Abstract and Introduction
Purpose of review To review the spectrum of lacrimal gland inflammation, with particular reference to the old condition, idiopathic dacryoadenitis, and the new, immunoglobulin G4 (IgG4)-related dacryoadenitis.
Recent findings Idiopathic dacryoadenitis remains the most common inflammatory lesion of the lacrimal gland, for which surgical treatment is successful. There is mounting evidence that the presence of IgG4-positive plasma cells in a lacrimal gland specimen is nonspecific, for being found in other inflammatory lacrimal gland lesions, even lymphoproliferative ones. To identify IgG4-related dacryoadenitis, particularly when there is no documented disease elsewhere, the criteria have been strengthened toward abundant IgG4-positive plasma cell counting.
Summary The gold standard of diagnosis of noninfectious lacrimal gland inflammation is tissue biopsying, which is commonly therapeutic in the case of idiopathic dacryoadenitis. Although it was initially suggested that IgG4-related dacryoadenitis is a possible cause of idiopathic dacryoadenitis, it becomes obvious that it has more resemblance to the lymphoproliferative tumors.
Approximately, half of the lacrimal gland mass lesions bear the histologic diagnosis of dacryoadenitis.[1,2] When interpreting the results of a biopsy, it is important to understand the architecture of the normal lacrimal gland. It contains immunoglobulin (Ig) A plasma cells, T cells, and a few B cells, occasionally organized in periductal lymphoid aggregates, with interlobular fibrosis. It belongs to the lymphoid tissue system referred to as mucosa-associated lymphoid tissue (MALT). With aging, increased focal infiltration by T and B cells, increased periductal and interacinar fibrosis along with acinar atrophy, dilated ducts and interlobular fatty infiltration becomes evident.
The lacrimal gland is often a primary target of the immune system, as a result of an autoimmune disorder, or unique to the lacrimal gland, as in the poorly understood idiopathic lesions. By contrast, the inflammation can originate from the immune response to an infection or a neoplastic process. In clinical practice, dacryoadenitis is a source of obscurity for it often lacks the inflammatory signs, and presents with enlargement only, and a source of confusion for it can be the symptom of a neoplastic lesion. This review discusses the main causes of lacrimal gland inflammation, classified as infectious, idiopathic, autoimmune, and lymphoproliferative. They differ across the age and sex groups, although many conditions can affect all (Fig. 1). There is no role for a diagnostic corticosteroid trial in any of these causes.
Curr Opin Ophthalmol. 2015;26(5):399-407. © 2015 Lippincott Williams & Wilkins