Monocyte disorder causing cellular immunodeficiency: a family study.

We report a familial type of monocyte dysfunction not recognized previously. This disorder was observed in a young adult man with a long clinical history of recurrent, self-limited episodes of cryptogenic fever accompanied by digestive and respiratory symptoms and repeated oral and skin infections. Lectin-induced lymphocyte transformation was reduced and skin tests revealed anergy to tuberculin and candidin. Monocytes from this patient exhibited markedly diminished expression of cytoskeletal vimentin intermediate filaments, HLA-DR antigens and immunological receptors for IgG Fc and C3b. These abnormal monocytes demonstrated impaired phagocytosis and reduced accessory cell function on PHA-mediated lymphocyte activation. Release of soluble lymphocyte-activating factors by these cells was found to be defective. Lymphocytes from the patient responded appropriately to lectin in the presence of normal monocytes. Two family members of the proband presented similar monocyte defects although they only manifested minor clinical symptoms. This syndrome underlines the interest of testing monocyte markers and function in subjects with clinical manifestations of immunodeficiency.