Abstract
INTRODUCTION: Immunodeficiencies are disturbances in the immune system that can affect cell function, quantity, or both. They can be either primary, associated with genetic defects, or secondary, linked to external factors such as hemato-oncological conditions. Secondary immunodeficiencies can lead to the initiation, reactivation, or acceleration of latent, residual, or active infections, which are the leading cause of mortality. OBJECTIVE: To elucidate the occurrence and clinical characteristics of hypogammaglobulinemia in pediatric oncology patients in a high-complexity hospital in Colombia between January 2020 and December 2022. MATERIALS AND METHODS: We conducted an observational study with patients under 18 years old with a cancer diagnosis, serum immunoglobulins measurements at the time of the diagnosis, and later follow-up during treatment. RESULTS: We included 133 patients with a median age of eight years. Based on local guidelines of immunoglobulin levels for age, all patients had normal values at the time of cancer diagnosis. In the follow-up, the most significant reduction among all ages was for IgA and was related to infections and death. CONCLUSIONS: Our findings highlight the importance of measuring immunoglobulin levels at the time of the cancer diagnosis, as hypogammaglobulinemia may be linked to a poorer prognosis. Early detection could potentially improve patient outcomes.