Abstract
Purpose::
To determine whether the onset of idiopathic orbital inflammation (IOI) demonstrated seasonal variation.
Methods::
A retrospective review of patients presenting to the Massachusetts Eye and Ear Infirmary with idiopathic orbital inflammation during a twelve year period. Charts were reviewed to determine the month of disease onset and the predominant manifestation of inflammation (myositis, dacryoadenitis, or other).
Results::
Between 1992 through 2004, 100 patients were identified with a diagnosis of idiopathic orbital inflammation for whom the month of onset could be clearly documented. Forty-five patients were men and 55 were women. Patients developed initial symptoms in winter (23%), spring (29%), summer (26%), and fall (22%). The most common manifestations were dacryoadentitis (41%) and myositis (35%). There was no statistically significant difference in season at presentation overall, or according to gender or inflammation subtype.
Conclusions::
Several population studies examining possible environmental triggers for immune-mediated diseases have found a seasonal pattern in presentation and symptoms. Specifically, season has been found to correlate with the incidence or exacerbation rates of diabetes mellitus, rheumatoid arthritis, Wegener’s granulomatosis, polymyalgia rheumatica, pemphigus, multiple sclerosis, inflammatory myopathy, and thyrotoxicosis. Investigations suggesting a link between seasonality and incidence of disease have focused on particular environmental precipitants of increased autoimmune activity such as sun exposure or microbial infections with seasonal prevalence.The primary question in our study was whether IOI would demonstrate a correlation between the incidence or specific locus of inflammation within the orbit and the time of year. Although other orbital autoimmune disorders have been examined, there are no such investigations regarding IOI and seasonality. Prior investigations of seasonal effects in other orbital inflammatory syndromes may have been limited by the fact that clinical manifestation may be subtle and nonspecific or relatively rare. IOI is characteristically dramatic in its signs and symptoms and it is straightforward to clearly define disease onset and therefore to examine temporal variations in incidence. Also, as the third most common primary orbital disease, IOI offers an adequate population to study. Despite these features, we did not uncover a seasonal pattern in the incidence or presentation of IOI.
Keywords: orbit • inflammation • autoimmune disease