Case Presentation: A 73-year-old male presented to the Emergency Department for a 2-month history of progressive dyspnea on exertion, orthopnea, and bilateral lower extremity edema on a background of long-standing COPD with active tobacco use. Exam was relevant for sarcopenia, mild tachypnea, decreased breath sounds in the bases, no wheezing or JVD, 2-3 + bilateral pitting edema, and his SpO2 was 86% on room air. Labs showed: albumin 2.7 g/dL and NT-ProBNP 300 ng/dL (normal range: < 540 ng/dL). His creatinine and urinalysis were normal. CXR noted small to moderate bilateral effusions. The patient was given intravenous furosemide for presumed new CHF with exacerbation and was admitted. Two months prior he had been a highly active individual and spent much of his time outside, but he had since had progressive weight loss, drenching night sweats, and anorexia. Point-of care ultrasound (POCUS) was performed at the bedside. There was no pericardial effusion and normal ventricles, with an IVC diameter of 1.2 cm and 100% collapsibility. He had an A-line pattern in the lung apices and bilateral large and simple appearing pleural effusions. Bilateral sequential thoracentesis was performed, after which he noted immediate relief in respiratory symptoms. Pleural fluid analysis revealed a chylous left pleural effusion (pleural fluid triglycerides 222 mg/dL; > 110 mg/dL is consistent with a chylous effusion) and an exudative right pleural effusion. CT chest, abdomen, and pelvis revealed diffuse centrally necrotic lymphadenopathy and a mass like soft tissue in the retroperitoneum encasing the abdominal aorta and right renal artery. The IVC appeared normal throughout. Biopsy of a retroperitoneal lymph node was positive for metastatic carcinoma consistent with renal origin, and the patient was referred to Medical Oncology.
Discussion: This case describes an interesting presentation of metastatic renal carcinoma with associated bilateral pleural effusions and hypoalbuminemia from cachexia masquerading as a new diagnosis of congestive heart failure with exacerbation. Findings on POCUS were incompatible with CHF and drastically changed management, leading to identification of a chylous pleural effusion in a patient with a subsequent new diagnosis of renal carcinoma.The diagnostic accuracy of POCUS for pleural effusions is superior to chest x-ray and similar to that of chest CT. As in this case, simple appearing pleural effusions on POCUS can still be exudative and generally require sampling to confirm.This case was also interesting as the patient had a non-traumatic chylous effusion, a rare condition. Common causes include lymphoma (much more than carcinoma), lymphatic anomalies, and cirrhosis (chylous ascites). In this patient, it was determined that the chylous effusion was due to likely lymphatic obstruction from his malignancy. We could find only one prior case of a chylous pleural effusion from renal carcinoma.
Conclusions: This case describes an interesting presentation of metastatic renal carcinoma with bilateral pleural effusions (left chylous effusion), and hypoalbuminemia from cachexia masquerading as a new diagnosis of congestive heart failure with exacerbation. With POCUS examination, he was found to be hypovolemic, without evidence of new CHF – leading to a different pathway of investigation and major diagnostic revision.