Diagnosis of congenital broncho-esophageal fistula in a 62-year-old male.

Congenital broncho-esophageal fistula (BEF) may go unrecognized in infancy and childhood and present later in life, due to non specific signs and symptoms. We report an adult case of congenital BEF which was diagnosed after massive aspiration precipitated by raised intra abdominal pressure due to severe acute pancreatitis.

INTRODUCTION

Undiagnosed congenital BEF may not have any complication till adulthood despite aspiration, if tracheo-bronchial clearance is normal and defense mechanisms are intact, or may having non-specific signs and symptoms like chronic cough with sputum production, bronchospasm, cough following intake of liquid food, recurrent episode of pneumonia, pulmonary abscess, chest pain, hemoptysis and low grade fever.[12] These symptoms can be present for 6 months to 50 years before being diagnosed to having fistula.[3]

CASE REPORT

A 62-year-old male was referred to the critical care medicine department from a private hospital with diagnosis of sever acute pancreatitis (day 8) and respiratory distress for 2 days. On examination his heart rate was 122/min, blood pressure was 114/66 mm of Hg, respiratory rate was 32/min with predominately thoracic respiration, abdomen was distended and tense, and bowel sounds were absent. His investigations revealed Hb 10.2 gm/dl, total leukocyte count 17,900 cell/cmm, serum creatinine 1.9 mg/dl and serum amylase of 2897 U/l. CECT abdomen was suggestive of bulky edematous pancreas with peri-pancreatic inflammation, mild lesser sac collection and multiple dilated bowel loops. His only significant past history was of chronic cough since childhood.

Due to worsening of respiratory distress, endotracheal intubation was done and he was kept on mechanical ventilation along with invasive hemodynamic monitoring. His intra abdominal pressure (IAP) was high (24 mm of Hg), so nasogastric tube was kept on free drainage. Subsequently on day three, once decrease in IAP (17 mm of Hg), nasogastric feeding was started. Within a few minutes of feeding, patient developed severe cough with feed visible in the endotracheal tube. Suspecting that patient might have been aspirated through the peritubal leak due to raised IAP, endotracheal tube was upsized to size 9.0 mm with cuff, thorough tracheal toileting was done and nasogastric tube was kept on free drainage. This time it was noticed that there was recurrent distention of nasogastric drainage bag with air. In the presence of gastric content in the respiratory tract and recurrent filling of nasogastric bag with air, patient was suspected to have communication between respiratory tract and esophagus. Bed side bronchoscopy was done, which showed gastric contents regurgitating into the right main bronchus (unfortunately we could not save the image). A diagnosis of right broncho-esophageal fistula (BEF) was made. Following aspiration patient developed septic shock and sever acute respiratory distress syndrome (ARDS) with requirement of high ventilator and vasopressor support. Chest X-ray revealed bilateral lungs infiltrate with predominant involvement of right lungs [Figures 1 and 2]. Unfortunately, in view of rapid worsening of ARDS and septic shock patient could not be taken for broncho-esophageal repair and succumbed to death in next 48 hours.

Figure 1

Chest X-ray before aspiration (on mechanical ventilation)

Figure 2

Chest X-ray after massive aspiration (on mechanical ventilation)

DISCUSSION

Various explanations with multiple mechanisms are available in literature for late manifestation of this congenital anomaly. They include oblique course of the fistula, the presence of a membrane blocking the lumen of the fistula, the presence of a valve mechanism and spasm of the fistulous tract.[4] There are four type of BEF as classified by Braimbridge and Keith.[5] Type II is the most common (almost 90%), having a short tract running directly from the esophagus to the bronchus.

In PubMed search for congenital broncho-esophageal / esophago-bronchial fistula in adult, most of the case reports are in Japanese literature, while there are about 20 cases reported in the English literature. In all likelihood, our patient had congenital BEF, with relevant past history, but he never required hospitalization for any respiratory complaint. After having severe acute pancreatitis, there was massive aspiration due to raised IAP that leads to broncho-esophageal communication to open up and when nasogastric feed was started there was massive aspiration through the BEF. Following aspiration on mechanical ventilation, increase in the mean airway pressure further worsened the BEF causing air to leak from tracheal to esophageal lumen as it was evident from repeated filling of the nasogastric drainage bag with air.

Conventional barium esophagography is the most sensitive means for the diagnosis of BEF. Other methods include bronchoscopy, esophagoscopy, and dye test.[1] Appropriate management of BEF is surgical closure[3] but our patient could not be operated upon because of severe hemodynamic instability and high ventilator support.

So, clinician should be aware of possibility of BEF in patients with significant past history of recurrent cough since childhood. Immediate diagnostics should be carried for early diagnosis, management, and prevention of life threatening complications.