False-positive Results of Quantiferon-Tb-Gold Assay in Children.

We present a pediatric case series describing false-positive QuantiFERON-TB Gold In-tube (QFT-GIT) assay (QIAGEN, Germany) results observed in a tertiary hospital in Spain (2013-2018). During the study period, 7 of 737 test results were considered false-positives: 4 children with chronic medical conditions, 1 Mycobacterium lentiflavum lymphadenitis, 1 infant born to a mother with pulmonary tuberculosis, and 1 child exposed to a noninfectious tuberculosis patient. Data regarding interferon-gamma release assays false-positive results in children are scarce, and more studies are necessary to determine the rates of false-positive results in low-prevalence settings.