Nowadays, upper gastrointestinal endoscopy is very commonly performed procedure as a diagnostic tool or therapeutic purpose. Although perforation rate during diagnostic evaluation has been reported as low about 0.03%, gastrointestinal perforation is a critical problem to the patients owing to significant morbidity and hospital stay. Therefore, all endoscopists should know the risk factors for the perforation and pay attention to avoid this complication. We experienced a case of 66 year-old-male with duodenal microperforation after endoscopic biopsy. During endoscopic examination, a submucosal mass was detected at duodenal second portion and endoscopic biopsy was performed. After this, he complained of severe abdominal pain during colonoscopy. Emergent simple abdomen and abdominal computed tomography revealed multiple free air in retroperitoneal space and duodenal perforation was suspicious. He was treated with primary closure and then recovered completely. Therefore, we report a case with microperforation after endoscopic duodenal biopsy.

Rapidly progressive glomerulonephritis(RPGN) is one of the most calamitous renal disease which is clinically characterized by sudden and relentless deterioration in renal function within weeks to months and associated with the pathologic finding of extensive extracapillary proliferation. Pauci-immune RPGN is mostly associated with anti neutrophil cytoplasmic antibody (ANCA) positive systemic vasculitis, but renal-limited RPGN may be found in part. We experienced a case of ANCA positive RPGN associated with polyclonal gammopathy without systemic symptoms. A 64-year-old woman was admitted with gross hematuria and azotemia. Laboratory findings revealed polyclonal gammopathy and severe anemia without definite cause, and she was diagnosed as C-ANCA positive crescentic glomerulonephritis without systemic vasculitis. She was treated with steroid pulse therapy and her renal function and anemia were progressively improved. We report herein a rare case of C-ANCA positive crescentic glomerulonephritis associated with polyclonal gammopathy and severe anemia with the review of literature.