X-ray films of the SI joints are the gold standard for diagnosis of AS (Fig. 19.1), with radiographic evidence of sacroiliitis required for diagnosis based on the modified New York criteria. Figure 19.2 demonstrates the “bamboo spine” with fusion of multiple vertebral bodies. However, plain films can significantly lag behind symptoms [29] and consequently other imaging modalities have utilized in recent years [30]. Recent studies have shown that MRI has the highest sensitivity and specificity of all imaging techniques for SI joint inflammation [31], with T1 with gadolinium or fat-suppressed T2 images being the most effective in visualization of inflammatory features.

Acute anterior uveitis (AAU) is the most common ophthalmologic manifestation of AS. Presenting symptoms include pain, redness, photophobia, and blurred vision. Exam findings include ciliary flush, conjunctival hyperemia, nongranulomatous keratic precipitates, anterior chamber cell/flare, and posterior synechiae. HLA-B27 AAU is frequently associated with formation of a hypopyon. The majority of cases are isolated to the anterior chamber, but posterior segment involvement has been reported in 17.4 % of patients with HLA-B27 uveitis, most commonly presenting with vitritis (93.1 %), papillitis (82.7 %), retinal vasculitis (24.1 %), and pars plana exudates (6.8 %) [32].

Scleritis is also associated with AS, in 0.34–0.93 % of patients with AS [33]. Scleritis typically presents after many years of active AS and tends to present most frequently as mild–moderate diffuse anterior scleritis [34].

Acute treatment of AAU is typically with a course of topical corticosteroids and cycloplegic eyedrops, though more severe cases may require additional agents. Topical Prednisolone 1 % has been used for decades with excellent efficacy. Recently, topical Difluprednate 0.05 % (Durezol) has been shown to be at least as effective at @4x/day dosing as topical Prednisolone 1 % at 8x/day dosing [35]. Cycloplegic agents including Atropine 1 %, Homatropine 5 %, Isopto Hyoscine 0.25 %, and Cyclopentolate 1 % are effective in treating posterior synechiae, reducing pain and photosensitivity.

Periocular steroid injections of triamcinolone (40 mg/1 mL), administered either into sub-Tenon’s space or trans-septal into the peribulbar space are effective for more severe flares that fail to respond to topical therapy. A course of oral Prednisone can be employed for patients with severe disease, particularly those with posterior segment involvement.

Various non-pharmacologic therapeutic options have been attempted in AS, including exercise, massage, and hydrotherapy, which may be effective for early disease or as an adjunct to pharmacologic therapy in those predominantly with joint manifestations.

NSAIDs have been the first-line therapy for the treatment of AS since their introduction in the 1950s, with superior outcomes with the use of COX-2 inhibitors [36]. Superior outcomes have also been noted with continuous, rather than intermittent, use of NSAIDs in AS [37]. Similarly, NSAIDs have been shown to be effective in the treatment of AAU, reducing the average number of flares from 2.84 to 0.53 per patient over a 2 year period in a recent study [38].

For patients with chronic or frequently recurrent AAU, steroid-sparing agents have been recommended by numerous expert panels [39] as the standard of care. Methotrexate has shown excellent efficacy in the treatment of recurrent uveitis [40] and is often employed as a steroid-sparing entity in this disease. However, the results for MTX with AS have been generally disappointing, with a recent Cochrane review stating there is not enough evidence to support any benefit of MTX in the treatment of AS [41]. This report was focused on arthritic manifestations and joint destruction; ocular manifestations of ankylosing spondylitis were not assessed by this review. Sulfasalazine has also been evaluated for the treatment of AS and found to be ineffective in a recent meta-analysis [42].

Biologic therapies have shown excellent promise in both the treatment of AS and uveitis. TNF-alpha is expressed in high amounts at the site of inflammation in AS [43] and TNF-alpha inhibitors have shown efficacy in the treatment of AS. These include Adalimumab (Humira), Etanercept (Enbrel), Infliximab (Remicade), Golimumab (Simponi), and Certolizumab Pegol (Cimzia). All five of these medications have been approved by the FDA for treatment of ankylosing spondylitis and are frequently used in patients whose disease has progressed despite NSAID therapy.

However, these medications have shown variable results in the treatment of uveitis. Etanercept, in particular, has been shown to be ineffective in the treatment of uveitis [44] and has been suggested to even induce uveitis in some patients [45]. Infliximab, conversely, has been demonstrated to be effective for several forms of uveitis [46], including a large retrospective review of patients with birdshot retinochoroidopathy [47]. Adalimumab received FDA approval in July 2016 for the treatment of noninfectious intermediate, posterior and panuveitis, the first biologic to be approved for uveitis. This was the result of a multinational phase 3 trial that demonstrated lower risk of uveitic flares in patients treated with Adalimumab [48]. Golimumab and Certolizumab Pegol have more limited data, with a small case series supporting the use of Golimumab in JIA-associated uveitis [49].

In patients with both uveitis and arthritis from ankylosing spondylitis, selection of an appropriate chronic anti-inflammatory therapy can be effective in ameliorating disease manifestations. Often this approach requires coordination between the ophthalmologist and rheumatologist. Based on available data, NSAIDs and TNF-alpha inhibitors are drug classes which have excellent evidence of efficacy and safety for both uveitis and arthritis associated with AS.