<unk>  <unk> , also known as Swiss-type agammaglobulinemia, is a rare genetic disorder characterized by the disturbed development of functional T cells and B cells caused by numerous genetic mutations that result in differing clinical presentations.<unk>  involves defective antibody response due to either direct involvement with B lymphocytes or through improper B lymphocyte activation due to non-functional T-helper cells. Consequently, both "arms" (B cells and T cells) of the adaptive immune system are impaired due to a defect in one of several possible genes.<unk>  is the most severe form of primary immunodeficiencies, and there are now at least nine different known genes in which mutations lead to a form of<unk> . It is also known as the bubble boy disease and bubble baby disease because its victims are extremely vulnerable to infectious diseases and some of them, such as David Vetter, have become famous for living in a sterile environment.<unk>  is the result of an immune system so highly compromised that it is considered almost absent.<unk>  patients are usually affected by severe bacterial, viral, or fungal infections early in life and often present with interstitial lung disease, chronic diarrhea, and failure to thrive. Ear infections, recurrent Pneumocystis jirovecii (previously carinii) pneumonia, and profuse oral candidiasis commonly occur. These babies, if untreated, usually die within one year due to severe, recurrent infections unless they have undergone successful hematopoietic stem cell transplantation or gene therapy in clinical trials.
Severe combined immunodeficiency
Common variable immunodeficiency
X-linked severe combined immunodeficiency
X-linked agammaglobulinemia
Primary immunodeficiency
Combined immunodeficiencies
Chronic granulomatous disease
Adult-onset immunodeficiency syndrome