Granulomatous Iritis (Anterior Uveitis) Workup

Updated: Sep 19, 2018
  • Author: Andrew A Dahl, MD, FACS; Chief Editor: Hampton Roy, Sr, MD  more...
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Laboratory Studies

Findings from the physical examination, a comprehensive review of the patient's medical history, and the review of systems should guide the laboratory evaluation. The workup should be tailored accordingly.

All patients who present with a granulomatous iritis should receive a diagnostic evaluation, even if it is their first episode of uveitis.

Laboratory tests that may be requested are outlined below. At the least, chest radiography and fluorescent treponemal antibody absorption (FTA-ABS) or other specific antitreponemal syphilis serology should be ordered.

Laboratory tests are as follows:

  • Purified protein derivative (PPD) test or Quantiferon testing for TB

  • Chest radiograph for sarcoidosis and TB should be obtained. However, the chest radiograph is not very sensitive or specific for sarcoidosis and a high-resolution chest CT should be considered if sarcoidosis is strongly suspected. Gallium scan can also be considered for sarcoidosis.

  • Venereal Disease Research Laboratory (VDRL) test, FTA-ABS (or similar treponemal specific serology) test for syphilis A specific antitreponemal test must be obtained, as RPR or VDRL can provide false-negative results on RPR or VDRL.

  • CBC with differential

  • Angiotensin-converting enzyme (ACE) test for sarcoidosis may be obtained but is not very sensitive or specific, especially in children.

  • Anergy evaluation for sarcoidosis (rarely done)

  • Lyme serology if Lyme disease is suspected (eg, endemic area, tick bite, systemic manifestations)

  • Toxoplasmosis enzyme-linked immunosorbent assay (ELISA) if posterior uveitis associated

  • Antineutrophil cytoplasmic autoantibodies: c-ANCA with PR3 specificity is most specific for Wegener granulomatosis. c-ANCA is found in 80-95% of active cases. An isolated anterior uveitis (without orbital, scleral, or corneal involvement) is a very rare presentation of Wegener granulomatosis.

  • Cytology, polymerase chain reaction, and cultures of intra-ocular fluid when infection or masquerade suspected

  • In cases of suspected ARN, anterior chamber fluid and/or vitreous should be examined via polymerase chain reaction (PCR) for HSV and herpes zoster virus nucleic acid.


Imaging Studies

MRI of the head may help in suspected cases of intraocular (CNS) lymphoma or in cases of multiple sclerosis; however, this is a rare cause of granulomatous anterior uveitis (multiple sclerosis is more commonly associated with intermediate uveitis and lymphoma with vitritis or subretinal lesions).

In patients in whom sarcoidosis is suspected and in whom chest radiographs are negative for disease, consider chest CT to look for hilar adenopathy. Up to 10% of patients with sarcoidosis who have negative chest radiographs may exhibit hilar pathology on chest CT. [6]

Ultrasonography (B scan) of the eye is performed if the posterior segment cannot be seen.



Biopsy of any conjunctival nodules or the lacrimal gland may help in diagnosing sarcoidosis.

Vitreous biopsy may be indicated if a diagnostic dilemma exists and infection or masquerade syndrome is suspected; a specific tissue diagnosis, culture findings, or polymerase chain reaction results may alter or direct therapy.

Lumbar puncture may be required to help rule out intraocular (CNS) lymphoma.

If the patient presents with a secluded pupil from extensive posterior synechiae, iris bombe with angle-closure glaucoma may be present. Perform iridotomy as soon as possible (after quieting the eye with anti-inflammatory medications).


Histologic Findings

Mutton fat KPs: These consist of accumulation of macrophages but are not necessarily true granulomas.

Iris nodules: Histopathologic examination of the iris nodule has revealed abundant lymphocytes and plasma cells with areas of chronic granulomatous inflammation. However, not all iris nodules, including those that may be associated with granulomatous disease in some cases (eg, Koeppe nodules), are necessarily granulomas.