Bronchogenic Cysts of the Mediastinum in Infancy

Transcription

1 Bronchogenic Cysts of the Mediastinum in Infancy A Cause of Acute Respiratory Distress Shakeab Alshabkhoun, M.D.,* George W. B. Starkey, M.D.,? and Russell A. Asnes, M.D. A lthough uncommon, bronchogenic cysts of the mediastinum in infancy are an important group of lesions. They produce severe and recurrent attacks of respiratory distress that may end fatally if the cause is not recognized (see Table 1). Excisional surgery is curative, but diagnosis may be elusive. Many of the features of this condition are illustrated by the two cases reported below. CASE REPORTS CASE 1 A 12-week-old Negro male was well until one week prior to admission, when he developed cough, fever, and respiratory distress. On physical examination he was well developed and well nourished. Temperature was 100 F. rectally, and respirations were fifty per minute. There was flaring of the ala nasi, chest retraction, diminished breath sounds over the left chest, and bilateral, moist rales and wheezing. The heart was unremarkable. The leukocyte count was 15,800 with normal differential, the hematocrit 36%, the urinalysis normal, and the intermediate-strength PPD test negative. Cultures of laryngeal and tracheal aspirates revealed normal flora. The initial chest x-ray (Fig. 1) showed a hyperaerated left lung and a mediastinal shift to the right. Hospital Course. A diagnosis of bronchiolitis was entertained, and the patient was treated with oxygen, mist, and decongestants. However, x-rays continued to show overdistension of the left lung. A bronchoscopy was performed and disclosed generalized reddening of the bronchial mucosa and a slitlike narrowing of the left main-stem bronchus immediately distal to the carina. A barium swallow revealed slight compression of the midesophagus along the left lateral border below the level of the carina. There was no demonstrable esophageal fistula. A scheduled bronchogram was postponed because the patient suddenly developed tachypnea at the rate of 70 respirations per minute, abdominal distension, and marked intercostal retractions. Moist rales, decreased breath sounds, and wheezes were heard over the left chest. An emergency bronchoscopy was performed, and thick, tenacious secretions were aspirated from the trachea and left main-stem bronchus. A tracheostomy was done which relieved the acute From the Thoracic Surgery Service, Boston City Hospital, Boston, Mass. *Former Resident ( ), Thoracic Surgery Service, Boston City Hospital. Present address: Mount Sinai Hospital Medical Center, Chicago, Ill. TVisiting staff (1952- ), Thoracic Surgery Service, Boston City Hospital; Assistant Clinical professor of Surgery, Harvard Medical School. Present address: Lahey Clinic, Boston. 532 THE ANNALS OF THORACIC SURGERY

2 Bronchogenic Cysts in Infancy FIG. 1. Case 1. Chest x-ray (during barium swallow) showing mediastinal shift to the right and hyperaeration of left lung. distress. A bronchogram demonstrated a marked narrowing of the left main-stem bronchus; there were collections of dye in the subcarinal region to the left of the midline (Fig. 2). The areas occupied by the dye appeared to be lobulated and smooth, measuring 1.5 cm. in diameter. Exploratory left tlioracotomy revealed two lobulated cysts in the mediastinuin attached to the undersurface of the left main-stem bronchus and filled with white mucoid material. Because the patient developed bradycardia, only one cyst was rapidly removed; the second one was evacuated by needle aspirations. The left pleural space was drained, and the chest was closed. Within 24 FIG. 2. Case 1. Uronchograrn on the first hospital admission. Note the narrowing of the proximal left main-stem bronchus and dye filling multiloculated cyst in the subcarinal area. VOL. 4, NO. 6, DEC.,

3 ALSHABKHOUN, STARKEY, AND ASNES FIG. 3. Case 1. Bronchogram on the second hospital admission disclosing widened carina and seuerely narrowed left main-stem bronchus. hours there was a dramatic improvernent in the patient s condition, and by the third day his respirations were normal. The tracheostomy tube was removed early, and the patient was discharged on the tenth postoperative day. The chest x-ray on discharge was essentially normal. The histological examination of the operative specimen showed a cyst lined by ciliated columnar epithelium, a finding compatible with a bronchogenic cyst. Second Hospztal Admission. The patient did well for four months, but at the age of seven months he once again developed respiratory distress. Physical examination showed his weight to be 14 pounds, pulse rate 120, and respirations sixty per minute. He had wheeling and intercostal retractions; the breath sounds were diminished over the left chest. Chest x-ray again showed a hyperaerated left lung and a marked mediastinal shift to the right. A bronchogram revealed widening of the carina and severe narrowing of the left main-stem bronchus (Fig. 3). At a second left thoracotomy, a tense, 2 cm. bronchogenic cyst was found compressing the left main-stem bronchus. This was the cyst that had only been evacuated by needle aspiration during the first operation. The cyst was excised, and the fistula to the left bronchus was closed. The postoperative course was uneventful. Two years later the patient was asymptomatic, and his chest x-ray was normal. CASE 2 An 8-day-old Negro male was admitted in acute respiratory distress. On the day of admission the mother noted that the child s color was dusky and that his breathing was difficult. Physical examination revealed a cyanotic infant in acute respiratory distress. His pulse was 140 per minute, respirations seventy per minute, and temperature 98 F. rectally. There were intercostal and subcostal retractions and bilateral wheezing. The remainder of the examination was unremarkable. Chest x-ray revealed overdistension of the left lung, collapse of the right upper lobe, and a mediastinal shift to the right (Fig. 4). A barium swallow and bronchogram were interpreted as normal except for incomplete filling of the 534 THE ANNALS OF THORACIC SURGERY

4 Bronchogenic Cysts in Infancy FIG. 4. Case 2. Chest x-ray on admission revealing overdistended left lung with herniation into the right chest and mediastinal shift. right upper-lobe bronchus. The patient improved on mist, oxygen, penicillin, and streptomycin and was discharged home on the eighteenth hospital day. He returned to the hospital at the age of 12 weeks with persistent cough and respiratory distress. Physical examination revealed a normal temperature, a pulse rate of 180, and respirations sixty per minute. There was cyanosis, chest retraction, wheezing on the left side, and diminished breath sounds over the right upper chest. The remainder of the physical examination was negative. A chest x-ray revealed a hyperaerated left lung, collapse of the right upper lobe, and a mediastinal shift to the right. The patient was treated with oxygen, mist, and antibiotics; however, the respiratory distress progressed. A bronchoscopy was done, and a large amount of thick mucoid material was aspirated from the left main-stem bronchus. Twenty-four hours later he had a sudden respiratory arrest and died. At autopsy a 3 x 3 x 1.5 cm. noncommunicating bronchogenic cyst was found in the subcarinal area compressing the left main-stem bronchus (Fig. 5). The cyst contained thick greyish fluid and was lined with ciliated columnar epithelium. There were several blebs over the left lung, pneumonic infiltration in the right lower lobe, and collapse of the right middle lobe and left lower lobe. No other significant findings were noted. DISCUSSION Bronchogenic cysts result from an abnormal budding or branching of the tracheobronchial tree. The cyst may be joined to the tracheobronchial tree by a fistula tract or by a fibrous band. The cysts are thin walled, single or multiple, and lined by ciliated columnar epithelium. They contain mucoid material, desquamated epithelial cells, or cartilage [4, 16, 181. Cysts that produce symptoms of acute respiratory distress are usually paratracheal or subcarinal in their location (Table 1). Direct VOL. 4, NO. 6, DEC.,

5 TABLE 1. CASE REPORTS IN THE LITERATURE OF MEDIASTINAL BRONCHOGENIC CYSTS IN INFANCY AND EARLY CHILDHOOD Author & Year Age, Race, & Sex Signs & Symptoms Time of Diagnosis Pathology Blackader & Evans [51, 1911 Mixter & Stewart [211, 1929 Alford [31, 1937 Johnson [161, 1938 Wyllie & Pilcher [29], 1943 Carlson [91, 1943 Tucker [261, 1946 Marshall & Cookson 1191, 1947 Ma-iera [18], mo., white, M 3 mo., white, F 7 mo., white, F 7 yr., white, F 18 mo. 8 mo., M 3 mo., M 7 mo., white, F 9 mo., F Episodes of respiratory distress and cy anosis Episodes of wheezing and cyanosis Bilateral emphysema and terminal pneumonia Noisy and labored respirations since birth accompanied by episodes of cyanosis Dyspnea, respiratory wheezes, and spasmodic cough Respiratory distress Respiratory distress Episodes of respiratory distress, cough, and stridor Routs of dyspnea and cyanosis; frequent respiratory infections since birth Bronchogenic cyst Bronchogenic cyst communi- Bronchogenic cyst cating with the trachea Bronchogenic cyst, subcarinal area Bronchogenic cyst, subcarinal area, pressing on the left bronchus Bronchogenic cyst compressing the carina Bronchogenic cyst, subcarinal area Bronchogenic cyst, subcarinal area Bronchogenic cyst in mediastinum

6 TABLE 1 (Continued) Age, Race, Time of Author & Year & Sex Signs & Symptoms Diagnosis Pathology Exalto & Waldeck [121, 6 yr., F Episodes of dyspnea and cyanosis; 1949 chest film showed a mass compressing the trachea and right bronchus Adams [ll, wk., F Episodes of grunting respirations, dyspnea, cyanosis, and chest retraction since birth Williams [271, mo., white, F Intermittent dry cough and wheezing since the first few days of life; suprasternal and superclavicular retraction Smid et al. [251, mo. white, F Noisy chest rattle on inspiration Opsahl & Berman [22], 1962 Hurwitz et al. [151, 1966 since 2 wk. 3 wk., white, F Respiratory wheezing, fever, and dyspnea 3 mo., white, M Respiratory distress, chest retraction Bronchogenic cyst Operation Bronchogenic cyst compressing left bronchus and communicating with bronchial lumen Operation Bronchogenic cyst compressing left lung Operation Bronchogenic cyst, subcarinal area Operation Bronchogenic cyst Operation Bronchogenic cyst Reported nine cases of bronchogenic cysts; this is the only case in infancy.

7 ALSHABKHOUN, STARKEY, AND ASNES FIG. 5. Case 2. The chest organs from the posterior aspect as seen at autopsy. pressure of such a cyst on soft airway tubes in an infant rnay easily produce obstruction, while impingement of the cyst on either bronchus rnay result in partial expiratory obstruction with air trapping. This air trapping leads to overdistension, subsequent mediastinal shift, and often fatal cardiorespiratory distress (Fig. 6). In the presence of a bronchial fistula the cyst may empty its viscid contents into the bronchial lumen, producing an intrabronchial obstruction. Symptoms may appear early in infancy and consist of periodic episodes of progressive dyspnea, respiratory wheezes, and cyanosis. The symptoms may be aggravated by crying, feeding, or upper respiratory infection [l, 2, 151. The clinical course of this disease may be rapid, progressive deterioration, ending with death. The majority of early reported cases were diagnosed at autopsy (see Table 1). Cysts that do not cause symptoms in infancy may be found later in life on routine chest x-ray or incidentally at autopsy. Chest x-rays in such patients may show overdistension of one lung, mediastinal shift, and atelectasis [ 1, 15, 19, 203. Bronchoscopy may reveal widening of the carina, narrowing of one of the main-stem bronchi, and presence of thick mucoid material [15, 251. A bronchogram usually shows widening of the carina and narrowing of one of the main-stem bronchi (see Fig. 3). If a bronchial fistula is present, the cyst may be outlined by the contrast medium 538 THE ANNALS OF THORACIC SURGERY

8 Bronchogenic Cysts in Infancy FIG. 6. Mechanism of air trapping by bronchogenic cysts of the mediastinum during inspiration and expiration. (see Fig. 2). An esophagogram may show an external filling defect at the level of the carina [ll, 14, 201. The diagnosis of bronchogenic cyst should be considered in any infant with respiratory distress and unilateral overdistension of the lung. Other entities that may produce the same clinical picture are listed in the tabulation below Diflerential Diagnosis of Bronchogenic Mediastinal Cysts Aspiration of foreign body Chondromalacia [ 101 Idiopathic congenital lobar emphysema [6, 20, 28, 301 Postpneumonic pneumatocele Lung agenesis [24] Agenesis of the diaphragm or of one leaf of the diaphragm [241 Enterogenous cyst and diverticulum of the esophagus Bronchial asthma Congenital pulmonary cyst Bronchiolitis Mediastinal teratoma [24] Tracheoesophageal fistula [24] VOL. 4, NO. 6, DEC.,

9 ALSHABKHOUN, STARKEY, AND ASNES 13. Cardiovascular anomalies producing compression of the trachea or main-stem bronchi 14. Tension pneumothorax 15. Swyer-James syndrome [23, Tuberculous mediastinal adenopathy The ideal treatment of bronchogenic cyst is its total excision. Partial removal or needle aspiration may result in recurrence, as happened in Case 1. Tracheostomy is a lifesaving operation in the acute respiratory phase of this disease [15]. Discontinuation of the tracheostomy in a patient who has not had the cyst excised may result in recurrence of respiratory distress, as in Case 1 [15]. Pulmonary resection is not needed to cure these patients [15]. During surgical exploration a search should be made for cardiovascular anomalies. SUMMARY Two infants with acute respiratory distress produced by bronchogenic mediastinal cysts are presented. One patient s cyst communicated with the bronchus, while the second patient s did not. The clinical features were similar in that each had increasing dyspnea, intercostal retraction, and overdistension of one lung with a mediastinal shift. The diagnostic workup for bronchogenic cysts should include chest x-ray, bronchoscopy, bronchogram, and esophagogram. Tracheostomy can be a lifesaving procedure, but recurrence of severe dyspnea may follow removal of the tracheostomy tube in patients who have not had an excision of the cyst. Total excision of the cyst is urgent once the diagnosis is made. Incomplete removal or needle aspiration of the cyst may be followed by recurrence. REFERENCES 1. Adams, F. H. Unusual case of bronchiogenic lung cyst simulating dextrocardia. J. Pediat. 39:483, Adams, W. E., and Thornton, T. F. Bronchiogenic cysts of the mediastinum. J. Thorac. Surg. 12:503, Alford, J. E. Congenital bronchogenic cyst of the mediastinum. Arch. Path. 23:296, Arey, L. B. Developmental Anatomy (7th ed.). Philadelphia: Saunders, Blackader, A. D., and Evans, D. J. A case of mediastinal cyst producing compression of the trachea ending fatally in an infant of nine months old. Arch. Pediat. 28: 194, THE ANNALS OF THORACIC SURGERY

10 Bronchogenic Cysts in Infancy 6. Bolande, R. B., Scheider, A. F., and Boggs, J. D. Infantile lobar emphysema. Arch. Path. 61:289, Bradford, M. C., Mohan, H. W., and Grow, J. B. Mediastinal cysts and tumors. Surg. Gynec. Obstet. 85:467, Brown, R. K. The diagnosis and treatment of bronchiogenic cysts of the mediastinum. J. Thorac. Surg. 13:84, Carlson, H. A. Congenital cysts of the mediastinum. J. Thorac. Surg. 12: 376, Cox, W. L., Jr., and Shaw, R. R. Congenital chondromalasia of the trachea. J. Tlzorac. Cardiov. Swg. 401: 1032, Davis, J. G., and Simonton, J. H. Mediastinal carinal bronchiogenic cysts. Radiology 67:391, Exalto, J., and Waldeck, K. Bronchiogenic cyst of the mediastinum. J. Thorac. Surg. 18:132, Greenfield, J. Bronchial adenoma within the wall of a broncliogenic cyst: Report of a case. J. Thorac. Cardiov. Surg. 49:395, Hope, W. J. Radiological diagnosis of mediastinal masses in infants and children. Radiol. Clin. N. Arner. 1:17, Hurwitz, A., Conrad, R., Selvage, I. L., Jr., and Orbeton, E. A. Hypertrophic lobar emphysema secondary to a paratracheal cyst in an infant. J. Thorac. Cardiov. Surg. 51:412, Johnson, L. Congenital ciliated columnar epithelium cysts of the mediastinum. Amer. J. Dis. Child. 56:313, Laipply, T. C. Cysts and cystic tumors of the mediastinum. Arch. Path. 39: 153, Maier, H. C. Bronchiogenic cysts of the mediastinum. Ann. Surg. 127:476, Marshall, P. C., and Cookson, H. A. Report of a case of tracheo-bronchial cyst. Lancet 1:305, Massachusetts General Hospital. Case record New Eng. J. Med. 271:100, Mixter, C. G., and Stewart, C. Congenital mediastinal cysts of gastrogenic and bronchogenic origin. Ann. Surg. 714:90, Opsahl, T., and Berman, E. J. Bronchiogenic mediastinal cysts in infants: Case report and review of the literature. Pediatrics 30:372, Rakower, J., and Moran, E. Unilateral hyperlucent lung (Swyer-James syndrome). Amer. J. Med. 33:864, Schaffer, A..J. Diseases of the Newborn (2d ed.). Philadelphia: Saunders, Smid, A. C., Ellis, F. H., Logan, B., and Olsen, M. A. Partial respiratory obstruction in an infant due to bronchiogenic cyst: Report of case. Mayo Clin. Proc. 30:282, Tucker, G. Congenital cyst of mediastinum producing compression of lower trachea and eosophagus. Ann. Otol. 55:693, Williams, H. Bronchiogenic cyst in infancy causing respiratory obstruction. Med. J. Aust. 2:60, Williams, M. H. Localized pulmonary hypertrophic emphysema. J. Thorac. Surg. 24:522, Wyllie, W. G., and Pilcher, R. S. Intrathoracic cyst of intestinal and bronchial structure. Arch. Dis. Child. 18:34, Zatzkin, H. R., Cole, P. M., and Bronsther, B. Congenital hypertrophic lobar emphysema. Surgery 52: 505, VOL. 4, NO. 6, DEC.,