it is well recognised that meckel s diverticulae can mimic the presentation of acute appendicitis and their presence must be sought in the case of discovery of an unexpectedly normal appendix at laparotomy .
the presence of faecaliths within meckel s diverticulae are rare and seen in approximately 1% of all meckel s diverticulae .
a 35-year old man presented with a 36-hour history of generalised abdominal pain , recently localised to the right iliac fossa .
he had a low - grade pyrexia of 37.4 c a pulse of 90 beats per minute , normal blood pressure and oxygen saturations and repeated clinical examination revealed increasing tenderness in the right iliac fossa with signs of localised peritonism .
blood tests demonstrated a mildly elevated white cell count of 12.6 x 109 cells / l with a neutrophilia of 10.3 x 109 cells / l and a crp of 43 mg / l ( normal level <
the clinical picture was highly suggestive of acute appendicitis and the patient was taken to the operating theatre .
free fluid was encountered on opening the peritoneum but the appendix was found to be grossly normal and after it s removal a search was conducted for other pathology .
the resected diverticulum was opened to reveal a large smooth faecalith 40 mm in diameter .
the histology confirmed a meckel s diverticulum with evidence of acute and chronic inflammation , haemorrhage and mucosal necrosis resulting in focal ulceration .
the picture was that of an ischaemic type inflammatory pattern resulting from pressure from the contained faecalith .
resected meckel s diverticulum and the giant faecalith it contained post - operatively , the patient admitted that , for over a year he had suffered recurrent bouts of severe colicky central abdominal pain , when running .
meckel s diverticulum was described and named by johann friedrich meckel , the younger , ( 1781 - 1833 ) , a prussian professor of anatomy(1 ) .
it is the most common congenital anomaly of the gastro - intestinal tract and represents persistence of the vitello - intestinal duct , which is normally obliterated within the first 8 weeks of gestation . during early foetal life
when present , it is situated on the ante - mesenteric border and may be connected to the umbilicus via a band .
traditional teaching is that meckel s diverticulae follow the  rule of twos : i.e. they occur in 2% of the population , are two inches long and are located within 2 feet of the ileocaecal junction .
ectopic mucosa is encountered frequently and the most common type is ectopic gastric mucosa but ectopic pancreatic tissue can also be found ( 2 ) .
carcinoid tumours are the most common malignancy encountered within a meckel s diverticulum but adenocarcinoma and sarcomas also occur .
the most common presentation in children is obstruction where the diverticulum forms the lead point of an intussusception .
it can also present with rectal bleeding ( due to ectopic gastric mucosal acid secretion causing ulceration to surrounding small bowel mucosa ) , or as diverticulitis mimicking appendicitis .
if the meckel s diverticulum is connected to the umbilicus via a band , a volvulus can occur . in adults
the most common presentation is bleeding followed by obstruction and diverticulitis but the vast majority are discovered incidentally during operations for another indication ( 3 ) .
ninety percent of meckel s diverticulae occur within 90 cm of the ileocaecal valve and the prevalence of meckel s diverticulae appears to be equal between the sexes but males seem more likely to develop symptoms with a ratio of 3:1 ( 4,5,6 ) .
a study by the mayo clinic examined all meckel s diverticulae encountered over a 50-year period ( n=1476 ) .
they found faecaliths in only 6% of symptomatic meckel s diverticulae and an even lower incidence in those that were asymptomatic .
overall they found 1% of meckel s diverticulae contained faecoliths equating to a total of 17 cases over 50 years .
acute ( 5,6 ) and chronic presentations ( 7 ) due to the presence of a faecolith within a meckel s diverticulum have been described in the literature . while the case for removal of symptomatic diverticulae is clear ( 8) , the question of whether or not to resect an incidentally discovered meckel s diverticulum remains debatable ( 9 ) with some advising against , especially in females ( 2 ) .
some advocate removal of all meckel s diverticulae due to the low risk of post - operative complications versus the lifetime risk of developing problems with the diverticulum ( 10 ) .
others suggest a selective approach with the decision to resect an asymptomatic diverticulum being positively influenced by a patient s age ( < 50 years ) , male sex , diverticulum length greater than 2 cm or the presence of abnormal tissue within the diverticulum .
palpation of meckel s diverticulae is , however , reported to be unreliable in the detection of histologically abnormal tissue .
acute presentations associated with meckel s diverticulae are a fairly rare phenomenon in the adult population and the presence of a giant faecalith within the diverticulum precipitating the presentation is extremely rare .
the surgeon finding an unexpectedly normal appendix at operation must consider meckel s diverticulum and look for it .
the decision to resect an incidental meckel s diverticulum is probably best made on a case - by - case basis , weighing up the risk of post - operative complications versus the lifetime risk associated with leaving the meckel s diverticulum in situ .
 meckel s diverticulae can present with symptoms and signs mimicking acute appendicitis . 
 we present the case of a healthy 35-year old male who was suspected of having acute appendicitis but at operation was found to have an inflamed meckel s diverticulum containing a giant faecalith , which had caused ischaemic necrosis due to a pressure effect . 
 post - operatively the patient admitted to a year of recurrent bouts of severe colicky abdominal pain , when running . 
INTRODUCTION
CASE REPORT
DISCUSSION