[A case of renal Fanconi syndrome due to Bence Jones' protein K-type multiple myeloma].

A 60-year-old man, who had been treated for chronic kidney disease and chronic hepatitis B infection, was referred to our hospital following presentation with thoracic bone pain and exacerbation of proteinuria and hematu- ria. On admission, laboratory test results showed evidence of hypophosphatemia, glucosuria and elevated levels of both urinary NAG and 62MG.The patient was diagnosed with Fanconi syndrome based on findings indicating the presence of pan-aminoaciduria, elevated urinary excretion of uric acid and an increased phosphorus reabsorption rate.