Current Approach to Primary Immunodeficiency Diseases

Abstract

Primary immunodeficiency diseases (PIDD) are inherited disorders resulting from defects in diverse elements of the human immune system. Currently, more than 330 PIDDs have been described, and the molecular (genetic) bases for more than 320 of them are known. PIDD can be divided into nine different groups, including antibody (humoral) deficiencies, innate/intrinsic deficiencies, phagocytic system deficiencies, complement component deficiencies, combined (T and B cells) immunodeficiencies, syndromic combined immunodeficiencies, immune dysregulation disorders, autoinflammatory diseases and phenocopies of PIDD. In the PIDD group, primary antibody deficiencies are the most common group, and approximately 50% of patients with PIDD fall into this group of deficiencies. Congenital primary immunodeficiencies typically appear early in life, although late onset is gradually more identified. Affected patients usually present clinically with recurrent/ severe infections, or clinical pictures resembling various autoimmune or other diseases. An early diagnosis of congenital immunodeficiencies is necessary for transfer to specialized medical centers, and prompt commencement of the optimal treatment, including transplantation and enhanced outcomes. In this review, a general approach is described for the investigation of the most common groups of PIDD, outlining the most appropriate laboratory investigations when the clinician comes across typical clinical pictures and/or infections suggesting immunodeficiency.

Demographic and clinical characterization of pediatric group patients with inborn errors of the immune system in a Colombian tertiary hospital

“…The clinical presentation is highly variable, but most present as recurrent infections, which are common in childhood and therefore may go unnoticed in the primary care setting. 1,2,18 We found that the most frequent group according to the IUIS 2015 classification was predominantly antibody deficiency, which is consistent with the international literature, 1,9 followed by CID with associated or syndromic features and then immunodeficiencies affecting cellular and humoral immunity. LASID announced that it had a registry of 8383 patients with innate errors of the immune system by August 2020, of which 53.2% had a predominantly antibody deficiency.…”

“…Most of them present at an early age as recurrent or severe infections, malignancy, or dysregulation in the immune response; autoinflammation; autoimmunity; or allergic disease. 1,2 In 1970, the World Health Organization created a committee to classify these pathologies. 3 Subsequently, in 2015, the International Union of Immunological Societies Expert Committee for Primary Immunodeficiency (IUIS) modified the classification, given the recent advances of the last 40 years, with the aim to increase awareness, facilitate recognition, standardize nomenclature, standardize the approach, and promote optimal and early treatment for these patients.…”

Primary Immunodeficiency Diseases in the Newborn

“…Initial evaluation in the newborn also includes serum Ig levels. However, measuring quantitative Ig levels (IgG, IgA, IgM, and IgE) are less useful in neonate, because neonates produce only small amount of Igs and most of the IgG in early infancy is transferred IgG from the mothers [ 8 , 10 , 11 , 22 , 23 ].…”