The clinical spectrum of the immunocompromised host: a pathology engineered by progress

The term "immunocompromised host" (ICH) embraces patients with a remarkably heterogeneous array of disease forms whose common feature is an immunologic deficiency of varying gravity and extent. From the clinical standpoint, too, they display a heterogeneous spectrum, ranging from virtually symptom-free pictures through all the intermediate stages to the appearance of typical manifestations including: a) high susceptibility to recurrent infection by opportunistic germs; b) frequent though not always clinically significant autoimmune phenomena; c) the occasional appearance of some tumors (mostly Kaposi's sarcoma and hemolymphopoietic system neoplasias), also referred to as "opportunistic" by analogy with opportunistic infections. The existence of a variety of modern treatments (organ and bone marrow transplantation, aggressive combination chemotherapy and/or radiotherapy of tumors, prolonged administration of immunodepressants in a number of immune-mediated disease conditions, etc.) that prolong survival in patients with chronic immunodeficiency states previously responsible for early death has led to a new "pathology engineered by progress".