A 38 year old male from Ukraine presented for a glasses exam. He reported having macular degeneration OD and poor vision OS for unclear reasons. He also reported a history of “eye injection” OS many years ago. Patient is healthy on no medications.
OS CF, PH:CF
Anterior segment was WNL OU
The most important finding is subtle…
Is there anything else you would like to look at?
Hint: it’s a skin lesion characteristic of this condition.
The patient was unaware of the following skin lesion.
What’s your diagnosis?
1. By now you should have a popular Mnemonic in mind for the differential diagnosis
2. The skin lesion tells you which of the differential is most likely
Let’s look at the pictures together.
Have you noticed these subtle lines? This is the key finding.
The left eye has a large fibrotic scar that is located below the retina (below because the overlying vessels are visible) which fits the underlying diagnosis which is…. Angioid Streaks!
Angioid streaks are abnormal, visible cracks in Bruch's membrane, these streaks appear as SUBTLE dark lines radiating from the optic nerve. It is often associated with an underlying systemic conditions with the popular Mnemonic PEPSI.
P: Pseudoxanthoma elasticum (PXE)
E: Ehlers-Danlos syndrome
P: Paget's disease
S: Sickle cell anemia
Pseudoxanthoma elasticum (PXE) is by far the most common cause of Angioid streaks. PXE is an inherited recessive genetic disorder that affects the connective tissues in various parts of the body, including the skin, eyes, and blood vessels.
Our patient presented with a classic lax and redundant skin finding on his neck, however this finding can also be found in any other areas where the skin folds such as the armpit, joints and groin.
PXE causes calcification and fragmentation of elastic fibers that leads to cracks in Bruch’s membrane called “Angioid Streaks”.
Complications of breaks in Bruch’s membrane include:
=> choroidal neovascularization
=> subretinal hemorrhage
=> subretinal scarring
Note: Our patient initially reported a history of “eye injection” OS which is indicative of a previous history of CNVM which ultimately led to a subretinal scar and poor visual acuity.
Unfortunately there is no cure for PXE; the main symptomatic treatments are vascular endothelial growth factor inhibitor therapy (Anti-Vegf) (for ophthalmic manifestations), lifestyle, lipid-lowering and dietary measures (for reducing vascular risk factors), and vascular surgery (for severe cardiovascular manifestations). Future treatment options may include gene therapy/editing.
I hope you enjoyed this case!