Presumed tuberculous uveitis in a university-based tertiary referral center in Saudi Arabia

The immune response in tubercular uveitis and its implications for treatment: From anti-tubercular treatment to host-directed therapies

Tubercular uveitis (TB-uveitis) remains a conundrum in the uveitis field, which is mainly related to the diverse clinical phenotypes of TB-uveitis. Moreover, it remains difficult to differentiate whether Mycobacterium tuberculosis (Mtb) is present in the ocular tissues, elicits a heightened immune response without Mtb invasion in ocular tissues, or even induces an anti-retinal autoimmune response. Gaps in the immuno-pathological knowledge of TB-uveitis likely delay timely diagnosis and appropriate management. In the last decade, the immunopathophysiology of TB-uveitis and its clinical management, including experts' consensus to treat or not to treat certain conditions with anti-tubercular treatment (ATT), have been extensively investigated. In the meantime, research on TB treatment, in general, is shifting more toward host-directed therapies (HDT). Given the complexities of the host-Mtb interaction, enhancement of the host immune response is expected to boost the effectiveness of ATT and help overcome the rising burden of drug-resistant Mtb strains in the population. This review will summarize the current knowledge on the immunopathophysiology of TB-uveitis and recent advances in treatment modalities and outcomes of TB-uveitis, capturing results gathered from high- and low-burden TB countries with ATT as the mainstay of treatment. Moreover, we outline the recent progress of HDT development in the pulmonary TB field and discuss the possibility of its applicability to TB-uveitis. The concept of HDT might help direct future development of efficacious therapy for TB-uveitis, although more in-depth research on the immunoregulation of this disease is still necessary.

Anti-tubercular therapy in the treatment of tubercular uveitis: A systematic review and meta-analysis

We quantitatively evaluated the efficacy of antitubercular therapy (ATT) in tubercular uveitis (TBU) patients. Main outcome measures include inflammation recurrence, inflammation reduction, complete resolution of inflammation, improved visual acuity (VA), ability to taper corticosteroids to < 10 mg/day without inflammatory progression, and use of adjunctive immunosuppressants while on ATT. This review is prospectively registered in PROSPERO (CRD42020206845). Forty-nine studies reporting data for 4,017 TBU patients were included. In comparative studies, the odds ratio (OR) of inflammatory recurrence was 0.33 (95%CI:0.19-0.60) for TBU patients treated with ATT±corticosteroid versus no ATT. For TBU patients treated with ATT±corticosteroid, the pooled absolute incidences of inflammatory recurrence, inflammatory reduction, complete resolution of inflammation, and visual acuity improvement were 13% (n=310/2,216; 95%CI:9-18), 81% (n=217/276; 95%CI: 62-95), 83% (n=1,167/1,812; 95%CI: 77-89), and 65% (n=347/542; 95%CI:51-78), respectively. Corticosteroids were tapered to <10 mg/day without inflammatory progression in 91% (n=326/395; 95%CI:78-99) of patients, 9% (n=121/1,376; 95%CI:6-13) of whom were administered concomitant immunosuppressive agents alongside ATT. We conclude that treatment of TBU with ATT±corticosteroid is associated with a high level of control or improvement of inflammation. More prospective studies with detailed reporting of ATT regimens, patient subgroups, and outcomes are required to better evaluate ATT effectiveness.

Prognosis of Ocular Tuberculosis Following Long-Term Antitubercular Therapy

Purpose: This study presents clinical features and prognosis after long-term (12-18 months) antitubercular therapy (ATT) in patients with ocular tuberculosis (OTB) in East China, an endemic area of tuberculosis. Methods: This retrospective study reviewed data from OTB patients treated at the Eye and ENT Hospital of Fudan University from 2008 to 2018. All the patients completed a minimum follow-up of 6 months after the cessation of ATT. Results: Sixty-six patients with OTB were studied. The ocular manifestations included retinal vasculitis (51.6%), choroiditis (24.2%), panuveitis (23.2%), intermediate uveitis (7.4%), scleritis (5.3%), anterior uveitis (2.1%), and optic neuropathy (1%). Except for two patients (ATT for 6 months), all other patients (64/66, 96.97%) received ATT for at least 12 months (6 patients for 12 months, 30 patients for 15 months, and 28 patients for 18 months). Treatment in conjunction with oral corticosteroids was used in 48 patients (72.7%). The average initial best-corrected visual acuity (BCVA) was 0.8 ± 0.64 (LogMAR), which improved to 0.31 ± 0.35 (LogMAR) at the last follow-up (P < 0.05). The final BCVA was significantly associated with the initial BCVA and the duration of clinical symptoms. A complete remission of uveitis was achieved in 97% of the patients. Conclusions: This study observed a favorable prognosis with long-term ATT regimens. Patients with better baseline visual acuity and a shorter duration of clinical symptoms before diagnosis had a better prognosis.

Indocyanine green angiographic findings in presumed intraocular tuberculosis

PURPOSE

To study features of Indocyanine green angiography (ICGA) in patients with presumed intraocular tuberculosis.

METHODS

Retrospective study of 48 consecutive patients (77 eyes) who underwent ICGA. The following signs were analysed: choroidal perfusion inhomogeneity, early hyperfluorescent stromal vessels, round or oval hypofluorescent dark dots (HDDs), hypofluorescent geographic lesions (HGLs), fuzzy or lost pattern of large stromal choroidal vessels, disc hyperfluorescence and diffuse late choroidal hyperfluorescence.

RESULTS

Among 44 eyes of 29 patients with no clinical evidence of choroidal involvement, only 7 eyes of 6 patients had no ICGA evidence of choroidal involvement. On the other hand, ICGA findings suggesting choroidal involvement were noted in 37 (84.1%) eyes of 23 patients in the form of HDDs in all 37 (100%) eyes, HGLs in 7 (18.9%) eyes, disc hyperfluorescence in 20 (45.5%) eyes, fuzzy stromal vessels in 17 (38.6%) eyes, early hyperfluorescent stromal vessels in 13 (29.5%) eyes, late pinpoint hyperfluorescence in 11 (25%) eyes and late diffuse choroidal hyperfluorescence in 7 (15.9%) eyes. Among 33 eyes of 19 patients with clinically evident choroidal involvement, the following findings were identified; HDDs in 12 (36.4%) eyes, HGLs in 10 (30.3%) eyes, both HDDs and HGLs in 9 (27.3%) eyes, disc hyperfluorescence in 11 (33.3%) eyes, early hyperfluorescent stromal vessels in 7 (21.2%) eyes, fuzzy stromal vessels in 6 (18.2%) eyes and late diffuse choroidal hyperfluorescence was present in 2 (6.1%) eyes.

CONCLUSIONS

ICGA is necessary in identifying and diagnosing subclinical tuberculous choroidal involvement. The most prevalent ICGA finding was persistent HDDs.

The Collaborative Ocular Tuberculosis Study (COTS)-1: A Multinational Review of 165 Patients with Tubercular Anterior Uveitis

PURPOSE

The Collaborative Ocular Tuberculosis Study (COTS) Group sought to address the diagnostic uncertainty through retrospective cohort analysis of treatment regimens and therapeutic outcomes for patients with tubercular Anterior Uveitis (TAU) across international centers.

METHODS

Multicentre retrospective analysis of patients diagnosed with TAU between January 2004 to December 2014 that had a minimum follow-up of 1 year.

RESULTS

One hundred and sixty-five patients were included. One hundred and seven subjects received antitubercular therapy (ATT) (n = 107/165; 64.9%) with all the patients receiving topical steroid therapy. Treatment failure was noted in 17 patients (n = 17/165; 10.3%), more frequently described in patients that received ATT (n = 13/107, 12.2%), than those that did not receive ATT (n = 4/58, 6.9%).

CONCLUSION

In this retrospective study, addition of ATT did not have any statistically significant impact on outcome in patients with TAU.

Collaborative Ocular Tuberculosis Study Consensus Guidelines on the Management of Tubercular Uveitis-Report 2: Guidelines for Initiating Antitubercular Therapy in Anterior Uveitis, Intermediate Uveitis, Panuveitis, and Retinal Vasculitis

TOPIC

The Collaborative Ocular Tuberculosis Study (COTS), supported by the International Ocular Inflammation Society, International Uveitis Study Group, and Foster Ocular Immunological Society, set up an international, expert-led consensus project to develop evidence- and experience-based guidelines for the management of tubercular uveitis (TBU).

CLINICAL RELEVANCE

The absence of international agreement on the use of antitubercular therapy (ATT) in patients with TBU contributes to a significant heterogeneity in the approach to the management of this condition.

METHODS

Consensus statements for the initiation of ATT in TBU were generated using a 2-step modified Delphi technique. In Delphi step 1, a smart web-based survey based on background evidence from published literature was prepared to collect the opinion of 81 international experts on the use of ATT in different clinical scenarios. The survey included 324 questions related to tubercular anterior uveitis (TAU), tubercular intermediate uveitis (TIU), tubercular panuveitis (TPU), and tubercular retinal vasculitis (TRV) administered by the experts, after which the COTS group met in November 2019 for a systematic and critical discussion of the statements in accordance with the second round of the modified Delphi process.

RESULTS

Forty-four consensus statements on the initiation of ATT in TAU, TIU, TPU, and TRV were obtained, based on ocular phenotypes suggestive of TBU and corroborative evidence of tuberculosis, provided by several combinations of immunologic and radiologic test results. Experts agreed on initiating ATT in recurrent TAU, TIU, TPU, and active TRV depending on the TB endemicity. In the presence of positive results for any 1 of the immunologic tests along with radiologic features suggestive of past evidence of tuberculosis infection. In patients with a first episode of TAU, consensus to initiate ATT was reached only if both immunologic and radiologic test results were positive.

DISCUSSION

The COTS consensus guidelines were generated based on the evidence from published literature, specialists' opinions, and logic construction to address the initiation of ATT in TBU. The guidelines also should inform public policy by adding specific types of TBU to the list of conditions that should be treated as tuberculosis.