Electrophoretical distribution of serum monoclonal protein and underlying causes. Data from a referral center in Mexico

Abstract

Background: Monoclonal gammopathies are a group of disorders characterized by an overproduction of monoclonal immunoglobulin. Detection and quantification of monoclonal components using serum protein electrophoresis (SPE) for screening is the initial step in the evaluation of monoclonal gammopathies. This study aimed to describe the electrophoretic patterns of Hispanic patients with suspected monoclonal gammopathy in our hematological disease referral center. Material and methods: All SPE tests performed between January 2013 and November 2017 at the Hematology Service Laboratory in the "Dr. José Eleuterio González" University Hospital were collected in which monoclonal gammopathy was suspected. Age, gender, and diagnosis, when available, were recorded. We described the immunoelectrophoretic patterns by SPE according to the type of gammopathy. Results: A total of 1461 SPE results were collected. Sixty-four percent of the patients had an abnormal electrophoretic pattern, 19.5% a polyclonal gammopathy, and 44.7% exhibited at least one monoclonal component (monoclonal gammopathy). The isotype most found was IgG in 108 (52.9%), followed by IgA in 40 (19.6%) serum samples, and kappa was the most frequently involved light chain. In 86% of patients, we were able to establish a definitive diagnosis. The most common monoclonal gammopathy was multiple myeloma in 89%, and only one case of monoclonal gammopathy of undetermined significance was diagnosed. Conclusion: Our group of patients exhibits different electrophoretic patterns from previous reports. Multiple myeloma is the most common monoclonal gammopathy, and monoclonal gammopathy of undetermined significance possibly goes underdiagnosed.

Seek and ye shall find: monoclonal gammopathy of undetermined significance

“…Furthermore, in another previous work, we published in this journal 4 , we reported that MGUS was related to only 0.5% of all cases of MG and found that in our country, this entity seems to be underdiagnosed or not as highly identified as in higher-income countries. However, after sampling the healthy subjects, we observed that the prevalence of MGUS (4%) could pair up with international reports.…”

“…At present, the Iceland Screens, Treats, or Prevents Multiple Myeloma (iStopMM) study (the first nationwide population-based Medicina Universitaria registry that targets screening MGUS and performing randomized clinical trials of interventions for preventing malignant progression) has recently found that the age-and sex-standardized prevalence of MGUS is 5% in individuals over 50 years, which is higher than previous reports for this age group, and confirmed that there is higher prevalence associated with increasing age and male individuals. In the following years, we expect to understand the implications of the early screening in the general population and determine the effects of early treating MG malignancies or if they can be prevented 4 . The optimal screening interval for these individuals has not been established and may depend on individual factors (Fig.…”