Etiology and pathology of eating rejection after prolonged prohibition of oral intake in infancy

Abstract

A number of children who had been treated in the neonatal intensive care unit cannot eat solid or viscous materials although they have no major anatomical and functional problems concerning oral movements．It has been attributed to the prolonged and complete prohibition of oral intake beyond the critical period for acquiring tolerance to tactile and pressure stimulation by food．

We investigated detailed history of oral intake，related diseases，and response to treatment，in addition to present neurological and oropharyngeal problems in nine patients with eating rejection，in order to elucidate underlying etiology for rejection．We especially focused on the influence of the critical period．All patients had experienced complete prohibition of oral intake for a long period； six had been completely prohibited oral intake since their birth，whereas the other three had taken a certain amount of milk orally before prohibited period after surgerical intervention for digestive organs．Mean corrected age for initiation of oral intake and participation in oral-stimulation program during the prohibited period of the former six patients were not significantly higher than those of 19 control children who could eat properly after a long prohibition of oral intake since birth．Disorders of digestive or respiratory organs and oropharyngeal hypersensitivity (including taste) were significantly more frequent in these patients than in controls．In the treatment procedure，desensitization was more difficult when prohibited periods were beyond the critical period．

The results suggest that prohibition of oral intake beyond the critical period is at least partially related to the rejection to eat．Accumulation of the noxious stimulation in the course of treatment for digestive or respiratory disorders and underlying hypersensitivity associated with developmental disorders might also play an important role for the pathogenesis．Treatment procedures comprising desensitization of hypersensitivity，slower induction of food and taste，counseling for family，and cooperation with day nursery were effective．