Chylous ascites and chylothorax due to the existence of transdiaphragmatic shunting in an adult with nephrotic syndrome.

Chylous ascites is a well-known complication of severe nephrotic syndrome. However, the coexistence of chylous ascites and chylothorax is rarely reported in adult nephrotic syndrome [1]. A 66-year-old man was diagnosed with nephrotic syndrome 10 months before, presenting with progressive anasarca, dyspnea, abdominal fullness, persistent heavy proteinuria, and a 10.5 kg body weight gain. The pathology of his nephrotic syndrome revealed membranoproliferative glomerulonephritis. For symptomatic relief, right-side thoracentesis and paracentesis were performed and showed chylous ascites (Figure 1) and chylous effusion with triglyceride levels of 394 and 97mg/dl, respectively, which were negative for cytology and culture. To determine whether communication existed between the peritoneal and pleural cavities, 6mCi 99mTc-macroaggregated albumin (MAA) was injected into the peritoneal cavity. Radioactivity was visualized in the right thoracic cavity 5min later (data not shown) and increased in the following hour (Figure 2), a finding consistent with shunting existing between the abdomen and right thorax. The pathogenesis of chylous ascites in nephrotic syndrome is unknown, but hypoalbuminaemia-induced bowel oedema may be a predisposing factor. Chylothorax is not a usual result of nephrotic syndrome; however, if chylothorax was identified from an abdominal source, surgical exploration of the chest for diagnosis could be avoided. This patient demonstrated by means of a nuclear scan that the chylothorax was secondary to the transdiaphragmatic movement of chylous ascites and confirmed the existence of shunting between the peritoneal and thoracic cavities; however, this mechanism is uncertain, and it Correspondence and offprint requests to: Shang-Jyh Hwang, Division of Nephrology, Department of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan. Email: [email protected] Fig. 2. Supine view of a nuclear scan of the upper abdomen and chest 2 h after MAA was injected into the peritoneal cavity. Radioactivity is seen bilaterally in the peritoneal space, but in the thorax it is seen only in the right pleural cavity, indicative of the existence of shunting between the abdomen and right thorax. Fig. 1. Milky colour fluid aspirated from chylous ascites.