Introduction Technetium-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) labelled white cell scintigraphy (WCS) is frequently used in the assessment of patients suspected of having active inflammatory bowel disease (IBD). However, no previous systematic review and meta-analysis has assessed the sensitivity, specificity, and positive and negative predictive values of this investigation in comparison with colonoscopy and histology. We therefore aim to present these data here.
Methods The MEDLINE and EMBASE databases were searched to January 2014. Prospective and retrospective cross-sectional studies recruiting adults suspected of a new diagnosis or flare of IBD, and comparing Tc-99m HMPAO labelled WCS with colonoscopy and histology, were eligible. True positive, false positive, true negative and false negative findings were pooled. A random effects model was used to obtain overall data for sensitivity, specificity, and positive and negative predictive values with a 95% confidence interval (CI).
Results We identified 15 eligible studies reporting data from 635 patients (174 Crohn’s disease, 164 ulcerative colitis, 136 non-IBD). In total 1300 bowel segments were examined with 698 true positives, 41 false positives, 461 true negatives and 100 false negatives. Sensitivity was 0.90 (95% CI 0.85 to 0.95), specificity was 0.91 (95% CI 0.87 to 0.94), positive predictive value was 0.95 (95% CI 0.92 to 0.97) and negative predictive value was 0.83 (0.76 to 0.89).
Conclusion Tc-99m HMPAO labelled WCS is a sensitive and specific test for the diagnosis of active inflammatory bowel disease. Physicians may therefore find this a useful test for those in whom colonoscopy and histology are impractical or contraindicated.
Disclosure of Interest None Declared.