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Introduction Serum measurement of free light chain (FLC) has been used for diagnosis and monitoring of patients with plasma cell dyscrasias. The aim of the study was to determine the prognostic value of FLC in multiple myeloma (MM) and to identify other independent prognostic factors of MM. Methods Biochemical and clinical data of 59 MM patients (age, Ig isotype, M protein, haemoglobin, platelet, serum calcium, creatinine, albumin, plasma cell infiltration and bone lesions) were retrieved. FLC and β 2 microglobulin (β 2 M) were measured in the sera collected at the time of diagnosis. Survival time was calculated by the Kaplan–Meier method and Cox regression analysis was done to analyse the prognostic indicators. Results The majority of MM patients were of IgG isotype (74.6%). Fifty-seven of 59 (97%) MM patients had abnormal FLC ratio. Median survival time was 46 months. Cox univariate analysis revealed that albumin, calcium, creatinine, FLC ratio, international staging system, and β 2 M were significantly associated with survival ( p = 0.02, 0.002, 0.045, 0.04, 0.045, 0.013, respectively). Cox multivariate analysis revealed that calcium, β 2 M and FLC ratio were independent prognostic predictive factors ( p = 0.022. 0.006 and 0.011, respectively). Conclusions Serum FLC ratio is an independent prognostic indicator for MM in addition to calcium and β 2 M.

Glucose 6-phosphate dehydrogenase (G6PD) deficiency is a X-linked disorder causing neonatal jaundice and haemolysis on oxidative stress. We compared the currently used fluorescent spot test (FST) against a quantitative assay (OSMMR2000-D) and molecular testing methods for screening and identification of G6PD deficient neonates. A total of 1371 cord blood samples were tested using the semiquantitative FST and quantitative G6PD assay. Positive FST samples were subjected to allelic discrimination assays for G6PD Viangchan, Mediterranean, Canton and Kaiping, which encompass over 75% of the G6PD mutations detected in our population. Positive FST results were seen in 86 (6.3%) of the samples tested. Mean G6PD level using the quantitative assay was 15.3 U/g haemoglobin (Hgb) with 60% and 20% enzyme activity 9.2 and 3.1 U/g Hgb, respectively. Twenty-one of the 86 samples detected as positive by FST had activity above 9.2 U/g Hgb, 10 of which were identified as harbouring one of the four mutations tested. The quantitative assay used in this study, using cord blood samples may cause false negative results if limits are established as proposed. We propose that the FST remains an effective screening tool for G6PD deficiency and can be supplemented by rapid real time molecular identification methods for confirmation.