Chylous effusion

This code describes the accumulation of chyle, a milky lymphatic fluid rich in triglycerides, within a body cavity, most commonly the pleural space (chylothorax) or peritoneal cavity (chylous ascites). This effusion results from the disruption or obstruction of lymphatic vessels, leading to leakage of chyle.

Use this code when documentation explicitly states a diagnosis of chylous effusion, chylothorax, or chylous ascites. This typically occurs following trauma, surgery (especially thoracic or abdominal), malignancy, or congenital lymphatic abnormalities. Confirmation often involves fluid analysis demonstrating high triglyceride levels.

• Always specify the anatomical site of the chylous effusion if documented (e.g., pleural, peritoneal) using additional codes if available and appropriate.
• Code the underlying cause of the chylous effusion (e.g., malignancy, surgical complication, trauma) as a primary or secondary diagnosis, depending on the circumstances and official coding guidelines.
• Distinguish from other types of effusions (e.g., serous, hemorrhagic, purulent) which have different ICD-10-CM codes.