To investigate factors contributing to false-negative results in the interferon gamma release assay (IGRA) and provide insights for the clinical diagnosis of tuberculosis infection.

Collect patient data from the First Affiliated Hospital of Guangzhou Medical University from January 1, 2022 to November 30, 2023, who meet the enrollment requirements, and divide them into IGRA false negative group and positive group. Various indicators, including age, gender, monocyte counts, lymphocyte counts, lymphocyte ratio, total protein and albumin levels, comorbidities, T lymphocyte subsets and absolute counts, were statistically analyzed.

No significant differences (all P>0.05) were observed between the IGRA false-negative and positive groups concerning age, gender, monocyte counts, total protein levels, and comorbidities. However, statistically significant differences (all P<0.05) were noted in lymphocyte counts and ratio, albumin levels. The false-negative group had lower lymphocyte counts, lymphocyte ratio and albumin levels than the positive group. No significant difference between the two groups in the combination of diabetes, hypertension and viral hepatitis (all P>0.05). There was a significant difference in the absolute count of T lymphocyte between the two groups (P<0.05). There were no significant differences in the absolute counts of T-helper lymphocyte and T-suppressor lymphocyte between the two groups (all P>0.05). χ² analysis revealed correlation between segmented lymphocyte counts and IGRA results (P<0.05). Multifactorial logistic regression analysis indicated that lymphocyte counts and ratio, albumin levels were independent influencing factors for IGRA false-negative results.

Lymphocyte counts and ratio, albumin levels may influence IGRA false-negative results. For suspected tuberculosis patients, IGRA negative results should be interpreted in conjunction with comprehensive clinical judgment.