Pleural empyema secondary to nephropleural fistula in complicated pyonephrosis

Abstract

Pleural empyema of extra pulmonary origin is uncommon and empyema secondary to a fistula between the urinary tract and thorax is extremely rare. We report a case of nephropleural fistula causing massive pleural empyema in a 64-year-old woman with a long history of urological problems, including nephrolitiasis and urinary tract infection. She was admitted with sepsis, fever, chills, tachypnea, productive cough and pyuria. At clinical examination, breath sounds were reduced over the left hemithorax. CT revealed a fistulous connection from the upper left calyceal group and the pleural space. Drainage of thoracic and perinephric collection was carried out, but nephrectomy and pleural decortication were required due to haemopurulent urine and decreased hemoglobin levels during the hospitalization. This case demonstrates the unusual and prolonged evolution of an obstructive hydroureteronephrosis complicated by pyonephrosis, culminating in retroperitoneal abscess that fistulized into the pleural space, leading to empyema.

Keywords: Abscess; Computed Tomography; Nephropleural fistula; Pleural empyema; Pyonephrosis; Thoracic empyema.

Fig. 1

Axia CT image after intravenous contrast. (A) Pleural effusion on the right side. On the left hemithorax, a fluid density collection is detected within the pleural space with small air bubbles inside. The fluid collection forms an obtuse angle with the adjacent lung (*). The pleura is thickened, smooth and enhancing. At the margins of empyema, the pleura is dived into the parietal and the visceral layer (split pleural sign). (B) Dilated calicopelvic system of the left kidney with parietal thickening and inhomogeneous urine density. High density material is appreciable in the upper calyceal group. (C) On the upper pole of the left kidney adjacent to the dilated and inhomogeneous calicopelvic system, a semilunar fluid collection is appreciated adherent to Gerota's fascia. (D) Dilated left calicopelvic system with inhomogeneous high density content. Gerota's fascia is thickened (white arrow); perirenal fat is inhomogeneous. Lumboaortic nodes are detected (*).

Fig. 2

(A,B) MPR CT images after intravenous contrast. (A) Sagittal MPR image. The left kidney appeared enlarged with high grade of calicopelvic system dilatation, with parietal thickening and inhomogeneous high density urine. An abscess is appreciated posteriorly on the upper pole of the left kidney. The abscess continues with a fistulous connection that goes through the diaphragm into the pleural empyema. (B) Parasagittal MPR image. The fistulous connection between the perineal abscess and pleural empyema is clearly appreciable.