Successful management of fistulous empyema caused by Mycobacterium avium complex in an advanced-age patient: A case report

Abstract

Herein, we report the case of an 87-year-old woman who presented with acute chest pain, fever, and cough. Imaging revealed a right pneumothorax, pleural effusion, and bronchiectasis. Pleural fluid was exudative with elevated adenosine deaminase levels, and Mycobacterium avium complex (MAC) was confirmed. Thoracoscopic plication and empyema cavity curettage were performed. Postoperatively, clarithromycin, rifampicin, ethambutol, and amikacin were initiated, leading to clinical improvement, smear and culture negativity, and discharge.

Pleuritis caused by nontuberculous mycobacteria (NTM) is rare, occurring in only 1.4% of patients with NTM pulmonary disease; however, pneumothorax has been reported in 41% of these patients. NTM pleural disease with empyema is associated with a poor prognosis, with a 1-year mortality rate of 14–37%. In our report, early diagnosis enabled timely surgical and pharmacological intervention. This report highlights that even in advanced-age patients with preserved performance status, early multidisciplinary management may achieve favorable outcomes in MAC-associated pneumothorax and pleuritis.

1. Introduction

Nontuberculous mycobacteria (NTM) cause infectious diseases, and chronic pulmonary disease is the most common clinical manifestation [1]. Pleuritis caused by NTM is a rare condition with high reported mortality rates [2]. The incidence of pleuritis among patients with NTM pulmonary disease is reportedly as low as 1.4% [3]. In contrast, 41% of patients who developed pleuritis had concomitant pneumothorax [2]. This proportion is relatively high, and attention should be paid to the possibility of pneumothorax in patients with NTM who present with pleuritis. Although surgery is considered an adjunctive option for selected patients with NTM pulmonary disease, the optimal timing of surgical intervention remains unclear.

This report presents a valuable case of symptomatic improvement achieved through thoracoscopic surgery and pharmacotherapy in an advanced-age female patient with pleuritis caused by NTM.

2. Case presentation

The patient was an 87-year-old woman who presented to our hospital with a chief complaint of sudden-onset chest pain. The patient reported fever and cough since the day before presentation.

The patient had no history of smoking or alcohol consumption. The patient had hypertension and was taking antihypertensive medications.

On examination, her body temperature was 38.2 °C, and oxygen saturation (SpO₂) was 94% under 3 L/min oxygen supplementation. On auscultation of both lungs, the breathing sounds were decreased at the base of the right lung. No positive signs were observed in the examinations of other systems.

Initial laboratory investigations (Table 1) revealed the following: Blood tests revealed an elevated white blood cell count of 9970/μL, hemoglobin level of 11.2 g/dL, platelet count of 24.6 × 10⁴/μL, and C-reactive protein (CRP) level of 4.16 mg/dL, suggesting significant inflammation. Electrolyte analysis revealed a sodium level of 135 mEq/L and potassium level of 3.7 mEq/L. The creatinine level was 0.61 mg/dL, indicating normal renal function.

Table 1.

Laboratory data on admission.

Biochemistry			Hematology
TP	7.8	g/dL	WBC	9970	/μL	PT	85.7	%
Alb	2.8	g/dL	Seg	88.5	%	APTT	25.0	s
T-Bil	0.73	mg/dL	Eosin	0.0	%	Fibrinogen	504.4	mg/dL
AST	26	U/L	Baso	0.5	%
ALT	11	U/L	Lymph	8.0	%
LDH	188	U/L	RBC	342 × 104	/μL
γ-GT	12	U/L	Hb	11.2	g/dL
BUN	4.4	mg/dL	Ht	33.7	%
Cr	0.61	mg/dL	Plt	24.6 × 104	/μL
Na	135	mEq/L
K	3.7	mEq/L
Cl	101	mEq/L
CRP	4.16	mg/dL

Abbreviations.

TP, total protein; Alb, albumin; T-Bil, total bilirubin; AST, aspartate aminotransferase; ALT, alanine aminotransferase; LDH, lactate dehydrogenase; γ-GT, gamma-glutamyl transferase; BUN, blood urea nitrogen; Cr, creatinine; Na, sodium; K, potassium; Cl, chloride; CRP, C-reactive protein; WBC, white blood cell count; Seg, segmented neutrophils; Eosin, eosinophils; Baso, basophils; Lymph, lymphocytes; RBC, red blood cell count; Hb, hemoglobin; Ht, hematocrit; Plt, platelet count; PT, prothrombin time; APTT, activated partial thromboplastin time; Fibrinogen, fibrinogen.

Chest radiography revealed pneumothorax of the right lung (Fig. 1).

Fig. 1.

Chest radiograph at admission. Chest radiograph showing right pneumothorax with right lung collapse.

On admission, chest computed tomography (CT) revealed a right-sided pneumothorax and pleural effusion (Fig. 2). Additional findings included a cavitary lesion, bronchial wall thickening, ground-glass opacities, and centrilobular nodules in both lungs.

Fig. 2.

Chest CT findings at admission. (A–C) Chest computed tomography (CT) showing pleural effusion, pneumothorax, infiltrative shadows, and cavitary lung lesion (arrow).

Chest CT performed at another institution 7 years before admission demonstrated bronchiectasis and nodular lesions in the right upper lobe (segments S2, S4, and S5) and right lower lobe (segments S8, S9, and S10). Similar findings were observed in the left lung, involving the lingular segments (S4 and S5) and the lower lobe (segments S6 and S10), indicating chronic bronchiectatic and nodular changes distributed across multiple lung segments (Fig. 3).

Fig. 3.

Previous CT findings 7 years before admission. (A, B) Chest computed tomography (CT) performed at another institution 7 years before admission showing bronchiectasis and nodular lesions in the right upper lobe (segments S2, S4, and S5) and right lower lobe (segments S8, S9, and S10), indicating chronic bronchiectatic and nodular changes distributed across multiple lung segments.

Analysis of the pleural effusion revealed a slightly bloody appearance and specific gravity of 1.032. However, the pH could not be determined. The lactate dehydrogenase level was elevated to 1520 U/L, and the total protein level was 4.6 g/dL. The glucose and total cholesterol concentrations in the fluid were 85 mg/dL and 68 mg/dL, respectively. The carcinoembryonic antigen level was mildly elevated at 7.4 ng/mL, and the adenosine deaminase level was significantly increased at 62.4 U/L. The pleural fluid white blood cell count was 20.41 × 10²/μL and the red blood cell count was 1.2 × 10³/μL. Differential white blood cell counts revealed 67.5% segmented neutrophils, 1.0% eosinophils, 0.5% basophils, 28.0% lymphocytes, and 3.0% macrophages.

Acid-fast bacilli were detected via fluorescent staining of pleural fluid collected on day 1 of hospitalization, and polymerase chain reaction (PCR) testing for Mycobacterium avium was positive on day 2, whereas PCR testing for Mycobacterium tuberculosis was negative. Subsequent mycobacterial culture of the pleural fluid yielded M. avium and did not yield M. tuberculosis. Bacterial culture of the pleural fluid was negative, and pleural fluid cytology revealed no malignant cells. In addition, the sputum smear was positive for acid-fast bacilli, and sputum cultures yielded M. avium.

3. Clinical course

On day 1 of hospitalization, a chest drain was inserted, which revealed a large volume of pleural effusion; however, a persistent air leak was noted. On day 5, chest CT revealed a leak in segment 9 (S9) of the right lung, leading to the diagnosis of fistulous empyema (Fig. 4). On day 7, the patient underwent thoracoscopic right lung plication and empyema cavity curettage.

Fig. 4.

Leak point identified on CT on day 5. Chest computed tomography (CT) on day 5 showing a leak point in segment 9 (S9) of the right lung (arrow: leak point).

4. Intraoperative findings

Thoracoscopic examination revealed dense adhesions between the right lower lobe, mainly involving segment S9, and the chest wall. A persistent air leak was identified in the suspected fistula (Fig. 5). Subcutaneous fat was used for filling, and an intercostal muscle flap was sutured into position. A leak test confirmed the absence of significant air leakage, and the wound was closed with a chest drain.

Fig. 5.

Intraoperative finding of pulmonary fistula. Intraoperative photograph revealing the right lower lobe (arrow: pulmonary fistula).

5. Postoperative treatment and outcome

Based on the clinical and laboratory findings, clarithromycin (800 mg daily), rifampicin (300 mg daily), ethambutol (500 mg daily), and amikacin (400 mg three times weekly) were initiated on day 8. Following the commencement of treatment, the patient exhibited defervescence, and inflammatory marker levels showed a declining trend.

On day 11, the chest drain was successfully removed.

On day 70, the sputum smear confirmed the absence of bacilli. Subsequent cultures were negative.

The patient achieved significant clinical improvement and was discharged on day 76.

6. Discussion

We encountered a case of pneumothorax and empyema caused by MAC.

In this report, MAC infection was promptly confirmed via pleural fluid polymerase chain reaction and culture, and a review of prior imaging revealed preexisting NTM pulmonary lesions. This case report will facilitate early diagnosis and interventions. Previous studies have indicated that NTM complicated by empyema is associated with a poor prognosis, with a one-year mortality rate of 14–37% [4,5]. This poor outcome is thought to be due to several factors, including delayed diagnosis and underlying comorbidities. Previous studies have emphasized the importance of early diagnosis and immediate treatment [5]. In the present case, the diagnosis of NTM infection was established relatively early, after admission. A comparison with past imaging findings plays a crucial role in prompting the consideration of this disease.

A previous systematic review reported that patients with NTM-related pleural disease ranged in age from 9 to 87 years [2]. Based on the previously accessible surgically treated cases identified in our literature search (Table 2), this patient may represent one of the oldest reported patients to undergo surgical treatment for NTM pleuritis/empyema.

Table 2.

Previously accessible surgically treated cases of nontuberculous mycobacterial pleuritis/empyema identified through our literature search.

Study	Year	Age	NTM species	Surgery	Outcome
Hsieh et al. [6]	2008	53	M. chelonae	Thoracotomy with decortication and wedge resection of the right middle lung	Improved
Jo et al. [7]	2012	57	M. abscessus	Percutaneous tube drainage followed by right upper lobectomy	Improved
DeLeon et al. [8]	2014	77	MAC	Thoracotomy and decortication	Improved
Kadota et al. [9]	2019	63	M. abscessus subsp. abscessus	Thoracoscopic curettage and drainage	Improved
Goto et al. [10]	2020	75	M. abscessus subsp. abscessus	Decortication and fistulectomy	Improved
Wen et al. [11]	2020	26	Unidentified strain	Decortication of pleural fibreboard	Improved
Wen et al. [11]	2020	63	M. intracellulare	Sinus tract resection	Improved

Abbreviations: NTM, nontuberculous mycobacteria; MAC, Mycobacterium avium complex.

In Jo et al., the causative organism was reported as M. abscessus, but the subspecies was not specified in the accessible report.

Previous cases have included thoracotomy with decortication and wedge resection [6], right upper lobectomy after percutaneous drainage [7], thoracotomy and decortication [8], thoracoscopic curettage followed by drainage [9], decortication and fistulectomy [10], and adjuvant surgery in two patients [11]. These reports suggest that surgery has been selected for source control and management of persistent air leakage or bronchopleural communication.

In the present case, favorable clinical improvement was achieved with a combination of surgical intervention and chemotherapy. These findings suggest that combined surgical and antimicrobial treatment may be feasible even in advanced-age patients when the performance status is preserved and adequate source control can be achieved.

Kuo et al. reported that the preoperative antibiotic duration varies widely and that early surgery appears feasible and potentially beneficial, even in extensive NTM pulmonary disease [12].

In the present advanced-age patient, we considered that a prolonged clinical course could lead to deterioration in the general condition and progression of pleural adhesions, thereby increasing surgical difficulty and perioperative risk, and potentially narrowing the window for definitive source control. Given the suspected fistulous pathology with persistent air leak and empyema, we opted for early surgical source control followed by intensified antimicrobial therapy, which resulted in favorable clinical improvement.

Currently, no established treatment recommendations specifically address NTM pleuritis complicated by empyema or pneumothorax. The 2020 ATS/ERS/ESCMID/IDSA guidelines [13] do not provide disease-specific guidelines for pleural involvement. However, these guidelines consistently recommend intensified combination therapy for severe forms of pulmonary MAC disease, including fibrocavitary, cavitary nodular bronchiectatic, and severe nodular bronchiectatic diseases. In such cases, the addition of aminoglycosides (amikacin or streptomycin) to the standard macrolide-based regimen is recommended. In the present case, the patient exhibited cavitary lung lesions accompanied by bronchopleural fistula formation, pneumothorax, and empyema, indicating severe and progressive MAC infection. Although specific treatment guidelines for MAC pleuritis are lacking, the severity of pulmonary disease in this patient was considered consistent with that of cavitary MAC disease. Therefore, we selected a four-drug regimen consisting of clarithromycin, ethambutol, rifampicin, and amikacin, in accordance with the existing guidelines for severe pulmonary MAC disease. This approach converts the smear to a negative result. These findings suggest that a four-drug regimen may be effective for treating pulmonary MAC disease complicated by pneumothorax or pleuritis.

7. Conclusions

This report presents a rare instance of fistulous empyema associated with nontuberculous mycobacterial infection, in which early diagnosis and multidisciplinary treatment, including thoracoscopic surgery, led to symptom improvement. These findings suggest that early intervention, including surgical treatment, may contribute to improved outcomes, even in advanced-age patients.

CRediT authorship contribution statement

Yusuke Kuze: Writing – original draft. Yuri Enomoto: Writing – review & editing. Daisuke Sekinada: Writing – review & editing. Yoshio Nakano: Writing – review & editing. Gen Masuda: Writing – review & editing. Koji Nishida: Writing – review & editing. Norio Okamoto: Writing – review & editing. Iwao Gohma: Writing – review & editing. Hiroyuki Fukuda: Writing – review & editing. Yoko Yamamoto: Writing – review & editing. Naoki Ikeda: Writing – review & editing.

Ethics statement

Written informed consent for publication of this manuscript and accompanying images was obtained from the patient in accordance with institutional requirements.

Declaration of competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.