Update: Primary immunodeficiency disorders among north Indian children

Primary immunodeficiency disorders (PIDs) are a group of genetic abnormalities characterized by defectin one or more constituents of the immune system.This group of disorders are largely undiagnosed and unreported worldwide due to lack of awareness among the medical practitioners,parents as well as lack of state of art diagnostic facilities. Earlier we had reported the distribution pattern of various categories of PID in children of north India; in this report we are appending the data with current findings.In this retrospective study we pooled data from PIDs workup of 706 children with suspected PIDs, below the age of 18Yrs, in the period of May 2017 October 2019. The clinical assessment and presentation of these children was suggestive of PID. The peripheral blood of these children was used for flow cytometry based immunophenotyping of immune cells. PIDs were classified according to the International Union of Immunological Societies’ (IUIS) criteria.A total of 133 (18.38%) children were diagnosed with one or other form of PID with overall median age was 3.25 years (male: 2.3 and female: 4.2Yrs). Chronic infection, persistent diarrhea and retarded growth were the common warning signsin these patients. Combined humoral and cellular immunodeficiency was observed in 32%, phagocytic defect in 23%, antibody defect in 17%, dysregulated innate immunity in 19% and other well defined syndromes in 9% of total diagnosed PID children. Around 15.78% of PID cases were seen in coupleswithconsanguineous marriage, past family history of PID in 20.30% and families with sibling death of unknown cause in 24.06%. The cause of death of the sibling was not known. PID diagnosed children received prophylactic antibiotics and/or antifungals in addition tospecific therapy for the underlying immune deficiency.The field of PID remainsunexplored worldwide. The awareness in the developed countries is more than that of developing countries like India. The developing countries face several challenges in the diagnosis of PIDs such as awareness among patients and medical practitioners, mostly in the rural settings, lack of sufficient number of tertiary care centres, lack of equipped immunological laboratory to diagnose the disease.