病例:男,7岁4个月。自2岁起反复发作肉眼血尿,每因呼吸道感染后加重,曾被多家医院诊断为急性肾炎、良性血尿和IgA肾病。既往有支气管哮喘史,其父亲及姑姑在学龄儿童期患过急性肾炎,母亲患过肾盂肾炎,均已治愈。体检:T、P、R正常,BP13/9kPa,体重18.5kg,发育营养不佳,咽充血,扁桃体Ⅱ度大,心肺无异常,肾区无叩击痛。血常规正常,尿常规(电脑测 Case: male, 7 years and 4 months. Since the age of 2 repeated episodes of gross hematuria, increased after each respiratory tract infection, has been diagnosed in many hospitals as acute nephritis, benign hematuria and IgA nephropathy. Past history of bronchial asthma, his father and aunt suffered from acute nephritis in school-age children, mother had pyelonephritis, have been cured. Physical examination: T, P, R normal, BP13 / 9kPa, weight 18.5kg, poorly developed nutrition, pharyngeal congestion, tonsil Ⅱ degree, no abnormal heart and lungs, no perineal pain in the kidney area. Normal blood, urine routine (computer test