Abstract

Objective: Inborn errors of immunity (IEI), formerly known as primary immunodeficiencies, are a group of inherited diseases affecting different innate and adaptive immune system components. The most common finding in the heterogeneous group of patients with IEI is infections, which are associated with increased morbidity and mortality. This retrospective study aims to determine infections in a heterogeneous group of patients receiving immunoglobulin replacement therapy (IGRT).

Methods: The medical records of the patients with IEI who received IGRT and were followed up in our clinic for the last five years were reviewed retrospectively.

Results: In this study, including 45 patients diagnosed with IEI (55.6% male, average age 38.4±11.6 years), the most common subgroup was primary antibody deficiencies (40, 88.8%). The average age of diagnosis for patients was 26.8±14.8 years, with a median diagnostic delay of 6 years. Twenty (44.4%) of patients had bronchiectasis. All patients were receiving IGRT, with 82.2% using antimicrobial prophylaxis. Before diagnosis, the median annual number of infections was 4, which decreased to 1 post-treatment (p<0.001). Significant reductions in pneumonia and upper respiratory tract infection frequency were observed with IGRT compared to before the treatment (75.6% vs. 22.2%, p<0.001; 66.7% vs. 31.1%, p=0.003). Seventeen (37.8%) of patients were hospitalized due to infections during treatment. The rate of inactive influenza vaccination and the average body mass index (BMI) were significantly lower in patients with hospitalization than in those without hospitalization (20% vs 53.8%, p=0.034; 20.5 vs. 24.1 kg/m², p=0.019). Among those with bronchiectasis, the rate of pneumonia prior to diagnosis was significantly higher (95% vs. 60%, p=0.012). Lower BMI, the presence of bronchiectasis, and non-compliance with treatment were associated with more frequent infections under treatment.

Conclusion: Many complications, especially infections, can be prevented by early diagnosis and treatment of IEI and increasing patient compliance with treatment. Therefore, increasing awareness of IEI both in society and among physicians from all specialties will enable patients to be diagnosed at an early stage and reduce hospitalization, mortality and morbidity.