# Diagnostic Factors Associated with Sarcoidosis in Patients Referred for EBUS-TBNA Due to Mediastinal Lymphadenopathy

## TL;DR

The study identifies factors that help predict sarcoidosis diagnosis in patients undergoing a specific lung procedure, potentially reducing unnecessary tests.

## Contribution

A new clinical scoring system is developed to estimate sarcoidosis likelihood using pre-procedural data.

## Key findings

- Younger age, female sex, and normal white blood cell count are linked to higher sarcoidosis diagnosis likelihood.
- A scoring system based on clinical and radiological factors stratifies patients into diagnostic probability groups.
- The system may reduce unnecessary repeat procedures by guiding diagnostic expectations.

## Abstract

What are the main findings?
In patients undergoing first-time EBUS-TBNA for mediastinal lymphadenopathy, younger age (≤55 years), female sex, absence of a pulmonary mass >10 mm, normal white blood cell count, and typical clinical features are associated with a higher likelihood of a definitive sarcoidosis diagnosis.A simple clinical scoring system based on routinely available pre-procedural data stratifies patients into low-, intermediate-, and high-probability diagnostic groups.

In patients undergoing first-time EBUS-TBNA for mediastinal lymphadenopathy, younger age (≤55 years), female sex, absence of a pulmonary mass >10 mm, normal white blood cell count, and typical clinical features are associated with a higher likelihood of a definitive sarcoidosis diagnosis.

A simple clinical scoring system based on routinely available pre-procedural data stratifies patients into low-, intermediate-, and high-probability diagnostic groups.

What are the implications of the main findings?
The proposed scoring system may assist clinicians in estimating the likelihood of sarcoidosis before EBUS-TBNA and in discussing diagnostic expectations with patients.Identification of low- and high-probability groups may help guide the intensity of further diagnostic work-up and reduce unnecessary repeat invasive procedures.

The proposed scoring system may assist clinicians in estimating the likelihood of sarcoidosis before EBUS-TBNA and in discussing diagnostic expectations with patients.

Identification of low- and high-probability groups may help guide the intensity of further diagnostic work-up and reduce unnecessary repeat invasive procedures.

Sarcoidosis is a multisystem granulomatous disease of unknown aetiology that frequently presents with mediastinal lymphadenopathy and often requires invasive diagnostic procedures. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is widely used in this setting; however, a definitive diagnosis cannot always be established at first attempt. This study aimed to identify clinical, laboratory, and radiological factors associated with a definitive diagnosis of sarcoidosis in patients referred for EBUS-TBNA. A retrospective analysis was performed including patients undergoing first-time ever EBUS-TBNA for mediastinal lymphadenopathy over a 12-month period. Demographic data, clinical features suggestive of sarcoidosis, chest computed tomography findings, and white blood cell count, were analysed, and definitive diagnoses were established based on cytological results and available follow-up data. Younger age (≤55 years), female sex, the absence of a pulmonary mass >10 mm on imaging, normal white blood cell count, and the presence of clinical features typical of sarcoidosis were significantly associated with a definitive diagnosis of sarcoidosis. Based on these variables, two point-based diagnostic scoring models were developed, demonstrating clinically relevant discriminatory performance. Readily available pre-procedural clinical and radiological factors may assist in estimating the probability of sarcoidosis in patients undergoing EBUS-TBNA for mediastinal lymphadenopathy and may support risk stratification and clinical decision-making.