Particular attention has been recently dedicated to the development of a sarcoidosis-like form in patients with common variable immunodeficiency (CVI). In sarcoidosis a 5-fold increase in the number of cells in the bronchoalveolar lavage compared with normal controls has been described and the predominance of CD4+ T cells is a common feature. In contrast to patients affected by sarcoidosis or CVI, patients with co-existence of the two diseases had a more favorable prognosis, as progressive pulmonary fibrosis occurred only in a few cases even when persistent alveolar lymphocytosis was present. Moreover, patients presenting with concomitant sarcoidosis and CVI, showed a lower rate of respiratory infections and of the evolution towards bronchiectasies in comparison with patients affected by CVI alone. The clinical evolution observed in our patients was similar with that reported in other studies and confirms their clinical features. One may speculate that the increase in the number of macrophages and T lymphocytes, as suggested by the increased cellularity in the bronchoalveolar lavage of these patients, can produce a peculiar microenvironment characterized by high levels of soluble factors (cytokines). In turn, the latter could be responsible for a more efficacious effector phase of the immune response. This may explain the reduced rate of infectious diseases and consequently of bronchiectasies observed in CVI patients.