Encapsulated pleural effusion simulating mediastinal tumor; report of two cases.

Abstract

The purpose of this report is to describe two cases of encapsulated paramediastinal pleural effusion which strongly simulated mediastinal tumors. In so far as it has been possible to determine, similar cases have not heretofore appeared in the literature. Since failure to recognize this condition might well lead to the performance of an unnecessary thoracotomy, it would appear important to add this disorder to the many others which must be considered in the differential diagnosis of apparent mediastinal masses. Case Reports Case I: S. S., a 38-year-old white man, was admitted to the U. S. Naval Hospital, St. Albans, N. Y., on Feb. 23, 1950, with a history of frequent attacks of mild precordial pain during the two years preceding admission. These attacks were precipitated by fatigue or excitement but not by exertion. The diagnosis of arterial hypertension had been made four years previously and the patient was receiving disability compensation for that disorder. His blood pressure was said to average about 190/120. There was no history of cardiac decompensation. Frequent attacks of headache and vertigo had occurred during the three or four years preceding the onset of his present illness. Ten days before admission there had been a severe attack of precordial pain. The pain originated along the left border of the sternum in the region of the fifth anterior interspace and radiated to the left shoulder, down the left arm, to the fourth and fifth fingers of the left hand. The family physician, after making an examination and taking an electrocardiogram, told the patient that he had a “heart strain” and prescribed bed rest and mild sedation but the symptoms failed to subside. A slight nonproductive cough and a low-grade fever developed. Malaise and weakness became noteworthy and the patient sought hospitalization. The patient had undergone yearly physical examinations because of hypertension and during the course of the routine study carried out ten days before the onset of his present illness a chest film had been taken. It was reported as negative. Admission physical examination showed few remarkable findings. The blood pressure was 195/140. The heart was enlarged to the left. The aortic second sound was accentuated. There was dullness to percussion and breath sounds were absent over the left base posteriorly. No râles or friction rubs were heard. The right chest showed no abnormal findings. Both testes were atrophic. A serologic test was negative and routine laboratory findings were within normal limits except for a leukocytosis of 17,200. The differential white blood count showed no significant departure from normal. A postero-anterior chest roentgenogram (Fig. 1) showed a sharply circumscribed, smoothly marginated, rounded homogeneous area of increased density projecting to the left at the level of the pulmonary conus. Aneurysm of the left pulmonary artery was among the diagnostic possibilities prominently considered at that time.