Association between "sarcoidosis-like" disease and common variable immunodeficiency (CVI): a new CVI variant showing an activation of the immune system.

Background: Particular interest has been recently addressed to the association between a Granulomatous Sarcoidosis-like Disease (GSa-LD) and Common Variable Immunodeficiency (CVI).

Methods: The present paper discusses the clinical and immunopathological findings of the association between CVI and GSa-LD, based on four patients, whose clinical course was followed for about seven years. The lung involvement was studied by high resolution chest computed tomography scansion, classical parameters of lung function and diffusion lung carbon monoxide. All patients underwent bronchoalveolar lavage in order to exclude tuberculosis infection by culture analysis and polymerase chain reaction as well as to investigate the presence of active alveolitis.

Results: The clinical progression of patients were consistent with that reported in the literature confirming some distinct features in comparison with patients with CVI. In particular, patients with CVI/GSa-LD exhibited a reduced rate of respiratory infectious diseases, despite low levels of circulating immunoglobulins, and displayed a lower ability to develop bronchiectasies. Accordingly, the absolute number of circulating CD8+DR+, but not of CD4+DR+ T cells in CVI-GSa-LD patients were significantly lower than in the group of patients suffering from CVI alone. Moreover, patients with CVI/GSa-LD did not develop lung fibrosis (at least for the period of our follow-up) even though they show an active lymphocytic alveolitis in the bronchoalveolar lavage and displayed an higher degree of monocyte-macrophage activation.

Conclusions: A better definition of the molecular and cellular mechanisms involved in the development of systemic macrophage and T cell activation in immunodeficiency patients is required, in order to clarify the pathogenesis of sarcoidosis-like disease in CVI.