Ankylosing spondylitis is a common autoimmune disease caused by inflammatory rheumatic. The population morbidity ranging between 0.1 and 1.4% [6, 7]. There is accumulating evidence that patients with AS suffer from an increased ischemic stroke risk, in comparison with the general population [2–4]. Compared to patients without AS, the AS patients got a 2.20 times risk for ischemic stroke .
The reason why AS association a high risk of ischemic stroke remains unclear. But inflammatory processes seems played an important role in AS development. What’s more, the influence of inflammation in atherogenesis and plaque formation had been reported yet . Lange U et al. had found that, AS patients’ blood inflammatory markers were much higher compared with patients without AS, such as interleukin 6, tumor necrosis factor alpha, and C-reactive protein . In addition, in other literatures, AS patients were more likely to associated with early features of atherosclerosis, such as the thickness of intima media of the carotid arteries increased and flow-mediated dilatation of the brachial arteries impaired [10, 11]. Therefore, the atherogenesis and plaque formation caused by systemic inflammation may be the reason for higher risk of ischemic stroke in the AS patients.
Moyamoya disease is a cerebrovascular disease characterized by a progressive occlusion of the internal carotid artery or its terminal branches . The pathogenesis of moyamoya disease remains unclear. Suzuki and Takaku suspected that the autoimmune played an important role in MMD . Recently, more and more reports have showed the association between moyamoya and other autoimmune diseases, including Graves disease, Type 1 diabetes mellitus, systemic lupus erythematosus and Behcet’s disease [14, 15]. Review of the literatures reveals no report for MMD associate with AS. In our study, we think the autoimmune may play an important role in these two diseases. On the one hands, the autoimmune may be the reason for higher risk of ischemic stroke in the AS patients. On the other hands, although the mechanism of MMD was unclear, autoimmune probably was the most important mechanism for the pathogenesis of MMD. The patient in our study had typical moyamoya vessels and AS symptoms and diagnosed for both MMD and AS. The stenosis for this patient may cause by accelerated atherosclerosis which resulted from the same autoimmune mechanisms with the AS. Therefore, MRA, CTA or DSA needs to be done if AS patients suffer cerebrovascular events.
According to the guidelines of AS management issued by international experts, NSAIDs, including selective inhibitors of cyclooxygenase 2, are the first-line drug for the pain and stiffness treatment . In our patient, he received NSAID treatment about three months, low back pain and morning back stiffness got some relief, whereas TIA was more frequency. Therefore, he underwent a right EDAS and had no further TIAs. EDAS may have a role for prevention of TIA in AS patients with moyamoya disease. However, longer follow-up should be taken to evaluate the long-term effects of EDAS in patient with MMD and AS.