The main lacrimal gland is an exocrine gland that contributes to the aqueous layer of the tear film. It consists of two major lobes, an orbital and a palpebral lobe, separated by the lateral extension of the levator aponeurosis. The orbital lobe is located in the lacrimal fossa of the orbit, and the palpebral lobe is located in the temporal portion of the superior fornix. Tears are excreted into the superior fornix via six to 12 lacrimal ductules that exit the palpebral lobe of the lacrimal gland. The lacrimal gland is highly vascularized and is innervated by sympathetic and parasympathetic nerves.

In his treatise on diseases of the lacrimal gland in 1803, Schmidt was the first to introduce the term dacryoadenitis in reference to inflammation of the main lacrimal gland (1). Dacryoadenitis is rare, with a reported incidence of approximately 1/10,000 ophthalmology visits (1, 2, 3, 4). Males and females are equally affected, except for gonococcal dacryoadenitis, where males outnumber females (2). Dacryoadenitis may affect all age groups.

Dacryoadenitis may be acute or chronic, infectious or noninfectious, primary or associated with a systemic disease. Infectious causes of dacryoadenitis include viral, bacterial, fungal, and parasitic organisms. The infection may be local or systemic. Associated, noninfectious systemic conditions include Sjögren syndrome, sarcoidosis, Crohn disease, and Wegener granulomatosis. Additionally, pseudotumors of the orbit may involve the lacrimal gland.

Acute dacryoadenitis is commonly unilateral and is usually caused by a local or systemic viral or bacterial infection. Patients present with acute pain and swelling of the lateral aspect of the upper eyelid. This may be accompanied by fever, malaise, and regional lymphadenopathy. Examination reveals eyelid edema, erythema, warmth, and occasionally proptosis and eyelid retraction (5). An S-shaped deformity of the upper lid is often noted. Induration, however, is characteristically absent. The lacrimal gland is usually enlarged and tender and the surrounding conjunctiva may be injected and chemotic. Abduction may be limited due to involvement of the lateral rectus muscle. Rarely, an abscess is detected (6,7). Vision is usually not affected.

Chronic dacryoadenitis is more commonly bilateral and may be caused by a noninfectious systemic disorder such as sarcoidosis or Sjögren syndrome. Less commonly, chronic dacryoadenitis is cased by a systemic viral infection such as mumps or the Epstein-Barr virus, or rarely by a granulomatous process such as tuberculosis or leprosy. Patients usually present with a painless mass in the superotemporal portion of the upper eyelid of several weeks’ to several months’ duration. Rarely, patients present with episodic upper eyelid swelling (8). Examination reveals ptosis if the lacrimal gland is significantly enlarged, and a firm, nontender mass in the area of the gland. Proptosis may be present, and the eye usually appears noninflamed.

Dacryoadenitis may be due to local or systemic infection, noninfectious systemic disease, orbital pseudotumor, or it may be idiopathic. Infectious causes of dacryoadenitis include bacteria, viruses, fungi, and parasites. Infectious agents reach the lacrimal gland through the lacrimal ductules, nerves, blood supply, or directly after trauma (3,4).

Mumps used to be the most common cause of viral dacryoadenitis (1,3,4,9). However, widespread mumps immunization campaigns have led to a decrease in the incidence of mumps and consequently mumps-associated dacryoadenitis (4,9). Dacryoadenitis secondary to mumps is more commonly acute but may be chronic and is usually bilateral.

Several authors have reported dacryoadenitis in association with, or as the presenting sign of, Epstein-Barr virus (EBV) infections and infectious mononucleosis (1,3,4,9, 10, 11, 12). Jones
(10) in 1955 deduced that one out of every 300 patients with infectious mononucleosis developed dacryoadenitis. In a more recent report by Rhem and colleagues (12), EBV accounted for approximately one third of all cases of dacryoadenitis seen over a 16-year period in a university practice. EBV dacryoadenitis is usually acute and bilateral. Chronic and unilateral cases have been reported, however. Clinical and laboratory evidence suggest a relationship between EBV infections and the development of primary Sjögren’s syndrome (13, 14, 15, 16, 17, 18, 19, 20, 21, 22).

In his manuscript on the etiology of dacryoadenitis published in 1955, Jones (10) reported a case of acute dacryoadenitis caused by herpes zoster infection. More recently, Obata and colleagues (23) reported a case of acute dacryoadenitis in a 30-year-old man associated with herpes zoster ophthalmicus. Herpes simplex viruses have also been associated with the development of acute dacryoadenitis (24). Herpes virus-related dacryoadenitis may be especially severe in immunocompromised patients.

A variety of bacteria have been associated with acute and chronic dacryoadenitis. Staphylococcus sp. are some of the most common bacterial cases of acute dacryoadenitis (1,3,4,9). Others include Streptococcus sp. and Treponema pallidum. Syphilitic dacryoadenitis may occur at any stage of the disease (3). Gonococcal infections of the lacrimal gland are usually acute, bilateral, and more common in males (2). The infectious agent reaches the lacrimal glands by direct extension from the conjunctiva, or by metastasis. Bekir and colleagues (25,26) from Turkey reported unilateral dacryoadenitis in a 16-year-old boy, and bilateral dacryoadenitis in a 34-year-old woman in association with systemic brucellosis. In a report published in 1997, Mawn and colleagues (27) described a case of pseudomonas dacryoadenitis secondary to a lacrimal ductule stone.

Chronic dacryoadenitis secondary to bacterial infections is rare. Tuberculosis is probably the most common bacterial cause of chronic dacryoadenitis (1,4,9,28). Sen (29) reported dacryoadenitis as the presenting manifestation of tuberculosis in one of 14 patients with tuberculosis orbital involvement. Madhukar and colleagues (30) reported a rare case of lacrimal gland abscess secondary to tuberculosis. The development of true dacryoadenitis secondary to trachoma is controversial (1). Fungal and parasitic infections of the lacrimal glands are exceedingly rare (1,4,9,31,32).