14岁男性患者,起病前3周出现上呼吸道感染,以急进性肾炎综合征(肉眼血尿、肾功能不全)入院,实验室检查发现补体C3降低、抗链球菌溶血素“O”升高,抗中性粒细胞胞质抗体和抗肾小球基膜抗体阴性;肾活检组织学改变为Ⅱ型新月体肾炎,电镜下上皮侧见“驼峰”样电子致密物。考虑急性链球菌感染后肾小球肾炎。 14-year-old male patient, upper respiratory tract infection occurred 3 weeks before onset, with acute nephritic syndrome (gross hematuria, renal insufficiency) admission, laboratory tests found that complement C3 decreased anti-streptolysin High, anti-neutrophil cytoplasmic antibody and anti-glomerular basement membrane antibody negative; renal biopsy histological changes to type II crescentic nephritis, electron microscopy see the “hump ” -like electron dense material. Consider glomerulonephritis after acute streptococcal infection.