Diversity in the Clinical Course and Outcome of COVID-19 in Patients with Different Inborn Errors of Immunity can be Associated with the Type of Error.

Background: The relationship between inborn errors of immunity (IEIs) and COVID-19 severity and incidence rates remains unclear due to limited and diverse data. This study aimed to address this gap by identifying specific IEIs associated with an increased risk of severe COVID-19 or a predisposition to severe disease before vaccination. Materials and Methods: Data were collected from the medical records of 15 patients with various IEIs, supplemented by interviews with individuals from an IEIs registry who had experienced COVID-19 before vaccination. Results: Among the participants, only three patients (20%) experienced severe-prolonged COVID-19. Notably, this severity was predominantly observed in two male patients with Bruton's disease (BD) and one female patient with autosomal recessive hypogammaglobinemia. Moderate and severe COVID-19 cases were equally distributed (13.33%). In the female subgroup, one patient with common variable immunodeficiency and another with combined immunodeficiency experienced moderate and severe COVID-19, respectively. Conversely, both male patients with moderate and severe COVID-19 had BD. Conclusion: Despite the limited number of severe cases, the absence of cytokine storm manifestation suggests potential protective mechanisms, possibly due to intravenous immunoglobulin therapy and inherent deficiencies within cytokine-producing cells (B and T cells). While IEIs may not be significant risk factors for COVID-19, they offer promising avenues for further research into therapeutic strategies targeting specific immune system components to mitigate severe COVID-19.