Perforated meckel's diverticulitis and an ileal ulcer in rheumatoid arthritis: The pathogenic role of arterial thrombosis in these lesions

Gastrointestinal (GI) tract perforation is a serious complication in patients with rheumatoid arthritis (RA). This complication has been reported in the eras of both disease-modifying anti-rheumatic drugs (DMARDs) and biologics for RA. However,the etiopathogenesis of this condition has not been satisfactorily clarified to date. We experienced the case of an 83-year-old male treated with adalimumab,methotrexate(MTX)and prednisolone(PSL) who developed hematochezia. The operation demonstrated perforated Meckel's diverticulitis and an ileal ulcer; these complications occurred after the interruption of RA treatment for eight weeks. The pathology showed an artery with organized thrombi in the diverticular wall associated with recanalization and a fresh thrombotic arteriole beneath the ileal ulcer, although there was no evidence of arteriosclerosis, angiitis, amyloidosis or infection. The former site of arterial thrombosis was presumed to play an important role in the pathogenesis of perforated Meckel's diverticulitis and the ileal ulcer in this case. The onset of arterial thrombosis during or shortly after the discontinuation of biologic treatment has rarely been described. However, the potential for arterial thrombosis should thus be considered in patients receiving such treatment who present with perforation or ulcers of the GI tract.