Urinary beta 2- and alpha 1-microglobulin levels in normal subjects in Singapore

Differing normal values for urinary beta 2-microglobulin have been reported for different countries. In this study, we have attempted to establish the urinary beta 2- and alpha 1-microglobulin levels of apparently healthy subjects in Singapore. Urine samples collected from 271 subjects were analysed. The subjects ranged from 19 to 62 years old, with a mean age of 36.8 years. The majority (84.5%) were non-smokers. Urine samples with a pH level < 5.5 were excluded from the analysis. The urinary beta 2- and alpha 1-microglobulin values followed log normal distributions. Their 95th percentiles were 288 micrograms/g creatinine and 7.35 mg/g creatinine, respectively. Statistically significant differences were found between sexes and ethnic groups for urinary beta 2-microglobulin values. Both alpha 1- and beta 2-microglobulin values increased significantly with age. Smokers had significantly higher urinary alpha 1-microglobulin values.