Hirschsprung's disease: a regional experience

Validation of algorithms to determine incidence of Hirschsprung disease in Ontario, Canada: a population-based study using health administrative data

Objective

Incidence rates of Hirschsprung disease (HD) vary by geographical region, yet no recent population-based estimate exists for Canada. The objective of our study was to validate and use health administrative data from Ontario, Canada to describe trends in incidence of HD between 1991 and 2013.

Study design

To identify children with HD we tested algorithms consisting of a combination of diagnostic, procedural, and intervention codes against the reference standard of abstracted clinical charts from a tertiary pediatric hospital. The algorithm with the highest positive predictive value (PPV) that could maintain high sensitivity was applied to health administrative data from April 31, 1991 to March 31, 2014 (fiscal years 1991–2013) to determine annual incidence. Temporal trends were evaluated using Poisson regression, controlling for sex as a covariate.

Results

The selected algorithm was highly sensitive (93.5%) and specific (>99.9%) with excellent predictive abilities (PPV 89.6% and negative predictive value >99.9%). Using the algorithm, a total of 679 patients diagnosed with HD were identified in Ontario between 1991 and 2013. The overall incidence during this time was 2.05 per 10,000 live births (or 1 in 4,868 live births). The incidence did not change significantly over time (odds ratio 0.998, 95% confidence interval 0.983–1.013, p = 0.80).

Conclusion

Ontario health administrative data can be used to accurately identify cases of HD and describe trends in incidence. There has not been a significant change in HD incidence over time in Ontario between 1991 and 2013.

Familial Hirschsprung's disease: a systematic review

INTRODUCTION

Hirschsprung's disease (HSCR) is a multi-genetic disorder with complex inheritance patterns. Population risk is 1 in 5000 but is reported to be increased in families of patients with HSCR. Appropriate counseling of affected families could be assisted by data from a large volume of patients. It was the aim of this study to systematically analyse the patterns of familial HSCR in the published literature.

METHODS

Pubmed (®) database was searched using the terms "Hirschsprung's disease" and "familial" for studies published between 1980 and 2015 on cohorts of index patients with HSCR reporting on familial recurrence. Studies giving rates of familial HSCR together with the total number of HSCR cases at that centre were included.

RESULTS

In 4331 index cases of HSCR, an overall rate of 7.6% familial recurrence was found. In total colonic aganglionosis, 20% of cases were familial. Recurrence of HSCR within families predominantly occurred in siblings (62%) and was reported between parent and offspring in 22% and in other relatives in 16%. Multiple generations were affected in 15% of families.

CONCLUSION

Familial recurrence of HSCR occurs frequently and should be discussed with families of diagnosed patients. Genetic counseling should be offered in these families and in particular for those patients with long segment and total colonic aganglionosis.