Successful surgical treatment of bronchopleural fistula caused by severe pulmonary tuberculosis: A case report and review of literature

Abstract

BACKGROUND

Bronchopleural fistula (BPF) is a relatively rare, but severe complication of pulmonary tuberculosis. It is associated with significant mortality; however, its management remains a major therapeutic challenge.

CASE SUMMARY

We present a 24-year-old man with BPF resulting from severe pulmonary tuberculosis combined with mixed infections. The damaged right upper lobe and concomitant empyema were demonstrated via computed tomography. After undergoing open-window thoracostomy and tuberculosis treatment for 4 mo, decortication and right upper lobectomy were subsequently performed, leading to the resolution of tuberculosis and other concurrent pulmonary infections. Follow-up, 6 mo after surgery, failed to reveal any evidence of infection recurrence resulting in a good prognosis.

CONCLUSION

The disease course of tuberculous BPF is particularly challenging. Surgical intervention serves as an effective and safe therapeutic strategy for BPF.

Key Words: Bronchopleural fistula; Tuberculosis; Surgery; Case report

Core Tip: Bronchopleural fistula (BPF) is a relatively rare but severe complication of pulmonary tuberculosis. However, no consensus has been reached on the ideal treatment modality. This article presents a patient with a BPF resulting from severe pulmonary tuberculosis accompanied by mixed infections. Strict preoperative evaluation of surgical indications, including standard preoperative anti-tuberculosis treatment and controlling the infection through an open-window thoracostomy during surgery, can achieve a satisfactory long-term prognosis for the treatment of BPF through this three-pronged approach.

INTRODUCTION

Tuberculosis is ranked as the second leading infectious killer after coronavirus disease 2019. In 2021, 10.6 million people were diagnosed with active tuberculosis, out of which 1.6 million cases resulted in death[1]. Bronchopleural fistula (BPF) is a relatively rare but life-threatening complication of tuberculosis, with a mortality rate varying between 18% to 67%[2]. BPF most commonly manifests as a postoperative complication of pulmonary resection, particularly pneumonectomy[3]. Other common causes of BPF include lung necrosis complicating infection, persistent spontaneous pneumothorax, chemoradiotherapy, and tuberculosis[4]. The treatment of BPF involves various surgical methods, drug therapy, or bronchoscopic procedures. However, due to limited studies on the condition, there is a lack of consensus concerning its optimal treatment. The purpose of this article is to describe an effective treatment strategy for BPF caused by serious pulmonary tuberculosis.

CASE PRESENTATION

Chief complaints

A 24-year-old man was referred to our hospital with a productive cough accompanied by expectoration of purulent sputum, weight loss, and exertional polypnea. The patient was treated for tuberculosis but he subsequently developed fever and chest pain, 2 mo after being discharged from our hospital.

History of present illness

When the severity of the clinical symptoms increasingly progressed, the patient was readmitted to our hospital for further evaluation and treatment.

History of past illness

The patient had no significant medical history.

Personal and family history

The patient denied smoking previously and had no past history of lung disease. His family history was unremarkable.

Physical examination

On physical examination, the patient was in poor general condition. The patient’s body mass index was around 20. Lung auscultation indicated decreased breath sounds in the right lower lung. Chest wall collapse was evident upon visual inspection.

Laboratory examinations

Laboratory analysis evidenced that sputum smears for acid-fast bacilli, sputum culture, GeneXpert Mtuberculosis/RIF, and polymerase chain reaction were all positive for tuberculosis. Furthermore, multidrug-resistant Klebsiella pneumoniae and Aspergillus fumigatus were isolated in the bacterial culture of the effusion and sputum. The blood markers were as follows: White blood count: 13.67 × 10⁹/L (81.1% neutrophils and 5.6% lymphocytes); C-reactive protein: 89.54 mg/L; ESR: 34 mm/h; procalcitonin: 0.22 ng/mL. The patient's liver and kidney functions, electrolytes, myocardial enzymes, and coagulation were normal.

Imaging examinations

The chest computed tomography (CT) scan showed bilateral pulmonary infection with cavitary lesions (Figure 1A). The right lung was completely compressed and atelectatic with severe air leakage; pleural thickening of the right upper lung indicated right lung damage (Figure 1B). The coarctation of the right intercostal space is noted on the chest CT (Figure 1D). Bronchoscopy at admission (Figure 2A) and 1 mo after the anti-tuberculosis treatment showed a 5 mm fistula of the right upper bronchus (Figure 2B), along with erythema, erosion, and hyperplasia of the apical bronchus, and a small amount of necrotic material.

Figure 1 Chest computed tomography scans of patient. A: At admission and before surgery show bilateral pulmonary infection and complete compression and atelectasis of the right lung. Postoperative chest computed tomography (CT) demonstrates right lung expansion; B: Chest CT scan showing the destruction of the right upper lung; C: Both the presence of pus in the pleural cavity and iodine gauze in the emphysematous pleural space are observed. The residual cavity is eliminated after surgery; D: The coarctation of the right intercostal space is noted on chest CT. The patient’s right chest wall deformity has almost resolved, 6 months after the operation.

Figure 2 Bronchoscopic view of the right upper bronchus. A: Bronchoscopy at admission shows a 5 mm fistula (white arrows) of the right upper bronchus, along with erythema, erosion, and hyperplasia of the apical bronchus, and a small amount of necrotic material; B: Bronchoscopy is performed 1 mo after the anti-tuberculosis treatment; C: Bronchoscopy is performed 6 mo after the anti-tuberculosis treatment.

FINAL DIAGNOSIS

This patient was diagnosed with BPF, endobronchial tuberculosis, pulmonary tuberculosis, tuberculosis lung damage, and pleural empyema.

TREATMENT

The timeline of management is shown in Figure 3. Closed thoracic drainage and anti-tuberculosis therapy were conducted after the patient’s hospital admission. The patient’s anti-tuberculosis treatment program included the following medications taken once daily: Isoniazid 300 mg qd; rifampicin 450 mg qd; ethambutol 750 mg qd; levofloxacin 600 mg qd; amikacin 600 mg qd and linezolid 200 mg qd. The patient was subsequently discharged to continue treatment at home. Despite anti-tuberculosis treatment for 2 mo, the disease progressed leading to readmission. A previously installed chest tube from the initial hospitalization was removed due to a complicated pleural infection. Due to difficulty finding an appropriate location for closed drainage, the patient underwent a right open-window thoracostomy to improve fluid drainage. The 7^th and 8^th partial ribs were removed to construct a window, 10 cm in diameter. Surgery confirmed the presence of a thick pleural membrane surrounding the right lung and a 5 mm fistula with air leakage from the right upper lung. In addition, mold was found on the pleural surface (Figure 4A). To address the pleural empyema, gauzes soaked in iodine were packed into the pleural space through the window, once or twice a day after surgery. Voriconazole and intrapleural irrigation of amphotericin B were administered for antifungal treatment. Amphotericin B (10 mg) was diluted with 5% glucose solution to form a total volume of approximately 50 mL. Subsequently, the aspergillosis-infected pleura was irrigated with this solution by packing amphotericin-soaked gauze into the emphysematous space. Irrigation was performed once daily for 1 mo.

Figure 3 The timeline of treatment and procedures. TB: Tuberculosis; BPF: Bronchopleural fistula.

Figure 4 Intraoperative and postoperative findings. A: Open-window thoracostomy was performed on the patient; intraoperatively, mold was noted on the pleural surface; B: No effusions were noted in the pleural cavity and no lesions were seen on the pleural surface.

Infection was controlled remarkably after surgery, through continuous treatment with antibiotics and antifungal agents over 4 mo. The patient underwent right upper lobectomy accordingly. Intraoperatively, thick, fibrotic pleural membranes were found and decortication was conducted. Bronchial stump reinforcement was performed through the mediastinal pleura. Finally, the thoracic window was closed. In order to prevent recurrence, postoperative antifungal treatment was continued for 3 mo, and anti-tuberculosis treatment for 6 months.

OUTCOME AND FOLLOW-UP

Improvement of symptoms and postoperative examination demonstrated the positive effects of the therapeutic strategy. Repeat cultures of sputum and bronchoalveolar lavage fluid were negative. Chest CT at 6 mo after the treatment revealed diminished lung lesions. (Figure 1B). Repeat bronchoscopy also demonstrated improvement of the right upper bronchial tuberculosis and the absence of any abnormality in the middle and lower bronchus (Figure 2C). The pleural effusion were resolved and no lesions were found on the pleural surface (Figure 4B). The patient’s physical strength returned after dietary intervention. The right lung expanded well and the chest wall deformity resolved 6 mo after the operation (Figure 1C). The patient showed a favorable long-term prognosis and no evidence of recurrence at follow-up.

DISCUSSION

Many therapeutic strategies have been implemented in the treatment of BPF[5-11], but a consensus on the best treatment modality has yet to be reached. The current therapeutic options can be complementary, and the treatment needs to be individualized[12]. Herein, we described the successful treatment of tuberculous BPF through surgery. Favorable surgical outcomes for BPF depend on the selection and timing of the operation, standard preoperative anti-tuberculosis treatment, full thoracic drainage, and infection control.

Clinical treatment of tuberculous BPF complicated with multiple infections is a huge challenge. We believe that preoperative standard anti-tuberculosis treatment combined with full thoracic drainage is crucial[13,14]. For patients with Mycobacterium tuberculosis-positive sputum before surgery, a drug-resistant tuberculosis test is needed to choose effective anti-tuberculosis drugs. In our case, however, drug therapy for inflammation caused by Klebsiella pneumoniae spp. and Aspergillus fumigatus was not effective. Full drainage of the thoracic cavity was eventually achieved through open-window thoracostomy, which led to the significant improvement of chronic inflammation. Open-window thoracostomy is a simple, certain, and last resort drainage procedure for thoracic empyema[15,16]. It is the best means to drain purulent effusion caused by empyema from the pleural space and is an excellent interim treatment for BPF[17,18]. Furthermore, intrapleural irrigations of amphotericin B have been proven effective in preventing the recurrence of lung aspergillomas[19,20]. As prolonged air leaks caused by BPF create ventilatory abnormalities through the ineffective gas exchange, packing iodine-soaked gauzes into the empyema-affected pleural space through an open window can add positive intrapleural pressure during inspiration. This procedure could decrease the air leaks caused by BPF. Klebsiella pneumoniae spp. and Aspergillus fumigatus are opportunistic infections associated with immunodeficiency. Accordingly, nutritional supplementation also plays a very important role in recuperation from these infections.

The main challenge in BPF lies in closing the fistula and eliminating the cavitation. A variety of surgical and bronchoscopic strategies for treating BPF have been described, although none of these approaches has been successful or suitable for all patients. According to Li et al[10], the scope of bronchoscopy makes it difficult to treat peripheral BPF. The size of BPF > 8 mm is generally unsuitable for bronchoscopic treatment[12,21]. The degree of infection, timing of diagnosis, underlying disease, localization and the size of the fistula may be the critical factors in choosing between surgical and bronchoscopic procedures for treatment[8,22,23]. In our case, as the bronchial stump was affected by tuberculosis and the right upper lung was damaged, we did not select the minimally invasive bronchoscopic method as a treatment strategy. In a patient with lobar lung damage combined with empyema, especially in patients with BPF, aggressive radical therapy with lobectomy or thoracoplasty is necessitated[24,25]. However, the effectiveness of surgery in the treatment of drug-resistant tuberculosis remains unclear[26]. The advantages of bronchial stump reinforcement in preventing BPF are also still controversial, and no consensus has been reached on the ideal buttressing tissue to use[27-29]. Patients with empyema and bronchial tuberculosis undergoing lung resections are at increased risk for BPF recurrence. Besides, preoperative bronchoscopy is used to exclude endobronchial tuberculosis. Hence, we used the mediastinal pleura to cover the bronchial stump. However, as these procedures carries a high risk of mortality and recurrence[30], it is not universally recommended and its indications should be carefully considered. In our patient, chest CT and bronchoscopic images were reviewed regularly to assess the progression of pulmonary and bronchial lesions, preoperatively. The disease course is even more complicated for patients with tuberculous BPF. The key to the treatment of pulmonary tuberculosis complicated with BPF is to have a continual and effective anti-tuberculosis treatment. The preoperative anti-tuberculosis treatment regimen is complex. Clinicians should be ready to adjust the regimen at any time according to its therapeutic effects and adverse reactions.

CONCLUSION

In summary, the treatment of tuberculous BPF has been a challenging issue in thoracic surgery. Surgery is the modality of choice for tuberculous BPF, but it has many complications. Strict preoperative evaluation of surgical indications is required, including standard preoperative anti-tuberculosis treatment with medical therapy and full thoracic drainage to control the infection. The proper selection of patients for surgical intervention can achieve a satisfactory long-term prognosis, and the procedures are safe and efficient. Further research is required to obtain more definitive evidence.