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Introduction In 2023 extrapulmonary tuberculosis accounted for 62% of TB diagnoses in England, with mediastinal lymph node tuberculosis (MLN-TB) responsible for 14%. 1 MLN-TB symptoms vary, and it may be incidentally detected on chest imaging. Mediastinal lymphadenopathy is now routinely evaluated using endobronchial ultrasound-guided needle aspiration (EBUS-TBNA).We investigated MLN-TB diagnosed with EBUS-TBNA to estimate the frequency of asymptomatic presentations in our TB population.Methods We conducted a retrospective study of EBUS-diagnosed MLN-TB in North Central London (NCL) TB Network between 2018–2024.Cases were classified as asymptomatic (no TB-suggestive symptoms, MLN incidentally noticed on imaging) or symptomatic (if typical TB symptoms, or TB-related symptoms led to imaging).A TB diagnostic score was recorded based on the level of evidence contributing to diagnosis, as previously.2 Results 135 cases were included in the study ( table 1): 61 from the Royal Free (RFH), 50 from University College of London (UCLH), and 24 from North Middlesex (NMH) hospital.49/135 (36%) were identified as asymptomatic MLN-TB, with the remainder symptomatic.Asymptomatic MLN-TB patients were significantly older (mean age 51.2 vs 40.0 years, p=0.002) and more likely to have a history of chronic lung disease (CLD) or cancer than symptomatic individuals.Asymptomatic MLN-TB was more frequently limited to MLN involvement, compared to symptomatic TB (55.1% vs 33.7%, p=0.01).Microbiological confirmation (molecular test or culture) was obtained in similar proportions of asymptomatic and symptomatic individuals (85.7% vs 82.6%)MLN-TB symptoms varied significantly by referral route (p=0.001): inpatient referrals were mostly symptomatic, while two-week wait and other outpatient services captured more asymptomatic cases.Abstract M41 Table 1Demographic, clinical, and microbiological characteristics of patients with asymptomatic and symptomatic MLN-TB from NCL TB networkConclusions Approximately 36% of our EBUS-diagnosed MLN-TB occurred in asymptomatic individuals having imaging for unrelated indications. Asymptomatic patients were older and more often had prior lung disease or malignancy.Referral route seems to differ according to the clinical presentation of MLN-TB. The growing use of thoracic CT imaging—especially through non-TB-specific pathways—may facilitate incidental detection; mediastinal lymphadenopathy on imaging should prompt consideration of TB and early testing, even in the absence of traditional symptoms and risk factors.References UKHSA. Tuberculosis in England, 2024.McNally, et al. Int J Tuberc Lung Dis. 2025;29(5):227–30.