Erdheim-Chester Disease: Two cases from an ophthalmic perspective.

PURPOSE

We report two patients who presented initially to ophthalmology clinics with symptoms and signs of orbital inflammation that led to a diagnosis of Erdheim-Chester Disease (ECD).

OBSERVATIONS

ECD is a rare form of non-Langerhans cell histiocytosis (LCH) which is characterised by multi-system organ involvement and poor prognosis with standard therapies. Both patients were positive for the V600E mutation on genetic testing and were treated with the inhibitors Vemurafenib and Dabrafenib respectively. These cases highlight the variable clinical presentation and course of ECD, the classical radiological and histopathological findings, and the high degree of clinical suspicion necessary to reach this diagnosis.

CONCLUSIONS AND IMPORTANCE

The combination of xanthelasma and bilateral, diffuse intraconal orbital masses must suggest to the clinician the possibility of ECD; and consideration to arrange further investigation with a full body CT or FDG PET/CT scan should be given, even in the absence of wider systemic symptoms or signs. With the advent of targeted therapies such as inhibitors, it is of even more importance that a diagnosis of ECD is established in a timely manner in order to give these patients the best chance of reduced morbidity and increased survival.