Types of PI

Patients with persistently low levels of one or two IgG subclasses and a normal total IgG level have a selective IgG subclass deficiency.

Deficiencies of the cytokine, IL-21, and IL21 receptor has been described in children with very early onset inflammatory bowel disease, liver disease, and immunodeficiency with T cell and B cell defects.

Short for immunodeficiency-centromeric instability facial anomalies syndrome, ICF syndrome is an autosomal recessive disorder that may be due to variants in the ZBTB24, DNMT3B, CDCA7, or HELLS genes.

People with deletions of multiple genes in the immunoglobulin heavy chain region can be asymptomatic or can exhibit susceptibility to infections.

Innate immune disorders include Myd88 and IRAK-4 deficiencies, TLR3 deficiency, NF-kappa-B essential modulator (NEMO) deficiency syndrome, natural killer (NK) cell deficiency, and disorders in interferon-γ (IFN-γ) and interleukin (IL)-12/23 signaling pathways. 

IPEX is an X-linked disorder in which affected boys develop severe autoimmunity that can target any organ. The gut, skin, and endocrine organs—particularly the pancreas and thyroid gland—are the most common targets.