Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA): Technical Updates and Pathological Yield

Since the endobronchial ultrasound bronchoscope was introduced to clinical practice, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has become the procedure of choice to sample hilar and mediastinal adenopathy. Multiple studies have been conducted in the last two decades to look at the different technical aspects of the procedure and their effects on the final cytopathological yield. In addition, newer modes of ultrasound scanning and newer tools with the potential to optimize the selection and sampling of the target lymph node have been introduced. These have the potential to reduce the number of passes, reduce the procedure time, and increase the diagnostic yield, especially in rare tumors and benign diseases. Herein, we review the latest updates related to the technical aspects of EBUS-TBNA and their effects on the final cytopathological yield in malignant and benign diseases.

Epidemiology and clinical characteristics of childhood TB identified using active and passive case finding

BACKGROUND: Childhood TB cases can be found using passive case finding (PCF), i.e., by diagnosing children presenting with symptoms, or using active case finding (ACF), i.e., by identifying children with TB through contact tracing. Our study determined epidemiologic, clinical, and radiographic differences between these groups.DESIGN/METHODS: Retrospective cohort study of children aged 0–19 years diagnosed with TB from January 1, 2012 to December 31, 2019 at a U.S. TB clinic, comparing clinical, radiographic, microbiologic, and epidemiological characteristics of children identified using PCF and ACF.RESULTS: Of 178 eligible patients, 99 (55.6%) were diagnosed using PCF. Children identified using PCF were older (mean 8.9 vs. 6.1 years, P = 0.003), more often non-US-born (OR 2.29, 95% CI 1.12–4.67), had more extrapulmonary disease (44.4% vs. 3.8%, OR 20.27, 95% CI 5.98–68.64) and severe intrathoracic findings (39.4% vs. 10.1%, OR 5.77, 95% CI 2.50–13.29). Children identified using ACF were often asymptomatic, had isolated hilar/mediastinal adenopathy, but had more availability of drug susceptibility data from a link to a source case.CONCLUSION: Children identified using PCF had more severe manifestations, while those identified using ACF had greater availability of drug susceptibility data. Clinicians should be aware that clinical and radiographic presentations in children identified using PCF and those identified using ACF differ, and that the latter may be eligible for shorter treatment regimens.

Flip flop fungus sign: an FDG PET sign of benign pulmonary nodules

A 71-year-old man was referred to pulmonary clinic for incidental findings of hypermetabolic lung nodule and mediastinal adenopathy on CT FDG PET performed for evaluation of cough. The patient underwent bronchoscopy with endobronchial ultrasound that was non-diagnostic. The patient was subsequently sent for video-assisted thoracoscopic lymph node biopsy notable for confluent caseating granulomas due to chronic infection by Histoplasma capsulatum. Review of previous PDG PET was notable for the flip flop fungus sign—a PDG PET finding that could have altered the patients’ clinical course by potentially avoiding the need for invasive surgical tissue diagnosis.

Bilateral pleural masses in an immunocompromised patient

We present a case of persistent pleural masses with mediastinal adenopathy in an immunocompromised patient initially biopsied, diagnosed and treated for Pneumocystis jiroveci pneumonia, ultimately requiring surgical thoracoscopy to diagnose pulmonary histoplasmosis. We discuss the diagnostic approach for pleural masses in immunocompromised patients, the limitations of tissue sampling, interpretation and methodology, and pitfalls of testing in making a pathogen-specific diagnosis.

1632. Comparing the epidemiology and clinical characteristics of childhood tuberculosis through active and passive case finding

Background Childhood tuberculosis can be found via passive case finding (PCF), diagnosing a symptomatic child, and active case finding (ACF), discovering a child through contact tracing. Most high prevalence areas perform PCF, but as ACF is introduced, the clinical and radiologic findings may differ. We compare clinical, radiographic, microbiologic and epidemiological characteristics of children diagnosed through PCF and ACF. Methods A retrospective cohort study of all patients diagnosed with TB from 01/01/2012-12/31/2019 at Texas Children’s Hospital. ACF is TB in a child who had not previously sought care before identified via contact tracing, immigration screening, or screening for incarceration. Severity of disease was based on location of illness, imaging and bacteriology/histopathology. Associations between PCF/ACF and demographics, disease severity, and microbiology were analyzed. Results Of 178 patients, 80 (45%) were diagnosed via ACF. ACF patients were more likely to be US-born (OR: 2.29, [95% Confidence interval (CI): 1.12-4.67]) and younger (mean 6.18 vs 8.84 years, p= 0.016). Only 2.5% of ACF patients had extrapulmonary disease, compared to 45% of the PCF group (p< 0.0001). All 14 severe extrathoracic cases were in the PCF group (10 central nervous system disease, 3 ocular disease, 1 spondylitis). Fewer patients in the ACF group had severe intrathoracic findings (11% vs 39%, p< 0.001): miliary disease (0% vs 10%, p=0.006), cavity (1% vs 9%, p=0.04), and multilobar involvement (7.5% vs 22.4%, p=0.006). ACF patients had more hilar/mediastinal adenopathy (OR: 2.51, [CI: 1.34-3.72], p=0.004). ACF patients were less often cultured (38% vs 89%, p< 0.0001) and had less microbiological confirmation by cultures or PCR (21% vs 52%, p=< 0.0001). Conclusion Patients in the ACF group were younger, had less severe clinical manifestations, and had almost no extrathoracic disease. Clinicians need to be aware that the common clinical and radiographic presentations in children differ between PCF and ACF. Disclosures Jeffrey R. Starke, MD, Otsuka Pharmaceuticals (Other Financial or Material Support, Member, Data Safety Monitoring Board)