Abnormal connections ( fistulas ) can develop between the esophagus and the trachea ( windpipe ) , also increasing the risk of pneumonia , which is usually heralded by cough , fever , or aspiration .
Abnormal connections ( fistulas ) occasionally develop between the esophagus and the trachea ( windpipe ) . 
 Fistulas often lead to pneumonia , which is usually heralded by cough , fever , or aspiration .