Reference ranges for serum immunoglobulin A, G and M in the adult population from the South of Oman

Data on the normal levels of serum immunoglobulins in the south of Oman is lacking. This region of Oman is unique in its climate and environment compared to all other regions of Oman and the Gulf countries. We have conducted this study to determine the reference levels of serum immunoglobulin G, M and A in an adult healthy group of individuals from the south of Oman. Serum samples were collected from 489 healthy Omani individuals, 389 males and 100 females, from the southern area of Oman [Dhofar]. The age range of the males and females were 18 to 54 and 19 to 48 years, with an average of 30 and 24 years, respectively. Serum lgG, IgM and IgA levels were measured using a rate nephelometer. The mean serum levels of lgG, IgM and IgA were 12.88 g/L, 1.01 g/L and 2.64g/L, respectively. The lower and upper limits for the normal serum levels of IgG, IgM and IgA were determined as 8.52-17.45g/L; 0.374-2.05g/L and 1.23-4.77g/L, respectively. No significant difference in the mean serum levels was observed between the two sexes for lgG. However, IgM and IgA levels were significantly higher in the female group [P<0.001]. Young individuals with age below 20 years have significantly low levels of IgA [P<0.01] as compared to those above this age. The normal levels of the serum immunoglobulin G, M, and A were established for this Omani group. Our results confirmed the significant difference in IgM concentration between adult male and female individuals, with females having higher levels than males. Further, the results showed the occurrence of low levels IgA in young Dhofari individuals [