A Case of Mediastinal Abscess Diagnosed by Endoscopic Ultrasound

ABSTRACT

Endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) plays an important role in the diagnosis of benign and malignant mediastinal lesions. However, it is mostly used for the biopsy of consolidated lesions and enlarged lymph nodes. This paper presents a case of mediastinal abscess diagnosed by endobronchial ultrasound‐guided puncture.

This paper presents a case of mediastinal abscess diagnosed by endobronchial ultrasound‐guided puncture.

A 53‐year‐old male patient presented with chronic cough and expectoration as the main symptoms. Chest computed tomography (CT) revealed consolidation and cavity formation in the right upper lobe (Figure 1A). A mediastinal abscess was observed on the posterior wall of the tracheal carina (Figure 1B). Flexible bronchoscopy showed no abnormal findings in the tracheal mucosa (Figure 2A). Bronchoalveolar lavage was performed in the right upper lobe, and no pathogenic microorganisms were detected in the bronchoalveolar lavage fluid (BALF) submitted for microbiological examination. Subsequently, radial endobronchial ultrasound‐guided guide sheath transbronchial lung biopsy (r‐EBUS‐GS‐TBLB) was conducted in the consolidated area of the apical segment of the right upper lobe (Figure 2B). EBUS‐TBNA was performed on the posterior wall of the carina. A liquid lesion with multiple internal septations was detected by ultrasound (Figure 2C). Yellow fluid was aspirated after puncture, and Mycobacterium tuberculosis was identified by metagenomic next‐generation sequencing (mNGS). Histopathological examination of the biopsied lung tissue from the right upper lobe revealed chronic granulomatous inflammation (Figure 3). Anti‐tuberculosis therapy was subsequently administered.

FIGURE 1.

(A) CT of the thorax showed the right upper lobe consolidation with cavity formation (black arrows). (B) mediastinal abscess at the posterior wall of the tracheal carina (black arrows).

FIGURE 2.

(A) Apical segment of the right upper lobe. (B) ultrasound image showing consolidation in the apical segment of the right upper lobe (white arrows). (C) ultrasound imaging showed septations in the abscess at the posterior wall of the carina (white arrows).

FIGURE 3.

Pathological examination revealed granulomatous lesions (black arrows) (Haematoxylin and eosin staining; ×200).

Bronchoscopy serves as a vital tool in the diagnosis of tuberculosis infection [1, 2, 3]. However, conventional bronchoalveolar lavage exhibits certain limitations in the evaluation of chronic infections and encapsulated lesions. In this case, EBUS‐TBNA was used to puncture the mediastinal abscess, leading to a diagnosis of tuberculous cold abscess, which provides a novel approach and strategy for the diagnosis of such lesions.

Author Contributions

All authors contributed to the writing, review and final approval of the manuscript.

Funding

The authors have nothing to report.

Ethics Statement

Patient consent has been obtained prior to submission. Participants gave informed consent to participate in the study before taking part.

Consent

I attest that the patient described in the manuscript, or their proxy, has completed and signed the consent form provided by Respirology Case Reports. I attest that the original of the signed form is held by the treating institution.

Conflicts of Interest

The authors declare no conflicts of interest.

Wang Q., Jia C., Shen Q., and Shi M., “A Case of Mediastinal Abscess Diagnosed by Endoscopic Ultrasound,” Respirology Case Reports 14, no. 3 (2026): e70550, 10.1002/rcr2.70550.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.