Duodenojejunal inflammation causing chronic vomiting in adult-onset Still's disease

Adult-onset Still's disease (AOSD) is a rare systemic autoinflammatory disease with a broad spectrum of clinical manifestations including fever, skin rash, arthralgia and neutrophilic leucocytosis. Small bowel inflammation in AOSD has been reported in association with Crohn's disease, coeliac disease and chronic intestinal pseudo-obstruction. We have here reported the first-time case of AOSD with small bowel involvement, presenting with chronic vomiting. Fluorodeoxyglucose total-body positron emission tomography/CT showed high uptake of the duodenum and first jejunal loop. Faecal calprotectin increased. Duodenal histology revealed neutrophilic infiltrate among duodenal enterocytes and severe chronic lymphoplasmacellular infiltrate of the lamina propria. Vomiting disappeared when duodenojejunal inflammation was controlled by immunomodulatory treatments for AOSD, suggesting a possible causal relation between duodenojejunal inflammation and the symptom.