Chylous reflux into localized pulmonary lymphangiectasis

Chyloptysis with chylopericardium, a rare case and mini-review

Background

Chyloptysis is reflux of chyle into the lungs and is a rare manifestation of primary chylous disorders.

Case presentation

Over 29 months, on the basis of x-rays, a 33-year-old female was repeatedly misdiagnosed with recurrent right-sided pneumonia; her symptoms included a recurrent cough, the appearance of cheese-like sputum, and diffuse pulmonary exudates. There was a history that abundant fluid in the pericardium was confirmed with echocardiography to have been present and asymptomatic for 4 years. Lymphangiography and surgery confirmed that the terminal portion of the thoracic duct was compressed by thick fibrous tissue and the vascular sheath of the internal jugular vein. Chyloptysis caused by high peribronchial lymphatic pressure was diagnosed and surgical intervention relieved the symptoms.

Conclusion

Chyloptysis is rare and easy to misdiagnose but is a typical symptom of chylous reflux syndrome.

[Anatomy, micro-anatomy and physiology of the lymphatics of the lungs and chest wall]

The thoracic lymphatic vessels are pulsating channels which drain actively the fluid of lung parenchyma interstitium and pleural cavities. Their unidirectional valves that avoid reflux of contents, direct the current of fluid to the connection of thoracic duct to subclavian vein or to the thoracic duct itself by these pulsations. The ascending parietal and visceral currents have anastomoses between them. The parietal currents (internal thoracic anteriorly, external axillaries in lateral and paravertebral in posterior) drain the lymph of thoracic wall. Pleural cavities and the visceral currents, drain that of lungs and mediastinal organs. The thoracic duct goes upward in the posterior mediastinum and usually connects to the venous confluent of the left subclavian vein. It receives a part of thoracic lymph and also drains the lymph of trunk and inferior limbs. About a half or two thirds of thoracic duct lymph is originated from liver and intestines. The intestines have the lymph of digestion with the fatty elements, i.e., the chyle.

Chyloptysis after ligation of the thoracic duct

Chyloptysis is a very rare clinical finding. We describe a 44-year-old man who presented with cough and milky-white sputum. Fiberoptic bronchoscopy revealed white sputum, which originated from the right B(6) bronchus. The finding of elevated triglyceride levels in his sputum led to the diagnosis of chyloptysis. He had a surgical history of ligation of the thoracic duct for idiopathic chylopericarditis 7 years-previously. He also suffered from postoperative bilateral empyema. Since then, his pleural cavity has been adhered bilaterally. It is thought that his abnormal postoperative lymphatic flow caused the chyloptysis.

Chyloptysis with right middle lobe syndrome complicated postoperatively by chylothorax: an unusual cause of right middle lobe syndrome

Chyloptysis, in the context of middle lobe syndrome, and chylothorax are rare clinical entities. They are reported in the medical literature mostly as case reports, but never together in the same patient. The present report describes the case of a 34-year-old woman who presented with chyloptysis associated with recurrent right middle lobe syndrome since she was 20 years of age, and eventually underwent right middle lobectomy. A few weeks postoperatively, she developed a right-sided chylothorax, which was refractory to medical therapy, and was successfully treated with thoracic duct ligation. She has been symptom-free for two years postsurgery.

[Surgery for chylothorax]

Chyle is lymph fluid of intestinal origin containing fat digestion products. Chylothorax is produced by leaks from the thoracic duct or from one of its collaterals subsequent to valve incompetence. These leaks may be due to trauma (post-surgical chylothorax, the most frequent) or to spontaneous rupture of a lymph vessel distended by chyle reflux, the thoracic duct itself being pathological. When the thoracic duct is interrupted (obstruction, agenesis), chylothorax may occur from leakage due to reflux within substitution collateral pathways diverting the flow of chyle into the venoux confluents of the neck. Medical treatment is always attempted first: evacuation of chylothorax by drainage and fat-free diet or parenteral nutrition. Recently, treatment with octreotide has been found to be beneficial. Surgery consists in thoracic duct ligation or suture of leaking collaterals. In difficult cases, when the chyle leakage cannot be identified, pleurodesis is the only option.

Chyloptysis in Adults

Chyloptysis is a rare finding, and the accompanying respiratory symptoms are usually nonspecific. The recognition of the chylous nature of the sputum is requisite for proper diagnosis, especially if chyloptysis is not accompanied by chylous pleural effusion. The key to the differential diagnosis of chyloptysis is to consider illnesses that can induce reflux of chyle into the bronchial tree. There are two mechanisms postulated: the first requires the presence of an abnormal communication between the bronchial tree and the lymphatic channels, and the second requires a bronchopleural fistula in the context of a chylous pleural effusion. Chyloptysis in adults should prompt assessment for evidence of lymphatic obstruction from trauma, radiation, and malignancy, and to exclude diseases with known association with chyloptysis, ie, lymphangioleiomyomatosis, yellow nail syndrome, or thoracic lymphangiectasis. A lymphangiogram is recommended to define the abnormality. In the case of lymphangiectasis, patients respond to either dietary modification and/or ligation of the thoracic duct.