[Challenges in the evaluation of patients with inborn errors of immunity following the implementation of the 20-valent pneumococcal conjugate vaccine].

Abstract

The advent of the 20-valent pneumococcal conjugate vaccine (PCV20) in Argentina is a tool to optimize the prevention of invasive pneumococcal disease. Nonetheless, this new vaccine has complicated the diagnosis of selective antibody deficiency (SAD), an inborn error of immunity characterized by an inadequate response to the polysaccharide antigens present in the 23-valent pneumococcal polysaccharide vaccine (PPSV23). The withdrawal of PPSV23 and the introduction of PCV20 hinder the evaluation of polysaccharide responses, given that PCV20 induces a T-dependent immune response. This review examines the current diagnostic criteria for SAD and the limitations of available diagnostic tests in the context of these vaccine changes. Alternative strategies for measuring polysaccharide antibodies are discussed, and the need to maintain PPSV23 availability for a specific patient cohort is emphasized.