Grisel syndrome in pediatric rheumatic diseases as a rarely recognized complication: case-based review.

Grisel syndrome (GS) is a rare, non-traumatic atlantoaxial rotatory subluxation that predominantly affects children and can lead to severe neurological complications such as quadriplegia, radiculopathy, and respiratory arrest. It typically occurs following upper respiratory tract infections or head and neck surgery. Although GS associated with systemic inflammatory diseases such as Kawasaki disease (KD) and acute rheumatic fever (ARF) has been reported, these cases usually involve an underlying infectious trigger. In contrast, we report two cases of GS that developed without any infectious or surgical triggers: one associated with juvenile idiopathic arthritis (JIA) and the other with familial Mediterranean fever (FMF). These cases highlight that systemic inflammation alone may be sufficient to induce atlantoaxial instability, emphasizing the need for clinicians to consider GS in patients with systemic inflammatory conditions presenting with neck pain or torticollis, even in the absence of infection or surgical history. Early recognition and prompt management are crucial for preventing serious neurological sequelae. Due to the limited number of GS cases reported in association with rheumatologic diseases, this report also includes a review of the literature to provide a broader perspective on this rare but serious complication.