Case Presentation: A 62-year-old man traveled to Nicaragua. Sixty days into his vacation, he started to have visual disturbances. He had an ophthalmologic evaluation in Nicaragua and was diagnosed with uveitis. Upon returning to the United States, he pursued ophthalmology evaluation again. He denied history of autoimmune diseases and incarceration. His U.S. ophthalmologist diagnosed him with panuveitis and vasculitis bilaterally. The patient was then started on topical and oral glucocorticoids. A workup for uveitis was initiated, including testing for syphilis, autoimmune processes, HIV, ACE level, and Mycobacterium tuberculosis complex (TB) QuantiFERON testing. All results were unremarkable except for the QuantiFERON-TB test. Given that the patient had neither a known history of tuberculosis nor a positive TB IGRA (interferon-gamma release assay) test, he was referred for infectious disease consultation. Further detailed history revealed a cough, night sweats, and weight loss. Chest CT revealed the left posterior upper lobe to have a consolidation with cavitation changes. The patient was subsequently admitted to the hospital. Expectorated sputum samples collected for AFB smear, AFB culture and Mycobacterium tuberculosis (MTB) PCR. He was discharged on rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE) with steroids for uveitis. Following discharge, a sputum PCR for MTB was negative. Weeks later, one cultures identified M. abscessus (MAB); the second culture identified M. gordonae, and the last had no growth. Around 60 days after discharge, patient presented to eye clinic for follow-up. Though he reported improvement in his symptoms, his visual acuity had still not recovered fully to baseline.
Discussion: Ocular TB may present as an isolated condition.(1) However, it can also be a harbinger of underlying pulmonary TB.(2) Uveal inflammation is the most prevalent tuberculous injury of the eyes.(1)Diagnosing ocular TB is challenging. Obtaining ocular fluid for culture is difficult.(1) Although this patient was treated for MTB disease, the finding of MAB was unexpected. One may be tempted to treat the MAB; however, current guidelines state that MAB diagnosis require at least two positive cultures.(3) In this patient, the presence of MAB may have occurred after the primary infection (MTB) induced the cavitary lesion, a suitable environment for MAB.(4, 5) Interestingly, like MTB, MAB pulmonary disease may also present with a cavitation.(6) MAB ocular disease usually presents as keratitis after eye trauma.(7) The etiology of TB uveitis has been a point of debate. Some research suggests that it is due to a direct process where the mycobacteria are present in the eye causing disease, while others attribute ocular TB to a hypersensitivity reaction.(1, 8) Uveitis may present as anterior, posterior, or panuveitis.(9) Rapid initiation of TB treatment does appear to have better long-term outcomes.(10) The use of systemic steroids for TB uveitis is recommended.(9) Travel history is a critical for the evaluation of the TB patient.(11) Treatment of ocular TB typically involves starting RIPE.(12) There is a paucity of evidence to support using other regimens.(8)
Conclusions: Ocular TB is rare and may present alone or with pulmonary TB. High suspicion is needed to diagnose ocular TB, and such findings may also uncover pulmonary TB. The presence of more than one strain of mycobacteria on culture may not necessarily mean that all are pathogenic. A broad workup is essential to rule out all causes of uveitis.