Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.
Clin Mol Hepatol. 2018 Sep;24(3):339-344. doi: 10.3350/cmh.2017.0009. Epub 2017 Sep 1.
Fanconi syndrome is a dysfunction of the proximal renal tubules that results in impaired reabsorption and increased urinary loss of phosphate and other solutes. The pathophysiology of drug-induced Fanconi syndrome is unclear. Here we report the case of a 36-year-old woman who presented with pain in multiple bones and proteinuria. She had a 7-year history of taking adefovir at 10 mg/day for chronic hepatitis B. Three years previously she had received surgery for a nontraumatic right femur neck fracture, after which she continued to complain of pain in multiple bones, and proteinuria, glycosuria, and phosphaturia were noted. The findings of a light-microscope examination of a renal biopsy sample were normal, but mitochondrial damage of the proximal tubules was evident in electron microscopy. Western blot analysis revealed that the level of serum fibroblast growth factor 23 (FGF23) was lower than in normal controls. After 2 months of treatment, hypophosphatemia and proximal tubular dysfunction were reversed, and serum FGF23 had normalized. This case suggests that direct mitochondrial damage in proximal tubules can cause drug-induced Fanconi syndrome associated with osteomalacia.
范可尼综合征是近端肾小管功能障碍，导致磷酸盐和其他溶质重吸收减少和尿丢失增加。药物诱导的范可尼综合征的病理生理学尚不清楚。我们在此报告 1 例 36 岁女性，因多发性骨痛和蛋白尿就诊。她患有慢性乙型肝炎，7 年前每天服用阿德福韦酯 10 mg。3 年前，她因非外伤性右股骨颈骨折接受了手术，此后她继续抱怨多处骨痛，并出现蛋白尿、糖尿和磷酸盐尿。肾活检样本的光镜检查结果正常，但电镜下可见近端肾小管的线粒体损伤。Western blot 分析显示血清成纤维细胞生长因子 23（FGF23）水平低于正常对照。经过 2 个月的治疗，低磷血症和近端肾小管功能障碍得到逆转，血清 FGF23 恢复正常。本病例提示直接的近端肾小管线粒体损伤可引起与骨软化症相关的药物诱导的范可尼综合征。
