Intestinal lymphangiectasia is an uncommon condition that can present diagnostic difficulties. It may be primary or secondary. Treatment of the condition involves management of the effects of lymphangiectasia and also management of the underlying cause (in cases of secondary lymphangiectasia). Patients are usually unwell, requiring multiple investigations, often developing complications and needing considerable in-patient hospital stays. Management is frequently by a multidisciplinary team of health professionals. The following case illustrates all of the above, together with learning points and a general discussion of lymphangiectasia diagnosis and management including the underlying cause in this case.

John, a 9-year-old boy, saw his GP several times with a three-month history of cramping lower abdominal pain, diarrhoea, tiredness, difficulty sleeping and weight loss. He had been passing loose stools 6–8 times a day but without blood or mucus. His weight was 27 kg and height 132 cm, both close to the 25th centile. He looked tired and miserable but general examination was otherwise normal.

His GP considered gastrointestinal pathology and requested a full blood count, urea and electrolytes, liver and thyroid function tests, plasma viscosity, and endomysial antibodies, all of which were normal. Nevertheless, in view of the recurrent visits to the surgery with persistent symptoms, a referral was made to a consultant paediatrician. However, in the meantime, a concerned school medical officer arranged an urgent appointment with the paediatric gastroenterologist.

Five months after the onset of the illness, diarrhoea and malaise continued to be prominent symptoms, to the extent that John had now stopped attending school. There was no family history of bowel disease. A grandfather had recently died from pancreatic carcinoma. On examination John was strikingly thin and weak, with proximal muscle wasting. His weight was 22.8 kg. There were no other abnormal findings on clinical examination and in particular no lymphadenopathy …