A 21-year-old man collapsed with anaemia (haemoglobin < 6 g/dl). He underwent immediate oesophagogastroduodenoscopy and colonoscopy which were both normal. The bleeding stopped spontaneously and, following a blood transfusion, he made a rapid recovery. His repeat blood tests showed a haemoglobin of 11.6 g/dl, mean corpuscular volume (MCV) 74 fl, platelet count 398 x 10 9 /l, ferritin 37 ng/ml and normal clotting. A barium study demonstrated a large saccular viscus in the pelvis containing food debris but it was not possible to determine whether these areas were diverticula or saccular parts of the bowel. A computed tomography (CT) scan of the abdomen revealed a large gas and debris-filled structure in the pelvis. Again, it was not possible to determine from which loop of bowel it arose but there was the suggestion of a vitelline artery supplying it. An isotope Meckel's scan using 99m-technetium pertechnatate was performed and this showed normal uptake by the gastric mucosa and normal passage of tracer distally from the stomach. However, there was no uptake seen in right iliac fossa to suggest a Meckel's diverticulum. The area that corresponded to the abnormal viscus was represented by a photopaenic area with no isotope activity within it.Soon after, he was admitted to hospital as an emergency with massive rectal haemorrhage. He underwent laparotomy when a giant Meckel's diverticulum was found. The middle of the diverticulum measured 8 cm in diameter and, on slicing, revealed the presence of a large blood clotThe trouble with investigating anaemia in young adults: bleeding from a giant Meckel's diverticulum without ectopic gastric mucosa S TANG, A ZAIDI
Department of Surgery, St Helier Hospital, Carshalton, Surrey, UKABSTRACT Giant Meckel's diverticulum is rare and usually presents in childhood with haemorrhage or bowel obstruction. Bleeding results from the presence of ectopic gastric mucosa causing peptic ulceration of adjacent mucosa. We discuss the case of a 21-year-old man with a giant Meckel's diverticulum who presented with rectal bleeding. A Meckel's scan was negative and histology following surgical excision ruled out the presence of ectopic gastric mucosa. There was however evidence of chronic inflammation and small bowel mucosal ulceration. We hypothesize that this arose from ischaemia and pressure necrosis because of the large size of the diverticulum and chronic distension by food debris. This case highlights the difficulties in investigating anaemia in young adults despite modern imaging techniques.