HLA-B27 test is generally positive in spondyloarthritis (SpA) and ankylosing spondylitis (AS). Several anomalous laboratory test results are frequently found in HLA-B27-positive patients. In this study, we intended to evaluate two groups of HLA-B27 positive patients- one group belonging to the 13-40 years age group and another group belonging to the 41-71 years age group. The rationale of this partition was based on the age when AS first emerged and the age when the disease was set up for quite a few years respectively. We anticipate alterations of several familiar laboratory test outcomes between these two groups. After our analysis, we found that in the upper age group, neutrophil percentage and CRP levels were significantly increased, while lymphocyte percentage was significantly decreased. ESR levels also decreased but were not statistically significant. There was practically no change in average PCR ct values, haemoglobin levels, total count of leucocytes, uric acid, creatinine, SGPT, or HbA1C levels between the two groups. The plausible explanations behind these changes are discussed.