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Mucoid impaction of a stem bronchus
Mucoid impaction of a stem bronchus Persistent atelectasis of the left lung was the chief finding in an elderly woman who had no background of chronic lung disease. At operation lower lobectomy was necessary because of irreversible parenchymal changes, but it was possible to salvage the upper lobe. Pathologically, the process was found to be mucoid impaction of the bronchi (MIB). Although this condition rarely involves an entire lung, its recognition is important because treatment with intrabronchial acetylcysteine may be definitive and surgery, if required, should be conservative.
Eugene G. Laforet, M.D., Boston and Newton Lower Falls, Mass.
I n the more than two decades since Shaw"
described and named mucoid impaction of the bronchi (MIB), the disease has gained acceptance as a legitimate if uncommon entity. Although the clinical settings in which MIB is most likely to be seen have been fairly well delineated, the basic etiology remains obscure. Classically, 2 though not necessarily," MIB occurs against a background of chronic bronchial disease (asthma, obstructive bronchitis, cystic fibrosis, or allergic bronchopulmonary aspergillosis), involves the second- or third-order bronchi, and is fostered by residence in a warm, dry climate. It is the purpose of this report to describe the occurrence of MIB involving an entire lung in an elderly New Englander with no history of bronchopulmonary disease. Case report A 69-year-old widow was admitted to Sturdy Memorial Hospital, Attleboro, Massachusetts, with a 3 month history of cough productive of yellowish sputum. The cough was persistent and unrelieved with the usual expectorants. The patient reported no hemoptysis or history of aspiration. However, she had noted mild dyspnea on From the Department of Surgery, Boston University School of Medicine, Boston, Mass., and the Thoracic Surgery Service, Newton-Wellesley Hospital, Newton Lower Falls, Mass. Received for publication March 28, 1974. Address for reprints: 2000 Washington Street, Newton Lower Falls, Mass. 02162.
exertion. The patient was a nonsmoker. On physical examination she was an elderly, thin woman who had no complaints while lying in bed. The temperature was 99.2 F., pulse 84 beats per minute, respirations 20 breaths per minute, and blood pressure 130/90 mm. Hg. Breath sounds were absent over the entire left hemithorax, with bronchial breath sounds in the hilar area. No ra.1es or wheezes were heard. The right hemithorax was unremarkable. The remainder of the physical examination was within normal limits. A chest roentgenogram showed total atelectasis of the left lung (Fig. I). Findings from the electrocardiogram were unremarkable. The hematocrit value was 41 per cent, hemoglobin 13.7 Gm. per 100 ml., and white blood count 12,300 per cubic millimeter with 43 segmented poly cells, 8 stab cells, 8 eosinophile, 30 lymphocytes, 5 atypical lymphocytes, and 6 monocytes. There were 10 to 15 white blood cells per high-power field in the urinary sediment. Electrolytes were unremarkable. Measurement of arterial blood gases showed a pH of 7.48, Po, of 59 mm. Hg, and Pea, of 32 mm. Hg. Culture and acid-fast studies of the sputum were negative. Vital capacity was 55 per cent of predicted, and forced expiratory volume at 1 second was markedly reduced. Bronchoscopy, performed on April 12, 1972, showed obstruction of the left main-stem bronchus 3 em. from the carina. No tumor was seen within the lumen of the bronchus, and no blood was noted. Washings were obtained, and all studies, including cultures and cytology, were unremarkable. Bronchial biopsy showed chronic bronchitis with many eosinophils. A bronchogram (Fig. 2) demonstrated complete obstruction of the left main-stem bronchus with collapse of the left lung. The patient was subsequently treated with intermittent positive-pressure breath0
309
The Jo urnol of
3 ]0
Lajoret
Thoracic a nd Card iovascular Surgery
Fig. 1. Preoperative chest x-ray film shows total atelectasis of the left lung and med iastinal shift to the left . Fig. 3. Anteroposterior laminagram at the 10 em. level demonstrates tot al obstruction of left mainstem bronchus.
Fig. 2. Bronchogram demonstrates abrupt "cutoff" of contrast medium in left main- stem bronchus . (Left lateral decubitus position.')
ing, heated high humidity, and chest physiotherapy, but without improvement. On April 25, 1972, the patient was transferred to Newton-Wellesley Ho spital. A laminagram (F ig. 3) showed a tapering "cut-off" of the left stem bronchus with dist al atelectasis. The patient's course remained afebrile. The most likely diagnosis was considered to be tumor involving
the left stem bronchus. On April 28, 1972, bronchoscopy was performed under general anesthesia as a preliminary to thoracotomy. The carina was sharp a nd flexible, and the right side was unremarkable. On the left , however, I em. within the lumen of the left stem bronchus and immediately below the carina, was a whitish gray , somewhat gelatinous but rubbery mass. The lesion seemed to be densely adherent to the waIls of the bronchus and could not be dislodged either with the open-end suction tip or with the forward-grasping forceps. After multiple attempts had been made with these instruments, it appeared that a small opening in the mass had been made with the aspirating tube . However , it could not be determined whether the mass was exophytic tumor or another lesion . Con sequently , left thoracotomy was undertaken . The entire left lung was found to be atelectatic. There were numerous succulent lymph nodes in the subao rtic window and surrounding the root of the lung on all sides , including the pulmonary ligament. In addition, large, firm, edematous lymph nodes, whitish on cross section , were located in the fissure between the upper a nd lower lobes. Wedge resection of a firm area in the lower lobe disclosed chronic pneumonitis. None of the lymph nodes contained tumor. The left stem bronchus was mobilized by sha rp and blunt
Volume 68 Number 2
Mucoid impaction of stem bronchus
August, 1974
3 11
dissection. Numerous lymph node s were adherent to it, and large, edematous lymph nodes were found in the subca rinal area. A long itudinal bronchotomy was done through the membranous portion of the left stem bro nchus, and a large amount
of
tena cious
InU CU S
w as
removed
by
suctioning. No tumor was seen . After protract ed suctioning and intermittent closure of the bronchotomy, it was possible to expand the upper lobe. Cons iderably more suct ion ing was required to permit expan sion of the lower lobe, and a large amount of tenacious mucus was recovered, followed eventually by th in, frankly purulent, yellowish secretion. No definite tumor was discovered, eithe r in the numerous frozen-section studies of lymph nodes and lung or by palpation. Multiple nodular densities, which suggested abscess formation, were palpable in the lower lobe. It was decided to perform left lower lobectomy since the parench ymal cha nges were considered to be irreversible and the possib ility of a distal obstructing tumor could not be excluded. The residual left upper lobe expanded readil y at the conclusion of the operation. Histologically, the resected lower lobe showed bronchial changes suggestive of asthma, including thickening of the basement membrane, muscle and mucus gland hypertrophy, and an inflammatory infiltrate that included eosinophils. There was focal acute bronchitis and obstructive bronchopneumonia. Postoperatively, the patient did welI except for the development of atrial fibrillat ion which responded to qu inidine and digoxin. She was discharged , in improved condition , on May 7, 1972, 9 days after operation. Because of an irritati ve cough, the patient was readmitted to Newton Wellesley Hospital in October of 1972, at which time a chest roentgenogram (Fig. 4) was unremarkable . Bronchoscopy, performed on Oct. 13, 1972, showed mild endobronchitis but no oth er abnormalities. The stump of the left lower lobe bronchus was un remarkable. The patient was discharged and has subsequently done well. She was free of respiratory symptoms as of March, 1974, and the chest x-ray film was unremarkable.
Discussion Although some' are loath to include MIB with the mucus-plugging complications seen in status asthmaticus, chronic bronchitis, or cystic fibrosis, it is not clear that the processes are totally unrelated. Furthermore, it is unlikely that the disease has appeared de novo in recent years. Indeed, when the emphasis is placed on the clinical and pathological findings and not on the roentgeno-
Fig. 4. Postoperative chest x-ray film.
graphic appearance, it would seem that MIB is a latter-day synonym for fibrinous, plastic, pseudomembranous, or Hoffmann's bronchitis. " However, "mucoid impaction of the bronchi" is a useful and descriptive term with a pleasing acronym . So long as the semantic proprieties are observed , the term . should have a long life. Atelectasis of an entire lung due to MIB , as indicated earlier, is distinctly unusual, although the case of Woolley" and that of Irwin and Thomas" are conspicuous exceptions . The consensus favors conservative management, reserving surgery for cases in which the diagnosis is insecure or the parenchymal changes are irreparable. In the present instance this approach made it possible to salvage an upper lobe which has continued to function well. If the proper diagnosis is suspected , vigorous therapy with intrabronchial acetylcysteine has been advocated and may prove effective even with atelectasis of an entire lung.G Because there was no history of chronic lung disease in the present case, however, the possibility of MIB was not considered. Even at the time of bronchoscopy, it was difficult to determ ine the nature of the complete bronchial obstruction visualized.
The Journal of
3 12
Laioret
Thoracic and Cardiovascular Surgery
REFERENCES Shaw, R. R.: Mucoid Impaction of the Bronchi, J. THORAC. SURG. 22: 149, 1951. 2 Urschel, H. c., Jr., Paulson, D. L., and Shaw, R. R.: Mucoid Impaction of the Bronchi, Ann. Thorac. Surg. 2: 1, 1966. 3 Tsai, S. H., and Jenne, J. W.: Mucoid Impaction of the Bronchi, Am. J. Roentgenol. Radium Ther. Nucl. Med. 96: 953, 1966.
4 Braman, S. S., and Whitcomb, M. E.: Mucoid Impaction of the Bronchus, J. A. M. A. 223: 641, 1973. 5 Woolley, P. B.: Massive Atelectasis Due to Fibrinous Bronchitis, Thorax 8: 301, 1953. 6 Irwin, R. S., and Thomas, H. M., III: Mucoid Impaction of the Bronchus: Diagnosis and Treatment, Am. Rev. Resp. Dis. 108: 955, 1973.
Eugene G. Laforet, M.D., Boston and Newton Lower Falls, Mass.
I n the more than two decades since Shaw"
described and named mucoid impaction of the bronchi (MIB), the disease has gained acceptance as a legitimate if uncommon entity. Although the clinical settings in which MIB is most likely to be seen have been fairly well delineated, the basic etiology remains obscure. Classically, 2 though not necessarily," MIB occurs against a background of chronic bronchial disease (asthma, obstructive bronchitis, cystic fibrosis, or allergic bronchopulmonary aspergillosis), involves the second- or third-order bronchi, and is fostered by residence in a warm, dry climate. It is the purpose of this report to describe the occurrence of MIB involving an entire lung in an elderly New Englander with no history of bronchopulmonary disease. Case report A 69-year-old widow was admitted to Sturdy Memorial Hospital, Attleboro, Massachusetts, with a 3 month history of cough productive of yellowish sputum. The cough was persistent and unrelieved with the usual expectorants. The patient reported no hemoptysis or history of aspiration. However, she had noted mild dyspnea on From the Department of Surgery, Boston University School of Medicine, Boston, Mass., and the Thoracic Surgery Service, Newton-Wellesley Hospital, Newton Lower Falls, Mass. Received for publication March 28, 1974. Address for reprints: 2000 Washington Street, Newton Lower Falls, Mass. 02162.
exertion. The patient was a nonsmoker. On physical examination she was an elderly, thin woman who had no complaints while lying in bed. The temperature was 99.2 F., pulse 84 beats per minute, respirations 20 breaths per minute, and blood pressure 130/90 mm. Hg. Breath sounds were absent over the entire left hemithorax, with bronchial breath sounds in the hilar area. No ra.1es or wheezes were heard. The right hemithorax was unremarkable. The remainder of the physical examination was within normal limits. A chest roentgenogram showed total atelectasis of the left lung (Fig. I). Findings from the electrocardiogram were unremarkable. The hematocrit value was 41 per cent, hemoglobin 13.7 Gm. per 100 ml., and white blood count 12,300 per cubic millimeter with 43 segmented poly cells, 8 stab cells, 8 eosinophile, 30 lymphocytes, 5 atypical lymphocytes, and 6 monocytes. There were 10 to 15 white blood cells per high-power field in the urinary sediment. Electrolytes were unremarkable. Measurement of arterial blood gases showed a pH of 7.48, Po, of 59 mm. Hg, and Pea, of 32 mm. Hg. Culture and acid-fast studies of the sputum were negative. Vital capacity was 55 per cent of predicted, and forced expiratory volume at 1 second was markedly reduced. Bronchoscopy, performed on April 12, 1972, showed obstruction of the left main-stem bronchus 3 em. from the carina. No tumor was seen within the lumen of the bronchus, and no blood was noted. Washings were obtained, and all studies, including cultures and cytology, were unremarkable. Bronchial biopsy showed chronic bronchitis with many eosinophils. A bronchogram (Fig. 2) demonstrated complete obstruction of the left main-stem bronchus with collapse of the left lung. The patient was subsequently treated with intermittent positive-pressure breath0
309
The Jo urnol of
3 ]0
Lajoret
Thoracic a nd Card iovascular Surgery
Fig. 1. Preoperative chest x-ray film shows total atelectasis of the left lung and med iastinal shift to the left . Fig. 3. Anteroposterior laminagram at the 10 em. level demonstrates tot al obstruction of left mainstem bronchus.
Fig. 2. Bronchogram demonstrates abrupt "cutoff" of contrast medium in left main- stem bronchus . (Left lateral decubitus position.')
ing, heated high humidity, and chest physiotherapy, but without improvement. On April 25, 1972, the patient was transferred to Newton-Wellesley Ho spital. A laminagram (F ig. 3) showed a tapering "cut-off" of the left stem bronchus with dist al atelectasis. The patient's course remained afebrile. The most likely diagnosis was considered to be tumor involving
the left stem bronchus. On April 28, 1972, bronchoscopy was performed under general anesthesia as a preliminary to thoracotomy. The carina was sharp a nd flexible, and the right side was unremarkable. On the left , however, I em. within the lumen of the left stem bronchus and immediately below the carina, was a whitish gray , somewhat gelatinous but rubbery mass. The lesion seemed to be densely adherent to the waIls of the bronchus and could not be dislodged either with the open-end suction tip or with the forward-grasping forceps. After multiple attempts had been made with these instruments, it appeared that a small opening in the mass had been made with the aspirating tube . However , it could not be determined whether the mass was exophytic tumor or another lesion . Con sequently , left thoracotomy was undertaken . The entire left lung was found to be atelectatic. There were numerous succulent lymph nodes in the subao rtic window and surrounding the root of the lung on all sides , including the pulmonary ligament. In addition, large, firm, edematous lymph nodes, whitish on cross section , were located in the fissure between the upper a nd lower lobes. Wedge resection of a firm area in the lower lobe disclosed chronic pneumonitis. None of the lymph nodes contained tumor. The left stem bronchus was mobilized by sha rp and blunt
Volume 68 Number 2
Mucoid impaction of stem bronchus
August, 1974
3 11
dissection. Numerous lymph node s were adherent to it, and large, edematous lymph nodes were found in the subca rinal area. A long itudinal bronchotomy was done through the membranous portion of the left stem bro nchus, and a large amount
of
tena cious
InU CU S
w as
removed
by
suctioning. No tumor was seen . After protract ed suctioning and intermittent closure of the bronchotomy, it was possible to expand the upper lobe. Cons iderably more suct ion ing was required to permit expan sion of the lower lobe, and a large amount of tenacious mucus was recovered, followed eventually by th in, frankly purulent, yellowish secretion. No definite tumor was discovered, eithe r in the numerous frozen-section studies of lymph nodes and lung or by palpation. Multiple nodular densities, which suggested abscess formation, were palpable in the lower lobe. It was decided to perform left lower lobectomy since the parench ymal cha nges were considered to be irreversible and the possib ility of a distal obstructing tumor could not be excluded. The residual left upper lobe expanded readil y at the conclusion of the operation. Histologically, the resected lower lobe showed bronchial changes suggestive of asthma, including thickening of the basement membrane, muscle and mucus gland hypertrophy, and an inflammatory infiltrate that included eosinophils. There was focal acute bronchitis and obstructive bronchopneumonia. Postoperatively, the patient did welI except for the development of atrial fibrillat ion which responded to qu inidine and digoxin. She was discharged , in improved condition , on May 7, 1972, 9 days after operation. Because of an irritati ve cough, the patient was readmitted to Newton Wellesley Hospital in October of 1972, at which time a chest roentgenogram (Fig. 4) was unremarkable . Bronchoscopy, performed on Oct. 13, 1972, showed mild endobronchitis but no oth er abnormalities. The stump of the left lower lobe bronchus was un remarkable. The patient was discharged and has subsequently done well. She was free of respiratory symptoms as of March, 1974, and the chest x-ray film was unremarkable.
Discussion Although some' are loath to include MIB with the mucus-plugging complications seen in status asthmaticus, chronic bronchitis, or cystic fibrosis, it is not clear that the processes are totally unrelated. Furthermore, it is unlikely that the disease has appeared de novo in recent years. Indeed, when the emphasis is placed on the clinical and pathological findings and not on the roentgeno-
Fig. 4. Postoperative chest x-ray film.
graphic appearance, it would seem that MIB is a latter-day synonym for fibrinous, plastic, pseudomembranous, or Hoffmann's bronchitis. " However, "mucoid impaction of the bronchi" is a useful and descriptive term with a pleasing acronym . So long as the semantic proprieties are observed , the term . should have a long life. Atelectasis of an entire lung due to MIB , as indicated earlier, is distinctly unusual, although the case of Woolley" and that of Irwin and Thomas" are conspicuous exceptions . The consensus favors conservative management, reserving surgery for cases in which the diagnosis is insecure or the parenchymal changes are irreparable. In the present instance this approach made it possible to salvage an upper lobe which has continued to function well. If the proper diagnosis is suspected , vigorous therapy with intrabronchial acetylcysteine has been advocated and may prove effective even with atelectasis of an entire lung.G Because there was no history of chronic lung disease in the present case, however, the possibility of MIB was not considered. Even at the time of bronchoscopy, it was difficult to determ ine the nature of the complete bronchial obstruction visualized.
The Journal of
3 12
Laioret
Thoracic and Cardiovascular Surgery
REFERENCES Shaw, R. R.: Mucoid Impaction of the Bronchi, J. THORAC. SURG. 22: 149, 1951. 2 Urschel, H. c., Jr., Paulson, D. L., and Shaw, R. R.: Mucoid Impaction of the Bronchi, Ann. Thorac. Surg. 2: 1, 1966. 3 Tsai, S. H., and Jenne, J. W.: Mucoid Impaction of the Bronchi, Am. J. Roentgenol. Radium Ther. Nucl. Med. 96: 953, 1966.
4 Braman, S. S., and Whitcomb, M. E.: Mucoid Impaction of the Bronchus, J. A. M. A. 223: 641, 1973. 5 Woolley, P. B.: Massive Atelectasis Due to Fibrinous Bronchitis, Thorax 8: 301, 1953. 6 Irwin, R. S., and Thomas, H. M., III: Mucoid Impaction of the Bronchus: Diagnosis and Treatment, Am. Rev. Resp. Dis. 108: 955, 1973.