Elevated nil values in TB-IGRA: a potential diagnostic clue for pediatric histiocytic necrotizing lymphadenitis.
Elevated TB-IGRA Nil value helps distinguish pediatric histiocytic necrotizing lymphadenitis from mimics
Elevated nil values in TB-IGRA: a potential diagnostic clue for pediatric histiocytic necrotizing lymphadenitis.
Histiocytic necrotizing lymphadenitis (histiocytic necrotizing lymphadenitis) is a benign condition in children that is often misdiagnosed due to its clinical overlap with tuberculosis, rheumatic diseases, and lymphadenitis.
To investigate the relationship between TB-Nil values and the diagnosis of histiocytic necrotizing lymphadenitis, we retrospectively enrolled 48 patients who were diagnosed with histiocytic necrotizing lymphadenitis at the Women and Children's Medical Center, Guangzhou Medical University, between January 2019 and December 2024 and who had undergone TB-IGRA testing.
higher TB-Nil reliably separates histiocytic necrotizing lymphadenitis from mimics; AUROC, 1.0 is perfect
Among the 48 enrolled patients with suspected histiocytic necrotizing lymphadenitis, 37 were confirmed by pathological diagnosis and the remaining 11 were diagnosed based on clinical criteria.
The median Nil level was significantly elevated in histiocytic necrotizing lymphadenitis patients [0.82 IU/mL, interquartile range (IQR): 0.36-1.18] compared with patients with systemic juvenile idiopathic arthritis (sJIA, median = 0.07 IU/mL, P < 0.0001), Kawasaki disease (kawasaki disease, median = 0.09 IU/mL, P < 0.0001) and Bacterial Lymphadenitis (bacterial lymphadenitis, median = 0.09 IU/mL, P < 0.0001).
The routinely available yet often overlooked Nil value from the TB-IGRA is significantly elevated in pediatric histiocytic necrotizing lymphadenitis and demonstrates favorable diagnostic accuracy.
It may serve as a practical, non-invasive adjunctive biomarker for the early differential diagnosis of histiocytic necrotizing lymphadenitis from other inflammatory diseases.
Prospective multi-center studies are warranted to validate these findings.