Severe combined immunodeficiency diagnosis and genetic defects.

Severe combined immunodeficiency (SCID) is a rare and life-threatening genetic disorder that severely impairs the immune system's ability to defend the body against infections. Often referred to as the "bubble boy" disease, SCID gained widespread recognition due to the case of David Vetter, a young boy who lived in a sterile plastic bubble to protect him from germs. SCID is typically present at birth, and it results from genetic mutations that affect the development and function of immune cells, particularly T cells and B cells. These immune cells are essential for identifying and fighting off infections caused by viruses, bacteria, and fungi. In SCID patients, the immune system is virtually non-existent, leaving them highly susceptible to recurrent, severe infections. There are several forms of SCID, with varying degrees of severity, but all share common features. Newborns with SCID often exhibit symptoms such as chronic diarrhea, thrush, skin rashes, and persistent infections that do not respond to standard treatments. Without prompt diagnosis and intervention, SCID can lead to life-threatening complications and a high risk of mortality. There are over 20 possible affected genes. Treatment options for SCID primarily involve immune reconstitution, with the most well-known approach being hematopoietic stem cell transplantation (HSCT). Alternatively, gene therapy is also available for some forms of SCID. Once treated successfully, SCID patients can lead relatively normal lives, but they may still require vigilant infection control measures and lifelong medical follow-up to manage potential complications. In conclusion, severe combined immunodeficiency is a rare but life-threatening genetic disorder that severely compromises the immune system's function, rendering affected individuals highly vulnerable to infections. Early diagnosis and appropriate treatment are fundamental. With this respect, newborn screening is progressively and dramatically improving the prognosis of SCID.

Immediate infusion-related adverse reactions to intravenous immunoglobulin in a prospective cohort of 1765 infusions.

Intravenous immunoglobulin (IVIG) is increasingly recommended for many diseases apart from primary immunodeficiency diseases (PID). Although effective and safe, adverse reactions may occur. We conducted a 2-year prospective observational study in 117 patients with PID who received regular IVIG replacement therapy at a median dose of 600 mg/kg every 3 to 4 weeks to examine IVIG's adverse effects; 1765 infusions were performed (mean=15/patient) in 75 males and 42 females (aged 3 months to 77 years) in 3 groups: ≤ 9 years (34.2%), 10-19 years (26.5%), and ≥ 20 years (39.3%). Fifty patients had common variable immunodeficiency (CVID), 11 had X-linked agammaglobulinemia (XLA), and 55 had other immune system disorders. The drugs administered were Octagam® (49.1%), Tegeline® (17.3%), Imunoglobulin® (18.6%), Flebogama® (12.9%), Vigam® (1.2%), and Kiovig® (0.4%). Immediate infusion-related adverse reactions occurred in the cases of 38 out 1765 infusions (2.15%, IC95% 1.53%-2.94%), which were classified as mild (81.6%), moderate (10.5%), or severe (7.9%). Time until reaction ranged from 10 to 240 min (mean = 85.7, median = 60). Reaction rates were similar across age groups. The most common reactions were malaise, headache, and abdominal pain. Reported severe events were tightness of the throat and seizure. All symptoms improved with temporary or complete IVIG interruption and symptomatic medications. Sixteen of 38 reactions to infusions occurred in the presence of an acute infection (p=0.09). Tegeline® represented a greater reaction risk factor than Octagam® (p < 0.001). These results indicate that IVIG infusion can be considered a safe procedure. Low reaction incidence and few severe immediate infusion-related adverse reactions were observed.