Incidence and Sexual Difference

Abstract

The incidence of Hirschsprung’s disease, a congenital disease, has been investigated in many countries/states and areas using different methodologies. There is some difference in reported incidences from 1 in 3030 to 7163 live births, although mostly they range from 1 in 4000 to 5000. Even the earliest report about patients with the disease demonstrated the male predominance. Male to female ratios reported vary, but they are mostly estimated between 2 and 4. Hirschsprung’s disease can be best termed as congenital intestinal aganglionosis, and it has been known that the length of the affected intestine varies in each patient. Frequencies of each type of the disease have been described in most papers and patients with short-segment aganglionosis, which is defined as one limited to up to the sigmoid colon, and are most common although their frequencies somewhat vary from 57.7% to 87.1%. Patients with long-segment type are less frequent, and the reported frequencies range from 8.2% to 26.0%. Patients with the category of total colon aganglionosis or aganglionosis beyond the terminal ileum are least frequent, and their frequencies reported are less than 10%. It has been consistently reported in a large series of patients that male preponderance of the disease tends to decrease with increasing length of the aganglionic segment. Male to female ratios of patients with short segment have been reported to be from 3.4 to 5.4 while those of patients with longer than total colon affected to be around 2.0. Even the earliest report demonstrated familial incidence and risk of a sibling to have Hirschsprung’s disease. The highest reported is 8.2% and the lowest is 2.9%. Familial transmission of the disease is much higher than the incidence of general population. Risks of having a sibling with the disease are reported ranging from 1.8% to 5.9%. As for type and familial incidence, most of the non-familial patients have rectosigmoid type, and aganglionosis extended beyond the sigmoid colon tends to be more in familial patients especially total colon aganglionosis. There is an increased recurrence risk of siblings in cases with aganglionosis extending beyond the sigmoid colon. Trisomy 21, known as Down syndrome, is the most frequent chromosomal abnormality associated with Hirschsprung’s disease. According to the meta-analysis, incidence of Down syndrome in Hirschsprung’s disease is 7.75% although the incidences reported varied widely ranging from 0.64% to 16.25%. Chronologically, incidences of the disease with Down syndrome shown increased over 30 years in Japan but that in Taiwan decreased, which may reflect social circumstances.