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 [

Frequency and levels of autoantibodies in healthy adult Omanis

A previous pilot study showed a high frequency of anti-smooth muscle autoantibody in Omani blood donors and pregnant women. We conducted this larger-scale study to investigate the frequency and significance of several autoantibodies in healthy individuals from different regions of Oman. Sera obtained from 1537 healthy Omanis [1153 males and 384 females], ranging in age from 18 to 57 years, were tested for the presence of ten different autoantibodies using indirect immunofluorescence, haemagglutination and latex agglutination techniques. Low levels of autoantibodies were detected in 33.5%, whereas a few individuals [1.8%] showed high autoantibody titres. Anti-smooth muscle autoantibodies [ASMA] were the most prevalent [11%]. Anti-nuclear autoantibodies [ANA] were the second most prevalent [7.6%]. Anti-thyroid microsomal autoantibodies [ATMA] and anti-thyroglobulin autoantibodies [ATA] were present in 6.5% and 4.4% of individuals, respectively. The other autoantibodies were detected much less frequently: anti-parietal cells autoantibodies [APCA] were found in 1.6%, anti-brush border antibodies [ABBA] in 1.3%, anti-reticulin autoantibodies [ARA] in 1%, antimitochondrial antibodies [AMA] in 0.8%, antiglomerular basement membrane antibodies [AGBMA] in 0.7% and rheumatoid factor [RF] in 0.4%. The data indicate that autoantibodies are present in healthy Omani individuals, and therefore caution should be taken when interpreting laboratory results of patients suspected of having autoimmune disease