Aims: To investigate the incidence of melanosis of the vermiform appendix in a paediatric population, and look for correlations with season, apoptotic rate and inflammation as possible causes.
Methods and results: We examined 300 appendices removed for abdominal pain and incidentally during other procedures over the period January 1996 to March 1999. Melanosis was present in 46% of adequate specimens with an even distribution between sexes and age groups. The two older age groups had a relatively higher incidence of severe involvement compared with the younger age group, although the difference was not statistically significant. We attempted to correlate the presence of melanosis with the season of the year and the peak incidences of paediatric gastrointestinal disease but could find no relationship. No statistically significant correlation was found between apoptotic rate and the presence of melanosis.
Conclusions: The findings suggest melanosis of the appendix is relatively common. It is probably due to apoptosis associated with increased epithelial cell turnover due to many differing causes including infection, with purgative ingestion probably involved in only a minority of paediatric cases.