There are two schools of thought:
- One, that a diagnosis of orbital and ocular adnexal sarcoidosis should be made only in patients with evidence of systemic disease (Mombaerts 1996). Accordingly, isolated orbital and/or adnexal granulomatous inflammation, consistent with sarcoidosis, without evidence of systemic sarcoidosis, is considered a variant of idiopathic orbital inflammation.
- The second school of thought allows for a diagnosis of sarcoidosis limited to the orbit and ocular adnexa. In a retrospective review of 379 sarcoidosis patients managed by the Department of Ophthalmology at the Henry Ford Hospital in Detroit from 2000 to 2008, 30 patients had orbital and adnexal sarcoidosis (Demirci 2011).
- Systemic sarcoidosis was detected in only 70% (21/30).
- Systemic disease was evident before periocular presentation in only 11 of 30 (37%), and was discovered in another 8 at the time of the diagnosis.
- In 2 patients the systemic presentation was evident after the periocular presentation (7%) 9 may have had subclinical systemic disease.
Among 20 patients diagnosed with orbital sarcoidosis in Vancouver from 1976 to 2005 only 50% had evidence of systemic disease on follow-up (Mavrikakis 2007).
In a review of 532 systemic sarcoidosis patients, 10% had orbital and adnexal involvement, so it is fairly common among systemic sarcoidosis patients (Obenauf 1978).
Among ophthalmic sarcoidosis patients in Boston, 10% had orbital/adnexal involvement similar to the Detroit experience (Smith 1996).
The classic ocular involvement of systemic sarcoidosis with uveitis and retinal vasculitis most commonly does not occur in the same patient who develops orbital and adnexal disease. In a multicenter study of 26 patients with orbital and adnexal sarcoidosis, 6 had anterior uveitis at diagnosis, prior to diagnosis, or on follow-up (Prabhakaran 2007).
Eiology
Sarcoidosis seems to be an exaggerated granulomatous reaction to unidentified antigen(s) in individuals who are genetically susceptible (Valeyre 2014).
Two suspected infectious agents linked to sarcoidosis are mycobacteria (Haupert 1997) and propionibacteria (Eishi 2013).
- There is no evidence that it is an infectious disease.
- Killed or partly degraded pathogens seem to trigger the immune response.
- The high lipid content in the cell membranes of these 2 infectious agents make them resist degradation.
- Resistance to degradation is a constant in sarcoidosis.
The antigens in partly degraded mycobacteria and propionibacteria have "trigger patterns" that bind to trigger pattern receptors: Toll-like receptors 2 and 9, C-type lectins, and NOD-like receptors.
Macrophages typically suppress the effector T-cell response, whereas macrophages from patients with sarcoidosis have antigen-presenting capacities and are hyper-reactive to certain ligands.
Non-necrotizing granulomas are thought to trap remnants that cannot be further degraded. In the progressive disease, the antigen is postulated to persist, thereby inducing a chronic immune response.
A predisposing genetic background determines the course of the disease (Rybicki 2001).
- HLA- DRB1*03 predisposes to disease with spontaneous resolution (Ishihara 1995).
- HLA-DRB1*14 or HLA-DRB1*15 are predisposing for a chronic course.
Other organic and inorganic substances might also trigger sarcoidosis (Chen 2008).
Epidemiology
The lacrimal gland and orbit are involved about equally (each 40%) (Prabhakaran 2007). The eyelid and lacrimal sac are involved less frequently (each 10%).
It is commonly bilateral (about 25%).
It is most common in the fifth and sixth decade of life:
- Wide range of presentation from third to ninth decade
- Pediatric presentation rare
Patients with orbital and adnexal disease are commonly Caucasian (Evans 2007). This differs from patients with primarily systemic disease (Prabhakaran 2007).
There is no gender predilection.
The systemic sarcoidosis incidence in the US is estimated at 36 in 100,000 for the African American population (Iannuzzi 2007). It is about 3-4 times more common in African Americans than Caucasians.
There is lung involvement and mediastinal lymphadenopathy in 85–90% of cases.
A high incidence of sarcoidosis was reported in firefighters and other responders after the attacks on the World Trade Center (Perlman 2011).
History
The most common presenting complaint is a palpable periocular mass (Prabhakaran 2007). Other complaints include:
- Lacrimal gland enlargement
- Medial canthal mass
- Another periocular area
- Proptosis
- Ptosis
- Dry eye
- Diplopia
- Decreased vision
- Dacryocystitis: lacrimal sac involvement (Harris 1981).
- Epiphora: nasal mucosal and sinus involvement
Cinical features
Sarcoidosis occurs almost exclusively in the anterior orbit.
- 97% had anterior, not mid- or posterior, orbital disease in one study study (Demirci 2011).
- Mostly superior and extraconal
In skin, sarcoidosis can be similar to molluscum lesions with flesh colored nodules and umbilicated centers (Hall 1995). Umbilication can progress to destructive lesion (Moin 2001).
Unusual presentations include vision loss due to optic nerve sheath involvement (Mavrikakis 2007).
Infiltration can involve extraocular muscles (Stannard 1985). Can present as painful external ophthalmoplegia (Cornblath 1993)
Heerfordt syndrome is uveitis, parotid gland enlargement, chronic fever, and facial paralysis:
- Originally described as a manifestation of mumps
- Now considered a rare presentation of sarcoidosis
- Not related to orbital and adnexal sarcoidosis
Testing
- Biopsy of ocular adnexal tissue shows typical sarcoidal granuloma with epithelioid histiocytes and scattered giant cells. The tissue can be surrounded by lymphocytes or "naked" granuloma.
- Chest x-ray demonstrates hilar lymphadenopathy with or without parenchymal involvement in 60–70% of cases.
- Serum angiotensin converting enzyme (ACE) is elevated in 60%.
- Gallium scintigraphy can demonstrate additional areas of lymphadenopathy.
- Serum lysozyme
- Serum calcium
- Serum liver function tests
- Biopsy areas of inflammation or granuloma
Testing for staging, fundamental impairment
There is no staging system for this disease.