Bronchoscopy Clinic: A patient with "worsening asthma"

A 45-year-old man was referred to our pulmonary clinic for progressive dyspnea and worsening asthma. His shortness of breath had been worsening over the past 2 years. He denied fever, weight loss, and other systemic complaints.

Asthma had been diagnosed in the patient 9 years earlier. He was receiving inhaled corticosteroids and bronchodilators; he was not taking systemic corticosteroids. His medical history was significant for hypertension.

The patient had no history of cerebrovascular events, swallowing difficulties, or significant dental problems. He had no history of tobacco use, and he denied any alcohol or drug abuse.

On examination, the patient was in no distress and was afebrile. Pulse oximetry indicated an oxygen saturation of 97% on room air. No lymphadenopathy or clubbing was detected.

The lung examination revealed wheezing, which was more prominent on the right anterior chest wall. The rest of his physical examination was unremarkable.

Laboratory results revealed normal complete blood cell count and serum chemistries. Serum IgE levels were normal.

Findings on chest radiography revealed no parenchymal abnormalities. A CT scan of the chest demonstrated significant narrowing of the bronchus intermedius, mild bronchiectasis of the right lower lobe with patchy infiltrates, and 2 small nodules (Figure 1).

The patient underwent fiberoptic bronchoscopy, which revealed an endobronchial mass causing near-total occlusion of the bronchus intermedius with severe mucosal inflammation and edema, mimicking endobronchial tumor. The mucosa was extremely fria- ble and started bleeding. The endobronchial biopsy specimen is shown below (Figure 2).

Making the diagnosis

Pathology of the endobronchial biopsy specimen revealed many large colonies of Actinomyces species ("sulphur granules"), which were surrounded by inflammatory cells. The diagnosis was endobronchial actinomycosis.

Discussion

Actinomyces species are filamentous Gram-positive bacteria that belong to the family Actinomycetaceae. These commensal of the oropharynx and GI tract are found in 30% to 50% of normal saliva specimens.¹

Tissue invasion is rare and generally requires interruption of the mucosal barrier.¹ Most (50% to 60%) Actinomyces infections manifest as the cervicofacial type, although the infection can affect virtually any organ. The prevalence of the pulmonary form of actinomycosis is believed to be about 15% to 20%.^2,3

Primary endobronchial actinomycosis is very rare and results from aspiration of infected material from the oral cavity.⁴ Because of its rarity, indolent nature, and ability to mimic other diseases, this infection is difficult to diagnose. It is often misdiagnosed as lung cancer.² Thus, many cases are diagnosed after surgical resection.^5,6

Endobronchial actinomycosis is a rare form of pulmonary actinomycosis⁷ that has been reported to be associated with foreign-body aspiration. To the best of our knowledge, 14 cases of endobronchial actinomycosis associated with foreign-body aspiration have been reported in the English literature.^4,8,9 All the patients were older than 50 years, and 12 of 14 were men. These patients had known risk factors for actinomycosis, including chronic debilitated state and poor dental hygiene.

The clinical presentation was characterized by cough, hemoptysis, and recurrent pneumonia. Only 1 of the patients reported a history of choking.⁹

CT scans showed radiopaque foreign bodies in 5 of 13cases.^4,8,9 Other radiologic findings included consolidation, atelectasis, bronchiectasis, and pleural effusion.^4,8,9

The initial bronchoscopy findings were similar in all the cases and revealed an endobronchial mass obstructing the bronchial lumen, suggesting malignancy. As expected, the right bronchus was usually (in 86% of cases) involved.

Foreign bodies were detected immediately in only 5 (35%) of 14 cases. Chicken bone was the most common foreign body associated with endobronchial actinomycosis, followed by organic seeds, tooth, and fish bone.^4,8,9

In conclusion, endobronchial actinomycosis associated with foreign-body aspiration rarely causes endobronchial masses and atelectasis. The clinical history and physical examination are the cornerstone of further workup.

Fiberoptic bronchoscopy is the initial method of diagnosis and should be repeated a few weeks after the initiation of antibiotic therapy, specifically to look for a foreign body that may have been missed during the initial examination. In most cases, antibiotic therapy directed against the pathogen results in a complete cure.

Outcome of this case

The patient was given intravenous ceftriaxone via a peripherally inserted central catheter line for 6 weeks, followed by oral penicillin. Bronchoscopy repeated 4 weeks after antibiotic treatment revealed a pistachio nutshell lodged in the bronchus intermedius (Figure 3), which had become prominent after resolution of the inflammation and edema. It was successfully removed with endobronchial biopsy forceps (Figure 4).

Six weeks after treatment, the patient reported complete resolution of his shortness of breath. He was successfully weaned from all asthma medications.

Fiberoptic bronchoscopy and CT scanning repeated 3 months after treatment revealed resolution of the obstruction of the right main bronchus, with minimal residual mucosal inflammation (Figure 5).

References:

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