The immunoglobulin and complement levels in the active pulmonary sarcoidosis.

Background And Aim: In sarcoidosis patients the circulating immune complex levels are raised with the activation of the disease but their diagnostic role is not clear. These circulating immune complexes contain complement and immunoglobulins (Ig). Complement and immunoglobulins are mostly accumulated in active sarcoid lesions and in circulating immune complexes. Thus complement and Ig levels in circulation will be reduced in active sarcoidosis patients due to their higher deposition in sarcoid lesions. We tried to make an estimation about the activity of the disease through measuring the IgG, IgA, and IgM and complement (C3-C4) levels in the serum.

Methods: Thirty-two (8 men) sarcoidosis patients (with their symptoms, chest x-ray graphies, bronchioalveolar lavage findings and the other related WASOG criteria) were divided into two groups as active and inactive cases. We measured with the immunodiffusion method the immunoglobulin and complement parameters of these two groups and compared them with each other.

Results: Compared to the active group the IgG and IgA in serum were significantly higher in the inactive group (p < 0.001, p=0.07 ). Although statistically not significant the IgM and C3, C4 levels were higher too in the inactive group.

Conclusions: The IgG, IgA, IgM and the complement levels in serum are higher in the inactive group. We think that these findings might be useful for the follow up of the disorder's activity in sarcoidosis patients. In order to prove these finding studies with larger volume are needed.