Falsely elevated type IV collagen caused in part by heterophilic antibodies: A case report

Immunoassays, which are used ubiquitously in clinical practice, are inherently vulnerable to distortions arising from endogenous immunoglobulins, particularly heterophilic antibodies. While many studies have explored interference in substances measured using chemiluminescence or electrochemiluminescence methods based on the double-antibody sandwich principle, there are limited data on interference in immunoturbidimetric assays, particularly for type IV collagen. This article presents the first report of a noteworthy increase in serum type IV collagen levels stemming from heterophilic antibody interference detected through an immunoturbidimetric assay. The present study investigated the mechanisms of this interference and the differences introduced by heterophilic antibodies between the two methodologies. Additionally, it outlines strategies for identifying and mitigating such interference, and discusses the principles, limitations, and considerations of each corrective approach. The objective is to raise awareness among clinical laboratory professionals concerning the potential interference of heterophilic antibodies in immunoturbidimetric assays. Increased awareness will aid in the prompt detection and correction of this issue, ensuring the provision of accurate and reliable laboratory data for informed clinical decision-making and the prevention of adverse medical outcomes.