Abstract Introduction
Chylothorax is a rare and complex disorder. Causes include neoplasia, thoracic trauma, fungal infection, dirofilariasis, cardiac disease, cranial vena caval thrombosis, and congenital anomaly of the thoracic duct. Most cases are idiopathic which are difficult to resolve medically or surgically.1,2 Currently, thoracic duct ligation is the preferred technique, but invasive surgery and guarded prognosis for resolution makes this procedure less than desirable.3 Rutin, a bioflavinoid has been utilized as an alternative to traditional treatments in domestic species with reports of substantial improvement.4,5
Case Report
During routine preshipment examination of a 19-yr-old female, black and white ruffed lemur (Varecia varecia), inhalant anesthetic irregularities, decreased SpO2, and thoracic radiograph abnormalities were encountered.
Thoracocentesis, thoracic ultrasonography and echocardiography were performed to confirm unilateral (right-sided) pleural effusion. The fluid was ultimately determined to be chylous, but as no cause was identified, idiopathic chylothorax was diagnosed.
Rutin, (General Nutrition Corp., Pittsburgh, PA, 500 mg, p.o., s.i.d) was initiated and patient compliance was excellent. Physical exam, thoracic radiographs, and thoracocentesis, when appropriate, were performed twice monthly to monitor progress and resolution.
Results and Discussion
At 6 mo post-diagnosis, a negligible amount of pleural effusion remains with no associated clinical signs. Rutin administration is planned for at least 12 mo and recheck interval has been extended to 3–6 mo. The incidence of idiopathic chylothorax is unknown in non-domestic species.
Rutin is a naturally occurring compound found in buckwheat, black tea, and apple peels. Literature indicates that rutin may have antioxidant, anti-inflammatory, anticarcinogenic, antithrombotic, cytoprotective and vasoprotective activities.6
In the treatment of chylothorax, the exact mechanism of action for rutin is poorly understood. It is thought to reduce vessel leakage, increase protein removal by the lymphatic vasculature, stimulate phagocytosis by macrophages, increase the number of macrophages, inhibit lipid proteolysis, and increase lymph proteolysis and removal from tissue.7-9
Rutin is generally well tolerated. Reported adverse reactions include gastrointestinal signs, such as diarrhea and nausea. Rare reports of headache and mild tingling of the extremities are found in the human literature. From this case, rutin appears as a safe and effective alternative to more invasive treatments for chylothorax in nonhuman primates.
Literature Cited
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6. Rutin, March 14, 2004. https://www.pdr.net.
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