# Pseudoxanthoma Elasticum > Pseudoxanthoma elasticum for NEET-PG Dermatology covers ABCC6 mutation, plucked chicken skin, angioid streaks, vascular and GI complications and diagnosis. - Canonical URL: https://prepelephant.com/topics/neet-pg/dermatology/pseudoxanthoma-elasticum - Exam / course: NEET-PG · Subject: Dermatology - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-08 - Last updated: 2026-10-08 - Reference basis: Rook's Textbook of Dermatology; Fitzpatrick's Dermatology; Andrews' Diseases of the Skin - How to cite: "Pseudoxanthoma Elasticum", PrepElephant, https://prepelephant.com/topics/neet-pg/dermatology/pseudoxanthoma-elasticum ## Direct answer Pseudoxanthoma elasticum is an autosomal recessive disorder of elastic fibres caused by ABCC6 mutations, leading to calcified and fragmented elastic tissue in skin, eyes and blood vessels. Its skin marker is yellowish papules that coalesce in flexures to give a plucked chicken skin appearance. Angioid streaks, which are breaks in Bruch membrane, are the most important ocular feature and can cause central vision loss from choroidal neovascularisation. ## What you must remember - **ABCC6 gene:** located on chromosome 16p13.1 and encoding a membrane transporter expressed mainly in liver and kidney; most cases are autosomal recessive. - **Skin:** soft yellowish papules in the neck, axillae and groin that coalesce into plucked chicken skin; mucosal papules can appear in the mouth. - **Eyes:** angioid streaks predispose to choroidal neovascularisation and macular degeneration, and they often show on routine fundoscopy. - **Cardiovascular:** premature atherosclerosis, peripheral arterial disease, hypertension and gastrointestinal bleeding from fragile vessels. - **Histology:** fragmented, clumped and calcified elastic fibres in the dermis, positive on von Kossa and Verhoeff-van Gieson stains. - **Screening:** eye and blood pressure review are needed in every patient, because ocular and vascular disease drive morbidity. - **Management:** no curative therapy; control blood pressure, manage bleeding and treat choroidal neovascularisation with intravitreal anti-VEGF agents. ## A three-system diagnostic approach PXE is diagnosed by combining skin, eye and vascular findings, since no single feature is definitive. Work through the steps below and confirm with histology or genetics where needed. 1. **Recognise the skin:** look for small yellow papules in flexures that coalesce into a cobblestone or plucked chicken skin pattern. 2. **Examine the eyes:** perform fundoscopy and look for angioid streaks, which appear as dark lines radiating from the optic disc. 3. **Check the vessels:** measure blood pressure and assess for claudication, reduced pulses or gastrointestinal bleeding. 4. **Confirm histologically:** a punch biopsy showing fragmented, calcified elastic fibres that are von Kossa positive supports the diagnosis. 5. **Test the gene:** ABCC6 sequencing confirms the diagnosis and allows family screening. 6. **Plan monitoring:** arrange regular retinal review and cardiovascular risk assessment, since complications are progressive. Steps 2 and 4 carry the most diagnostic weight, because angioid streaks and calcified fibres on von Kossa staining are the findings most specific to PXE. ## Where the classic PXE stems mislead Most PXE questions combine skin and eye findings, so the traps lie in mixing up look-alike disorders. - **Trap:** choosing elastosis perforans serpiginosa for flexural yellow papules. **Correct:** PXE combines flexural papules with angioid streaks and vascular disease, which the perforating disorder lacks. - **Trap:** treating angioid streaks as a benign retinal finding. **Correct:** they predict choroidal neovascularisation and visual loss, so they warrant specialist review. - **Trap:** regarding the skin changes as purely cosmetic. **Correct:** vessel calcification drives premature atherosclerosis and gastrointestinal bleeding, which need active follow-up. - **Trap:** expecting a single curative drug. **Correct:** management is supportive and aimed at complications. ## Frequently asked questions ### Which gene is mutated in pseudoxanthoma elasticum? Pseudoxanthoma elasticum is caused by mutations in the ABCC6 gene on chromosome 16p13.1, which encodes a membrane transporter expressed mainly in liver and kidney. Loss of its function leads to calcification of elastic fibres in the skin, eyes and blood vessels. ### What is plucked chicken skin? Plucked chicken skin describes the coalescing yellowish papules with a crinkled, sagging texture seen in the flexures of patients with pseudoxanthoma elasticum. It is a clinical sign that prompts examination of the eyes and cardiovascular system. ### What is the most serious ocular complication of pseudoxanthoma elasticum? Choroidal neovascularisation secondary to angioid streaks is the most serious ocular complication of pseudoxanthoma elasticum, causing central visual loss. Intravitreal anti-VEGF agents are used to treat it, and early detection by retinal review improves outcomes. ### Which stains show the calcified elastic fibres in pseudoxanthoma elasticum? Von Kossa stain highlights the calcium deposits in the fragmented elastic fibres of pseudoxanthoma elasticum, while Verhoeff-van Gieson stain shows the fragmented elastic fibres themselves. Histology supports the diagnosis when skin and eye findings are equivocal. ### How does pseudoxanthoma elasticum affect the gastrointestinal tract? Fragile gastric and other mucosal vessels in pseudoxanthoma elasticum can bleed, causing occult or overt gastrointestinal haemorrhage. Patients need evaluation for anaemia and bleeding, along with blood pressure and vascular monitoring.