Intestinal Lymphangiectasia

Intestinal lymphangiectasia is dilatation of intestinal lymphatics leading to leakage of lymph into the lumen, causing protein losing enteropathy, fat malabsorption and lymphopenia.

• Primary (Waldmann disease): congenital lymphatic malformation, onset in infants and young children (before age 3 in most), mutations in VEGFR3, CCBE1, FOXC2, PROX1; may be sporadic.
• Secondary: constrictive pericarditis, right heart failure, Fontan circulation, mesenteric lymphatic obstruction (lymphoma, retroperitoneal fibrosis, tuberculosis), sarcoidosis, Crohn disease, Whipple disease, radiation, systemic lupus, Noonan syndrome, Turner syndrome.
• Consequence: loss of albumin, immunoglobulins, lymphocytes (T cell), and fat soluble vitamins.
• Complications: growth failure, oedema, chylous ascites, chylothorax, recurrent infections, hypocalcaemia, thromboembolism, intestinal lymphoma (rare).

• Bilateral lower limb oedema (often asymmetric, with lymphoedema), ascites, pleural and pericardial effusions, diarrhoea or steatorrhoea, abdominal pain, nausea, vomiting, growth retardation.
• Lymphopenia, hypoalbuminaemia, hypogammaglobulinaemia, recurrent infection.
• Tetany from hypocalcaemia and hypomagnesaemia.
• Associated lymphatic malformations in primary disease (lymphoedema, genital oedema).

• Laboratory: low albumin, low IgG, IgA, IgM, lymphopenia (under 1500 cells/µL), low cholesterol, hypocalcaemia, raised faecal alpha 1 antitrypsin clearance.
• Upper endoscopy: white, dilated lymphatic villi ("snowflake" or "snowstorm" appearance) and white spots, with biopsy showing dilated lacteals in lamina propria and submucosa (patchy distribution; take multiple biopsies).
• Capsule endoscopy or double balloon enteroscopy to localise lesions.
• Imaging: CT/MR enterography (bowel wall thickening, mesenteric oedema), MR lymphangiography, lymphoscintigraphy with 99mTc, abdominal ultrasound for ascites.
• Exclude secondary causes: echocardiography, CT abdomen for obstruction, tuberculosis testing, genetic testing.
• Chylous ascites: ascitic triglycerides over 200 mg/dL.

• Dietary therapy is the cornerstone: low long chain fat (under 30 to 40 g or under 10 to 15% of calories), high protein diet, supplement medium chain triglycerides (MCT oil 1 to 2 mL/kg, up to 30 to 60 mL/day), which are absorbed via the portal vein.
• Supplement fat soluble vitamins (A, D 2000 to 4000 IU, E, K), calcium (1000 to 1200 mg), magnesium, iron.
• Albumin infusions and diuretics (furosemide, spironolactone) for oedema and effusions.
• Octreotide 50 to 100 micrograms SC two to three times daily (or long acting 20 mg every 4 weeks) reduces lymph flow in refractory cases.
• Sirolimus 1 to 2 mg daily (trough 5 to 15 ng/mL) in refractory disease.
• Tranexamic acid 500 mg to 1 g three times daily, antiplasmin, sildenafil, and corticosteroids (budesonide) in selected cases.
• IVIG 0.4 g/kg for recurrent infections with hypogammaglobulinaemia.
• Total parenteral nutrition for severe disease; surgical resection for localised segmental disease or lymphatic obstruction; lymphovenous anastomosis; thoracic duct embolisation.
• Treat the secondary cause (pericardiectomy, heart failure therapy, chemotherapy).
• Lifelong dietary management for primary disease. Monitor for lymphoma and nutritional deficiencies.