Pseudoxanthoma elasticum



Pseudoxanthoma elasticum


Kenneth H. Neldner and Mark G. Lebwohl


Evidence Levels:  A Double-blind study  B Clinical trial ≥ 20 subjects  C Clinical trial < 20 subjects  D Series ≥ 5 subjects  E Anecdotal case reports


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Pseudoxanthoma elasticum (PXE) is a rare autosomal recessive disorder causing abnormal calcification of the elastic fibers in the skin, retina, and cardiovascular system. The major clinical features include slightly thickened, leather-like skin lesions most commonly seen in flexural skin, retinal angioid streaks, and hemorrhages, with central vision loss. Cardiovascular problems are less common, intermittent claudication in the lower extremities being the most common finding. Gastrointestinal bleeding is reported in about 10% of patients, which may also be due to non-PXE related factors. The prevalence of PXE in the population is approximately 1 : 70 000. For unknown reasons there is an approximately 2 : 1 predominance in females.


The PXE gene(s) is located on chromosome 16p13.1 and a specific gene(s) has been identified in the ABCC6 group of genes.



Management strategy


Establishing the diagnosis of PXE may be difficult during the early stages of the disorder. The initial clinical signs appear most commonly during the early teenage years in flexural skin sites on the neck, axillae, antecubital fossae, and groin, as variably sized patches of slightly thickened, leathery-looking skin. The diagnosis is often missed during these early years. Larger patches gradually develop with age. Angioid streaks in the retina usually appear later, beginning in the late teens or early 20s. Frank retinal hemorrhages begin most commonly in the fifth decade, causing central vision loss. Cardiovascular changes are rarely noted in children, although rare cases have been reported. A heart healthy lifestyle including low cholesterol diet, aerobic exercises, and avoidance of smoking should be encouraged. Because of the bleeding diathesis in PXE, patients should be advised to avoid aspirin and other blood thinners unless essential. There is some evidence that increased dietary calcium results in more rapid progression of the disease. Therefore, patients should be encouraged to avoid calcium supplementation and excessive ingestion of milk products. An interdisciplinary approach involving dermatologists, retina specialists, and cardiologists is ideal.



Specific investigations






The tests are expensive and rarely essential to confirm the diagnosis.


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Aug 7, 2016 | Posted by in Dermatology | Comments Off on Pseudoxanthoma elasticum

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