An assessment of the accuracy of contrast enema for the diagnosis of Hirschsprung disease at a South African tertiary hospital

Abstract

Objectives: To compare radiological findings with the histological diagnosis of Hirschsprung disease (HD) to establish the usefulness of contrast enema as an initial screening and diagnostic tool. To correlate accuracy of radiological diagnosis at Grey’s Hospital with international standards.Materials and methods: Systematic searches were conducted through the Picture Archiving and Communication System and the National Health Laboratory Service records for patients aged 0–12 years, with clinically suspected HD, for whom both contrast enemas and rectal biopsies were performed between 01 January 2011 and 31 August 2015 in a tertiary-level hospital. A total of 54 such patients were identified. Diagnostic accuracy levels were calculated by comparing radiological results with histology results, which is the gold standard.Results: Diagnostic accuracy of contrast enema was 78%, sensitivity was 94.4% and the negative predictive value was 95.7%. Specificity (68.8%) and positive predictive values (63%) were considerably lower. A lower false-negative rate of 5.6% was obtained at Grey’s Hospital as compared with the international reports of up to 30%.Conclusion: Contrast enema remains useful as an initial screening and diagnostic test for HD. Results of this South African tertiary referral hospital were consistent with the best international results for sensitivity of the contrast enema (approximately 80% – 88% in excluding the disease).