Reports of three cases with the initial presentation of mesenteric vasculitis in children with system lupus erythematous.

We reviewed three cases of systemic lupus erythematosus (SLE) in children with mesenteric vasculitis (LMV) as initial presentation and analysed their clinical characteristics to improve the understanding of this disease. Three patients with SLE were admitted to our hospital and initially presented with gastrointestinal symptoms. We retrospectively analysed their clinical data, including clinical presentations, laboratory results, images and short- and long-term treatment outcomes. (1) All three children were school-age girls. The patients were presented to our hospital with vomiting and abdominal pain as initial symptoms. The patients also had urinary symptoms, including proteinuria in three cases, ureteropelvic dilatation in two cases and hydronephrosis in one case. (2) The patients had various positive autoantibodies and a low complement level. Two of the patients had blood system involvement, and one had central nervous system symptoms. (3) All of the patients had active SLE (SLEDAI-2K score ≥ 5 points and moderate to severe degree 10-24). (4) Abdominal CT scans with contrast showed the 'target sign' of the intestinal wall in case 1, a slightly thickened intestinal wall and blurry mesentery in case 2, and the 'comb sign' of the margin mesenteric blood vessels in case 3. (5) All three patients responded promptly to steroid therapy. The patients' symptoms improved rapidly after treatment. LMV is a rare SLE complication. The lack of comprehensive understanding of LMV's clinical presentation makes it considerably challenging to diagnose. LMV is also a serious complication of SLE that is often accompanied by concurrent damage to other organs. LMV often occurs with active SLE but responds rapidly to glucocorticoid therapy. Therefore, in order to make early diagnosis and treatment, we suggest checking autoantibodies and abdominal CT scans with contrast when children present with gastrointestinal symptoms and the involvement of other organs, especially the urinary system.