ABSTRACT
Primary immunodeficiency disorders (PIDs) comprise many
diseases caused by genetic defects affecting the immune
system. Over the last 25 years, 214 diseases have been
identified with more than 120 genetic defects identified to
date (Notarangelo et al. 2007). The incidence of PIDs is low,
but their prevalence can range from 1 in 500 to 1 in 500000
in the general population depending on clinical awareness
and medical resources available in different countries. Multi-
organ granulomatous disease of unknown etiology can occur
in a number of PID including common variable immune
deficiency (CVID), severe combined immunodeficiency,
ataxia telangiectasia, Wiskott Aldrich syndrome and unclas-
sified combined immunodeficiency. All these conditions are
characterized by functional defects in the humoral and cell
mediated immune systems. It remains a matter of debate as
to whether granulomatous disease associated with PID
represents an immune response to an as yet unidentified
pathogen, the occurrence of sarcoidosis in an immune
deficient patient, or in the case of CVID a unique disease.
CVID is the most common symptomatic PID affecting
adults, so this chapter will largely concentrate on granulo-
matous disease in CVID.
