Orbital manifestations of hypercorticism

Abstract

Nowadays, Cushing's syndrome (hypercortisolism) and its manifestations are well studied. The main symptoms of hyper-cortisolism are obesity, osteoporosis, cardiomyopathy, muscle atrophy, skin thinning and purple stretch marks (striae) on the body. In practice, obesity and osteoporosis are the most frequent symptoms that are found in 90% of cases. However, there are some patients with an implicit clinical picture of hypercorticism. Some cases might concomitant with exophthalmos. This review describes a rare symptom of hypercortisolism — exophthalmos. Exophthalmos is a pathological protruding of eyeballs. This symptom is known in the context of TED that occurs most commonly in patients with Graves' disease. The article compares the mechanisms of development of eye symptoms in Cushing's syndrome and thyroid diseases, especially the Graves' disease. It discusses possible molecular mechanisms leading to exophthalmia in patients with Cushing's syndrome. Factors affecting adipogenesis in vitro and in vivo are studied, in particular factors leading to an increase of orbital fatty tissue against of elevated cortisol levels. Hormonal signaling and transcription cascades responsible for adipocyte differentiation into mature fat cells are presented. Other orbital manifestations of hypercortisolism, which occur relatively rare in practice, are also discussed in the article. These include glaucoma as well as cataract, Lisha nodules and central serous chorioretinopathy. Clinical cases of Cushing's syndrome with different ocular manifestations are considered and appropriate conclusions have been drawn.