Monocyte disorder causing cellular immunodeficiency: a family study

We report a familial type of monocyte dysfunction not recognized previously. This disorder wasobserved in a young adult man with a long clinical history of recurrent, sell‐limited episodes ofcryptogenic fever accompanied by digestive and respiratory symptoms and repeated oral and skininfections. Lectin‐induced lymphocyte transformation was reduced and skin tests revealed anergy totuberculin and candidin. Monocytes from this patient exhibited markedly diminished expression ofcytoskeletal vimentin intermediate filaments. HLA‐DR antigens and immunological receptors forIgG Fc and C3b. These abnormal monocytes demonstrated impaired phagocytosis and reducedaccessory cell function on PHA‐mediated lymphoeyte activation. Release of soluble lymphocyte‐activating factors by these cells was found to be defective. Lymphocytes from the patient respondedappropriately to lectin in the presence of normal monocytes. Two family members of the probandpresented similar monocyte defects although they only manifested minor clinical symptoms. Thissyndrome underlines the interest of testing monoeyte markers and function in subjects with clinicalmanifestations of immunodeficiency.