Late-diagnosed pea aspiration in an adult mimicking a mass-like right lower-lobe lesion and requiring basal segmentectomy: A case report

Abstract

Tracheobronchial foreign body aspiration (FBA) is potentially life-threatening. In adults, delayed diagnosis may occur because symptoms are nonspecific and organic foreign bodies can be radiolucent, leading to recurrent infection, granulation tissue, and surgical resection. A 46-year-old Arab man with hypertrophic cardiomyopathy and hypertension presented with fever, productive cough, and grade II dyspnea 15 months after accidental pea aspiration. Chest computed tomography (CT) demonstrated a focal basal right lower-lobe mass-like consolidation, corresponding to the surgically treated basal segments, without a definite radiopaque intraluminal foreign body. Flexible bronchoscopy achieved only partial removal, and histopathology confirmed plant material with nonspecific chronic inflammation. Despite conservative treatment, he deteriorated with foul-smelling purulent sputum and persistent inflammation. Because of failed conservative/endoscopic management, bronchial strictures, and vegetative inflammatory lesions, he underwent right lower-lobe basal segmentectomy via thoracotomy. Surgery revealed marked induration, consolidation, and a purulent collection. Final pathology showed chronic suppurative inflammation with lymphoid follicles and purulent material, plus a 1.3-cm sclerosing nodule with papillary formations; immunohistochemical evaluation was requested to further exclude an associated neoplastic process. At 2-week follow-up, he improved clinically, and chest radiography showed no residual or recurrent focal mass-like consolidation. Adult FBA may mimic malignancy or chronic infection. CT is essential for identifying secondary postobstructive changes, although the foreign body may not be directly visible. Delayed presentation increases the risk of granulation, infection, and failed bronchoscopic retrieval. Delayed organic FBA should be considered in persistent focal lower-lobe consolidation; early CT and bronchoscopy may prevent complications and surgery.

Introduction

Tracheobronchial foreign body aspiration (FBA) is a potentially life-threatening airway event that is encountered most frequently in children and older adults, although it may occur at any age [1]. While FBA is relatively uncommon in adults, adult cases remain clinically important because the presentation may be subtle, nonspecific, or incorrectly attributed to more common respiratory disorders such as pneumonia, chronic bronchitis, asthma, or malignancy [[2], [3], [4]]. In pediatric populations, organic food materials are common aspirates, whereas adult aspirates are more heterogeneous; however, food and other organic materials remain important causes of aspiration across age groups [[1], [2], [3]]. Prolonged retention of organic foreign bodies is particularly relevant because it may promote postobstructive infection, granulation tissue, bronchial stenosis, bronchiectasis, and radiologic appearances that can mimic inflammatory or neoplastic disease [[1], [2], [3], [4]].

Imaging plays a central but imperfect role in the evaluation of suspected FBA. Plain chest radiography may be normal or may demonstrate only indirect findings, particularly when the aspirated material is radiolucent or organic [[1], [2], [3], [4]]. Computed tomography (CT) is more sensitive than chest radiography for detecting airway foreign bodies and for characterizing secondary postobstructive changes, including focal consolidation, atelectasis, bronchiectasis, air trapping, or an endobronchial mass-like appearance [[1], [2], [3], [4]]. Nevertheless, CT findings may remain diagnostically challenging, as retained foreign material and surrounding inflammatory reaction can resemble malignancy or chronic infection; therefore, correlation with clinical history and bronchoscopic confirmation is often required [1,2,5].

We report a late-diagnosed case of organic FBA caused by pea aspiration in an adult, presenting as a mass-like posterior basal right lower-lobe lesion with postobstructive infectious changes and ultimately requiring basal segmentectomy after incomplete bronchoscopic removal. This case highlights the need for radiologists to consider delayed organic FBA in adults with persistent or recurrent focal lower-lobe consolidation, especially when imaging suggests postobstructive disease and the aspiration event is remote, forgotten, or initially underemphasized.

Case presentation

A 46-year-old Arab man, a former waterpipe smoker with hypertrophic cardiomyopathy and arterial hypertension, presented with fever, productive cough, and grade II dyspnea 15 months after an accidental episode of pea aspiration. His long-term medications included nebivolol, ranolazine, and antihypertensive therapy, and he had a history of systemic corticosteroid exposure following COVID-19 infection.

Chest CT obtained at presentation demonstrated a focal mass-like consolidation in the basal right lower lobe, predominantly involving the posterior/basal region and corresponding to the surgically targeted basal segments. The lesion was peripheral/subpleural and associated with surrounding postobstructive inflammatory change. No definite radiopaque or calcified intraluminal foreign body was directly identified on the available CT images, consistent with the organic and radiolucent nature of the aspirated pea. No obvious cavitation was appreciable on the provided sections. Based on the CT appearance alone, the main radiologic differential diagnoses included postobstructive pneumonia secondary to an occult endobronchial lesion, primary lung malignancy, organizing pneumonia, and lung abscess or necrotizing infection. However, the remote aspiration history, persistent focal lower-lobe abnormality, and subsequent bronchoscopic findings favored delayed organic foreign body aspiration with postobstructive infection (Fig. 1).

Fig. 1.

Axial chest CT images in lung and mediastinal windows showing a focal peripheral/subpleural mass-like consolidation in the basal right lower lobe, corresponding to the surgically treated basal segments. No definite radiopaque intraluminal foreign body is directly visible on these images, consistent with the organic radiolucent nature of the aspirated pea. The imaging appearance favored postobstructive inflammatory/infectious change in the appropriate clinical context, although malignancy and other mass-like inflammatory lesions were considered radiologic differentials.

Flexible bronchoscopy demonstrated obstructive inflammatory changes and achieved only partial removal of the foreign body. Histopathologic examination of the retrieved material confirmed plant material with nonspecific chronic inflammation. Despite conservative management, the patient clinically deteriorated, developing foul-smelling purulent sputum and persistent inflammatory findings. Given the failure of conservative and endoscopic management, together with bronchoscopic evidence of bronchial strictures and vegetative inflammatory lesions, surgical treatment was pursued approximately 1 month after the initial bronchoscopy.

The patient underwent right lower-lobe basal segmentectomy via thoracotomy. Intraoperatively, the involved lung parenchyma was markedly indurated and consolidated, with a purulent collection. Postoperatively, he received broad-spectrum antibiotic therapy and mucolytic treatment, with subsequent clinical and oxygenation improvement. Final histopathologic examination of the resected specimen showed chronic suppurative inflammation with lymphoid follicles and purulent material, in addition to multiple inflammatory foci and a 1.3-cm sclerosing nodule with papillary formations. Immunohistochemical evaluation was requested to further characterize the papillary component and exclude an associated neoplastic process. At 2-week follow-up, the patient had improved clinically, and follow-up chest radiography showed no residual or recurrent focal mass-like consolidation (Fig. 2).

Fig. 2.

Follow-up chest radiographs obtained 2 weeks after right lower-lobe basal segmentectomy showing no residual or recurrent focal mass-like right lower-lobe consolidation. The educational value of this radiograph is limited compared with CT and is mainly included to document early postoperative radiographic follow-up.

Discussion

This case highlights the radiologic challenge of delayed organic foreign body aspiration in adults, particularly when the aspirated material is radiolucent and the dominant imaging manifestation is a focal mass-like postobstructive lesion rather than a directly visible foreign body. Although tracheobronchial foreign body aspiration is more commonly encountered in children and older adults, adult cases may present late with nonspecific symptoms and may mimic more common pulmonary conditions, including recurrent pneumonia, chronic airway disease, or malignancy [[1], [2], [3], [4]]. In the late-diagnosis cohort reported by Kara et al. [1] 17.6% of foreign body aspiration cases were diagnosed late, the mean estimated residence time was 22.8 months, and the most common symptoms were cough and dyspnea; importantly, organic materials accounted for a substantial proportion of aspirated foreign bodies [1]. Our patient similarly presented 15 months after pea aspiration with fever, productive cough, dyspnea, and subsequent purulent sputum, reflecting the indolent inflammatory course that may follow retained organic material.

Imaging is central to the evaluation of suspected foreign body aspiration, but its findings may be indirect. Plain radiographs may be normal or nonspecific, especially when the aspirated object is radiolucent [1,2,4]. CT is more sensitive for evaluating airway obstruction and secondary parenchymal changes, including consolidation, atelectasis, bronchiectasis, air trapping, and postobstructive infection [1,6,7]. However, CT may still be nondiagnostic when the foreign body is organic or incorporated within inflammatory tissue. In our case, the available CT images did not show a definite radiopaque intraluminal foreign body; instead, they demonstrated a focal mass-like consolidation in the basal right lower lobe. Therefore, the principal radiologic differential diagnoses included postobstructive pneumonia secondary to an occult endobronchial lesion, primary lung malignancy, organizing pneumonia, and lung abscess or necrotizing infection. The remote aspiration history, persistent focal lower-lobe abnormality, and later bronchoscopic/pathologic confirmation supported delayed organic foreign body aspiration.

A key teaching point for radiologists is that chronic foreign body aspiration may simulate malignancy. Retained airway foreign bodies can produce granulation tissue, chronic suppurative inflammation, bronchial stenosis, and mass-like endobronchial or parenchymal abnormalities [1,[6], [7], [8]]. A previously reported adult case of green pea aspiration appeared as an enhancing endobronchial nodule and was initially suspected to represent an endobronchial tumor before bronchoscopic extraction confirmed the foreign body [7]. Similarly, foreign body-related obstruction caused by organic vegetable material has been reported to mimic lung cancer when associated with bronchial obstruction, cavitation, nodular shadows, and inflammatory laboratory findings [8]. In our patient, the mass-like CT appearance and the later histopathologic finding of a papillary sclerosing component appropriately prompted further evaluation to exclude an associated neoplastic process.

The need for surgery in this case was related to the chronicity and complications of the retained organic foreign body rather than to the initial imaging appearance alone. Bronchoscopy is usually the diagnostic and therapeutic cornerstone of adult foreign body aspiration, but delayed presentation may reduce the likelihood of complete endoscopic removal because of granulation tissue, airway narrowing, suppuration, and distal postobstructive damage [[1], [2], [3],6]. Organic foreign bodies may also fragment, migrate distally, or induce a pronounced inflammatory response, making complete clearance difficult [[9], [10], [11]]. In selected cases, advanced bronchoscopic techniques, including cryoprobe-assisted retrieval, may avoid surgery [11]. In our patient, however, bronchoscopy achieved only partial removal, and the combination of bronchial strictures, vegetative inflammatory lesions, persistent purulent infection, and failure of conservative management led to basal segmentectomy. The postoperative clinical improvement and absence of recurrent focal mass-like consolidation on follow-up radiography support the interpretation that the lesion represented chronic post-obstructive inflammatory disease secondary to delayed pea aspiration.

Conclusion

Adult tracheobronchial foreign body aspiration can present late with nonspecific symptoms and radiologic findings that mimic malignancy or chronic infection. Our case highlights that prolonged retention of an organic foreign body may lead to postobstructive infection, airway strictures, and failure of endoscopic removal, ultimately requiring surgical resection. Maintaining a high index of suspicion, performing CT when chest radiography is inconclusive, and pursuing early bronchoscopy are key to minimizing complications and improving outcomes.

Ethics approval

Institutional Review Board (IRB) approval is not required for de-identified single case reports or case histories, in accordance with institutional policies.

Patient consent

Written informed consent was obtained from the patient for publication and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.