Abstract:To explore the value of fructosamine (FMN) and albumin (ALB) / globulin (GLB) (A/G) ratio in the diagnosis of immunoglobulin A (IgA) type multiple myeloma (MM). Methods Sixty-four patients with IgA type MM (IgA type group), 70 patients with immunoglobulin G type MM (IgG type group), 7 patients with immunoglobulin M type MM (IgM type group), 60 patients with autoimmune disease (AID group) and 50 people with healthy examination (control group) were selected. FMN was analyzed by nitro-blue-tetrazolium colorimetric method. Total protein (TP) was analyzed by biuret method. ALB was analyzed by bromocresol green method and then A/G was calculated. All selected cases were excluded from diabetes. The correlations between FMN value and laboratory indexes were analyzed. The receiver operating characteristic (ROC) curve was used to analyze the value of the indexes in the diagnosis of IgA type MM. Results FMN level of the IgA type group was obviously higher than those of other groups (p < 0.05). The results of linear correlation analysis indicated that serum FMN was positively correlated with TP and GLB in the IgA type group (r =0.831 and 0.869,p = 0.000), and negatively correlated with ALB and A/G (r = -0.733 and -0.716, p= 0.000).Areas under the ROC curves of FMN, A/G single detection and joint detection for the diagnosis of IgA type MM were 0.976, 0.207 and 0.980, respectively. The sensitivity and specificity (98.4% and 74.9%) of FMN single detection were higher than those of A/G single detection (95.3% and 44.4%). Using FMN and A/G joint detection, the specificity (90.9%) increased in the clinical diagnosis of IgA type MM without decreasing the sensitivity (95.3%). Conclusions FMN can be one of the reference indexes for diagnosis of IgA type MM.Joint detection of FMN and A/G can improve specificity while still has high sensitivity. They are appropriate for screening of IgA type MM.