Intestinal lymphangiectasia

Intestinal lymphangiectasia is a disorder where the lymph vessels that comprise part of the lining of the small intestine are dilated. It is a rare disorder and affects males and females equally. Medical experts do not know the prevalence of the disease, though some believe it may be more common than is thought, since the disease can be asymptomatic. Intestinal lymphangiectasia is often diagnosed in early childhood or at birth but can be diagnosed in adults.

Definition & Facts

The dilated lymph vessels that characterize intestinal lymphangiectasia bring fats from the small intestines to the liver, but when they are dilated they can burst and spill into the large intestine. This causes a deficiency of lymph in the small intestine, which in turn causes deficiencies of proteins such as globulins and albumin.

Cholesterol levels are also abnormally low, as are levels of lymphocytes. These white blood cells are part of the body’s immune system and help defend it against infection. However, most patients with intestinal lymphangiectasia are spared opportunistic infections.

Symptoms & Complaints

• Edema or swelling of the legs. Sometimes a finger pressed into the swollen area leaves an impression. If the disease progresses, the edema affects the patient’s arms, abdomen, face, and genitals. This is because of the low levels of albumin. The membrane around the heart and the lungs can also swell. In rare, life-threatening cases, the patient’s entire body swells. 
• Mild diarrhea.
• Passage of foul-smelling, fatty stool.
• Fatigue.
• Nausea and vomiting.
• Pain or discomfort in the abdomen.
• Unintended weight loss.
• Failure to thrive in babies.
• Iron-deficiency anemia.
• Calcium deficiency and vitamin deficiency so severe that they cause convulsions in some children.
• Soft bones caused by lack of vitamin D.

In some cases, the contents of the intestine don’t move forward the way they should. Sometimes, if patients with this problem vomit, their vomit may have fecal matter. Sometimes doctors discover a mass in the abdomen, either through physical examination or imaging tests. These masses are benign and are often found in the upper part of the small intestine, or the duodenum. In rare cases, patients present with yellow nails.

There can sometimes be a back flow of chyle into the skin because of the burst lymph vessels. Chyle is milk-like fluid made up of free fatty acids and lymph. It is made in the small intestine to help digest fats and should be taken up by the lymph vessels. In intestinal lymphangiectasia, it enters the skin of the patient’s right flank and forms tiny, fluid-filled blisters. It can also flow into the lower limbs and the genitals.

A rash called necrolytic migratory erythema afflicts some patents. The rash brings blisters that burst and crust over. It is most often seen around the mouth, but it can also affect the patient’s limbs and abdomen. An uncommon symptom called recurrent hemolytic uremic syndrome can lead to kidney failure in children. 

Causes

No one knows what causes intestinal lymphangiectasia. Rarely, members of the same family come down with it but it does not seem to be passed down from parent to child. It is not caused by a pathogen or by the degradation of villi, which are the tiny, finger-like structures that help the small intestines absorb and digest nutrients. Researchers believe that something must go wrong with the genes that control the development of the lymph system. These genes include VEGFR3 gene, PROX1 gene, SOX18 gene, and FOXC2 gene.

Diagnosis & Tests

One method of diagnosis is endoscopy. This involves an endoscope which is a long, flexible tube that is passed into the patient’s mouth and down through their gastrointestinal tract. The endoscope collects tissue from the small intestine. The tissue is sent to a lab and studied by a pathologist, who is able to see the abnormally dilated lymph vessels. 

Albumin scintigraphy can reveal leakage of albumin into the gut. Ultrasound and computed tomography (CT) scans find thickened intestinal walls, edema, abnormal enlargement in the folds of the intestines and other abnormalities. Lymphoscintigraphy is used to reveal edema in the limbs caused by the build-up of lymph fluid.

Sometimes the disorder can be found before birth. Prenatal ultrasound can reveal swelling in the fetus’ lower limbs or an overall edema.

Treatment & Therapy

Intestinal lymphangiectasia is best treated with a low fat diet that is supplemented with medium-chain triglycerides (MCT), which are found in palm and coconut oil. Medium-chain triglycerides bypass the intestines and are absorbed directly into the bloodstream, and supply the body with necessary fat while sparing the lymphatic vessels.

Patients often see relief of their symptoms after they have been on this diet for a few weeks. Though the diet makes them feel better fairly quickly, they’ll need to stay on it for the rest of their lives if they do not want the symptoms of intestinal lymphangiectasia to return.

Patients who don’t respond to this low-fat diet may need tube feeding, which is delivered through the patient’s GI tract. Other treatments include tranexamic acid. This is medication that is supposed to raise the levels of T-lymphocytes and immunoglobulin. A drug called octreotide led to improvement in at least one patient, though doctors believe it works best when taken with a low-fat diet.

A few patients find relief in surgery to remove part of their small intestine, and other patients are treated with corticosteroids or receive albumin intravenously.

Prevention & Prophylaxis