BACKGROUND. Мonoclonal gammopathy (MG) is not only the state preceding of hematological neoplasms, but also associated with non- hematological diseases, in particular damage of kidneys. Earlier diagnosis of MG represents an important area in treating patients with renal diseases associated with MG. THE AIM: To determine the frequency of MG among therapeutic and nephrological patients for optimization of methods of their diagnosis and treatment. PATIENTS AND METHODS: In common, 11392 patients were analyzed within 4 years (2013-2016). The standard clinical examination was conducted. Method of an electrophoresis of proteins of serum of blood and the 24-hour urine, method of immunofixation of proteins of serum and urine, and method of free light chains definition in serum (Freelite) were used for MG identification. RESULTS: MG is diagnosed in 174 of 11392 patients: 49 % of men and 51 % of women aged from 18 up to 85 years. MG was found 2.1 times more often in nephrological patient than in patients of therapeutic departments. Among patients of this group, AL-amyloidosis with kidney involvement was diagnosed in 41 %, cryoglobulinemic glomerulonephritis – in 18 %, chronic glomerulonephritis – in 35 %, also there was small number of patients with light chain disease and cast-nephropathy. 86 % of nephrological patients had less than 5 g/l of monoclonal protein that corresponds oligo secretory MG, and at 46 % from them – less than 1 g/l, other 10 % had MG of 5-10 g/l, and only in 4.42 % of patients MG more 10g/l was defined. CONCLUSION: We conclude that MG, especially oligo secretory form, play a significant role in pathogenesis of renal damage. It is important to apply sensitive methods – immunofixation of proteins and method «Freelite» for nephrological patients.
