<p>Analysis of M-components is an important part of the diagnosis of monoclonal gammopathies and for the evaluation of disease response during treatment. In this project, two widely used electrophoresis methods and their corresponding immunotyping method were compared to evaluate the sensitivity of each method for the detection of small M-components. The project included 30 plasma samples from patients with identified M-components; 10 samples containing each IgG, IgA and IgM, respectively. All samples were diluted with normal EDTA plasma to achieve M-components of 5,00g/L. The samples were then serially diluted to achieve M-component concentrations of; 5,00, 2,50, 1,25, 0,63, 0,31 and 0,16g/L. All 180 samples were analysed with agarose gel electrophoresis and capillary electrophoresis. The dilutions above and below the detection level of each method were then analysed with immunofixation and immunosubtraction. The results showed good agreement between agarose gel electrophoresis and capillary electrophoresis in the highest concentrations of IgG and IgM. With agarose gel electrophoresis, IgA was detected in the same location as transferrin and the lowest concentration detected were therefore 1,25g/L. Besides the samples containing IgG, immunofixation was the most sensitive method.</p>

Analysis of M-components is an important part of the diagnosis of monoclonal gammopathies and for the evaluation of disease response during treatment. In this project, two widely used electrophoresis methods and their corresponding immunotyping method were compared to evaluate the sensitivity of each method for the detection of small M-components. The project included 30 plasma samples from patients with identified M-components; 10 samples containing each IgG, IgA and IgM, respectively. All samples were diluted with normal EDTA plasma to achieve M-components of 5,00g/L. The samples were then serially diluted to achieve M-component concentrations of; 5,00, 2,50, 1,25, 0,63, 0,31 and 0,16g/L. All 180 samples were analysed with agarose gel electrophoresis and capillary electrophoresis. The dilutions above and below the detection level of each method were then analysed with immunofixation and immunosubtraction. The results showed good agreement between agarose gel electrophoresis and capillary electrophoresis in the highest concentrations of IgG and IgM. With agarose gel electrophoresis, IgA was detected in the same location as transferrin and the lowest concentration detected were therefore 1,25g/L. Besides the samples containing IgG, immunofixation was the most sensitive method.

Multiple myeloma (MM) is an incurable progressive hematologic malignancy with heterogeneous evolution. It is a disease characterized by abnormal clonal proliferation of plasma cells in the bone marrow producing monoclonal immunoglobulins and causing a number of organ dysfunctions. Most patients relapse after treatment. Therefore, the use of methods of analysis of serum and urinary samples in order to detect as early as possible the presence of monoclonal immunoglobulins, before the occurrence of relapses, may aid in the treatment of patients with MM, improving its quality and prolonging survival. In this study we compared the effectiveness of the techniques of immunofixation (IF) and electrophoresis (EP) in the detection of MM relapses. For this, 52 patients under treatment in the University Hospital of Santa Maria (HUSM) were monitored, being detected the relapse of the disease in nine of these patients. A retrospective analysis of serum proteins of the nine patients, between January 2012 and July 2014, showed that IF was more effective than EP in early detection of relapse, regardless of the present class of immunoglobulins. The precocity of IF in relation to EP in detecting MM relapses in the nine patients studied, ranged from 2.0 to 18.8 months, with a mean of 6.6 months. Thus, we suggest the implementation of IF in the Clinical Analysis Laboratory (CAL) of HUSM to help onco-hematology physicians in the diagnosis and supportive care for patients with MM. / O mieloma múltiplo (MM) é uma neoplasia hematológica progressiva, com evolução heterogênea e ainda incurável. É uma doença caracterizada pela proliferação clonal anormal de plasmócitos na medula óssea produzindo imunoglobulinas monoclonais e ocasionando uma série de disfunções orgânicas. A maioria dos pacientes recidivam após o tratamento. Portanto, a utilização de métodos de análise de amostras séricas e urinárias, que permitam detectar o mais precocemente possível a presença de imunoglobulinas monoclonais, antes da ocorrência das recidivas, pode auxiliar no tratamento de pacientes com MM, melhorando a qualidade e ampliando o tempo de sobrevida dos mesmos. No presente estudo foram comparadas as técnicas de imunofixação (IF) e eletroforese (EF) quanto a sua eficácia na detecção das recidivas do MM. Para isso, foram monitorados 52 pacientes em tratamento junto ao Hospital Universitário de Santa Maria (HUSM), sendo detectada a recidiva da doença em nove destes pacientes. A análise retrospectiva de proteínas séricas dos nove pacientes, no período entre janeiro de 2012 e julho de 2014, mostrou que a IF foi mais eficaz do que a EF em detectar precocemente as recidivas, independentemente da classe de imunoglobulinas presente. Nos nove pacientes recidivados, a precocidade da IF, em relação à EF, na detecção das recidivas do MM variou de 2,0 a 18,8 meses, com um tempo médio de 6,6 meses.