Meckel's scan in children: a review of 183 cases referred to two paediatric surgery specialist centres over 18 years.

AIM: To review our practice of Meckel's Tc-99m pertechnetate scans over 18 years with regard to indications for the test, sensitivity and specificity in our particular referral patients' population.
MATERIALS AND METHODS: This is a retrospective review of Meckel's scans performed in two paediatric tertiary care teaching hospitals from April 1993 to March 2011 and followed up till October 2011. The scan was performed according to published international guidelines. 183 patients were included in this study. We classified the patients into two groups: group 1, which included 77 patients (42 %) presenting with painless per rectum bleeding, and group 2, which included 106 patients (58 %) presenting with other non-specific symptoms (e.g. abdominal pain, possibly associated with nausea and/or vomiting, failure to thrive). Data were analysed using Chi square test, considering P value less than 0.05 as significant. The age of the patients ranged from 4 days to 16.5 years (median 3 years).
RESULTS: 161 of the total 183 children on the study (88 %) had a negative Meckel's scan, and 22 children (12 %) had a positive scan. In the group with a positive Meckel's scan (22 children), all patients underwent surgical exploration and ectopic gastric mucosa was found in 17 cases (77 %, true positives). In the remaining 5 cases (23 %), there was no evidence of ectopic gastric mucosa (false positives). Within the group with a negative scan, 8 children (5 %) underwent surgery; only 1 child had a ectopic gastric mucosa detected following surgery (false negative). In other 52 children (32 %) of the group with a negative Meckel's scan, an endoscopy was done, which showed a normal result in 21 children and was abnormal in 31 children. Of the remaining 101 (63 %) children with a negative Meckel's scan, 74 children (46 %) improved without any further intervention. In 13 cases (8 %), other pathologies were identified. The sensitivity and specificity of the Meckel's scan for ectopic gastric mucosa were 94 and 97 %, respectively. The Meckel's scan was positive in 26 % of the patients of group 1 and in only 2 % patients of group 2. The difference between the two groups was highly significant [P < 0.0001 (Yates-corrected Chi square); odds ratio 18 (Woolf-logit method 95 % CI)].
CONCLUSION: The Meckel's scan retains a high diagnostic accuracy in children for detecting a Meckel's diverticulum with ectopic gastric mucosa within it, when performed according to the recommended guidelines. The test yields its highest positive result in children presenting with significant per rectum bleeding.