<unk>  is a form of<unk>  appearing after birth, leading to a reduction in the level of IgG, and also sometimes IgA and IgM. (The ratios of immunoglobulins vary rapidly in all infants, and the term dysgammaglobulinemia, although theoretically applicable, isn't usually used in<unk> s context.)
It can result in increased infections, but it can also present without symptoms.
Transient hypogammaglobulinemia of infancy
Selective immunoglobulin A deficiency
X-linked agammaglobulinemia
Primary immunodeficiency
Severe combined immunodeficiency
Combined immunodeficiency
Immunoglobulin M deficiency
Common variable immunodeficiency