapy) may be considered.
Avoid trauma to prevent skin ulceration.
How are ocular complications in PXE managed?
Regular ophthalmologic evaluations.
Anti-VEGF therapy (e.g., bevacizumab) for choroidal neovascularization.
What is the cardiovascular management for PXE?
Control of hypertension and hyperlipidemia.
Antiplatelet therapy to reduce the risk of vascular events.
Surveillance for peripheral arterial disease and other vascular complications.
What are the major complications of PXE?
Vision loss from choroidal neovascularization.
Peripheral arterial disease causing claudication.
Increased risk of myocardial infarction and stroke.
Gastrointestinal bleeding (rare).
What is the mode of inheritance of PXE?
Autosomal recessive.
