A case of monoclonal gammopathy of renal significance

Monoclonal gammopathy of renal significance (MGRS) is a condition defined by the presence of a small-B cell clone causing a renal disease trough deposition in renal tissues of the monoclonal component (MC) secreted by the B cells. Since MGRS is associated with several types of renal diseases, characterization of renal damage caused by protein deposition is important to define the correct diagnosis as well as the identification of the MC. Adult Fanconi Syndrome (FS) is characterized by the presence of a MC and damage in the proximal tubule with impaired small molecules transport. We report the case of a 32 years old man with moderate kidney failure, normoglycemic glycosuria and hypouricemia. Further investigations revealed hypophosphoremia and phosphaturia; an IgGek MC was detected by immunofixation. The kidney biopsy confirmed FS suspect. This case underlines that the results of the biochemical analysis carried on for the diagnosis of FS, need to be confirmed by histopathologic analysis.