Pediatric Medical Genetics - S.I. Smiian 2003

Primary Immunodeficiencies
Treatment of Hereditary IDs

Definitive confirmation of the Diagnosis requires prescribing appropriate Treatment. In the case of IDS, this is not straightforward, as etiotropic therapy is virtually impossible. Numerous attempts by geneticists to find ways to correct the genetic defect in primary IDS remain at the experimental stage. Moreover, the exact cause of the pathology is not established for all primary IDS. Given the aforementioned circumstances, IDS therapy consists of the following: 1) replacement therapy for the impaired immune component; 2) active prophylaxis of the most likely infections; 3) cytokine therapy; 4) targeted replacement therapy.

Patients diagnosed with a humoral immune defect should be administered immunoglobulin preparations. Primarily, defects involving IgG are managed this way. IgG preparations (containing IgG₁ and IgG₂) are used in high doses (400 mL/kg/month). Such therapy makes it possible to eliminate recurrent infections and prevent progressive pulmonary damage. Meanwhile, the serum IgG level should be maintained at 2-4 g/L.

Primary IDS involving cellular Immunity impairment require Bone Marrow transplantation (while ensuring HLA compatibility). Good outcomes with transplantation are achieved in leukocyte adhesion deficiency and Wiskott-Aldrich syndrome. However, alongside a relatively high rate of graft rejection, this treatment method presents other challenges. First and foremost, finding an ideal HLA match for a sick child is extremely difficult. This takes a lot of time, during which the patient depletes their meager immune defenses.

Infection Prevention in children with primary IDS includes adherence to asepsis and antisepsis rules, hygienic measures, non-Structure/129.html">Specific Methods such as hardening (conditioning), and in certain cases, active immunization according to specialized protocols. Prescribing antibacterial drugs for the prevention of infectious complications is unjustified, as There is a realistic threat of fungal or antibiotic-resistant infections. In cases of persistent viral infections, it is advisable to prescribe antiviral agents (acyclovir, g-interferon).

Targeted replacement therapy is performed depending on the primary defect in specific forms of IDS. In particular, for adenosine deaminase or purine nucleoside phosphorylase deficiency, enzyme replacement is carried out by administering frozen and irradiated erythrocytes. In the case of hereditary transcobalamin deficiency (which leads to impaired B-lymphocyte function), vitamin B₁₂ is administered daily (intramuscularly, 10 mcg/kg).

It is also worth mentioning such methods for treating primary IDS as fetal Liver, Thymus, and lymphoid tissue transplantation. However, their efficacy is significantly lower than that of bone marrow transplantation.

Control Questions

1. Classification of Primary IDS.

2. Etiology of primary IDS.

3. General clinical manifestations of IDS.

4. Describe the pattern of infectious diseases in IDS depending on the defect in specific immune components.

5. Name the diagnostic methods for IDS.

6. Which diseases are caused by humoral immune deficiency?

7. Which diseases are caused by cellular immune deficiency?

8. Name combined primary IDS.

9. Clinical and paraclinical criteria for Bruton's disease.

10. Clinical and paraclinical criteria for hyper-IgM syndrome.

11. Clinical and paraclinical criteria for selective IgA deficiency.

12. Clinical and paraclinical criteria for common variable hypogammaglobulinemia.

13. Clinical and paraclinical criteria for DiGeorge syndrome.

14. Clinical and paraclinical criteria for Louis-Bar syndrome.

15. Principles of treatment for primary IDS.