Intestinal Pseudo-Obstruction with Life-Threatening Hypokalaemia in a Patient with Adult-Onset Still's Disease.

Adult-onset Still's disease (AOSD) is a rare autoinflammatory disorder that can lead to a cytokine storm, causing a range of symptoms. Acute intestinal pseudo-obstruction is another rare condition that results in intestinal obstruction without anatomical cause. Although the two conditions are rarely reported together, we present the case of a 62-year-old male who developed acute intestinal pseudo-obstruction in the context of an AOSD flare. This led to severe hypokalaemia and a critical condition. Other symptoms included a high-spiking fever lasting for weeks, polyarthralgias and a typical salmon-coloured rash. After ruling out other potential causes, the patient was diagnosed with AOSD. Our findings suggest that the cytokine storm associated with this disease triggered the acute intestinal pseudo-obstruction and life-threatening hypokalaemia, establishing a causal relationship. Only four other cases of AOSD complicated by intestinal pseudo-obstruction have been reported, and this is the first to present with life-threatening hypokalaemia. This case serves as a crucial reminder that, despite being a diagnosis of exclusion, Still's disease should be considered as a potential cause of intestinal pseudo-obstruction, as prompt recognition and treatment of the underlying cause is crucial in managing this potentially life-threatening condition. LEARNING POINTS: Acute intestinal pseudo-obstruction is one of the systemic complications that can occur in autoinflammatory diseases such as AOSD, although it has rarely been described.If AOSD presents with abdominal presentation, such as acute intestinal pseudo-obstruction, then amyloidosis should always be carefully considered.