International Trends in Immunity

RIMARY immune deficiencies are genetic diseases caused by more than 200 single mutations. Each one of these mutations may/will affect the function of a cell activation pathway, a single cell population or a defined subset in innate or adaptive immunity.[1,2] Patients with secondary immunodeficiencies are a heterogenous group[3], comprising different disease entities: patients with HIV, patients with cancer including systemic/metastatic disease, hematological malignancies and HSCT, as well as patients on immunosuppressive treatment.[4] Secondary immunodeficiency has also been detected in patients with chronic diseases of the heart, lung, liver, kidney [5], and in patients with diabetes, with and without chronic organ involvement.[6] A large group of secondary immunodeficiency is caused by immune-suppressive treatment in solid organ transplants, cancer chemotherapy, and patients with rheumatic disease with immune suppression.[7] All of these patients are at an increased risk for infectious complications. The impairment of immune function in patients with SID often involves different levels of the immune response. Innate and adaptive immunity, as well as T-cell or B-cell function may be affected simultaneously.[8,9] Patients with combined Tand B cell involvement may present with a phenotype of severely impaired T-cell function, even resembling severe combined immunodeficiency e.g. patients with HIV and CD4-cells <200 mm3/μl and antibody failure. Patients with severe impairment of T-cell function may develop severe viral and fungal infections and bacterial infections with microorganisms of low pathogenicity, lengthy and chronic bacterial infections.[10] The most frequently diagnosed immune impairment in different forms of SID is predominantly antibody deficiency,[11,12] this may be mild or severe, with antibody response of lower height and shorter persistence[13,14], or severe up to antibody failure