[Severe chronic constipation: limitations of medical therapy and indications for surgical intervention (diagnostic and therapeutic). I].

The great majority of children referred to Pediatric Gastroenterologic Units for chronic constipation have a functional disorder and do not require investigative techniques, since functional constipation is easily recognized an anamnestic and clinical basis. Severe chronic constipation indicates a chronic condition believed to be of functional type but unresponsive to the traditional pharmacologic treatment. However, several clinical features might suggest an organic type of constipation during the initial diagnostic approach: growth failure, distension, episodes of diarrhea intermingled with constipation, subocclusive events, dilatation of areas of the gut (megaduodenum, megajejunum) at x-ray examination of the entire gastrointestinal tract. Hirschsprung's disease is the best known organic type of constipation; however, there are other neurogenic and myogenic abnormalities of the colonic (and/or ileal) tract that mimick Hirschsprung's disease and represent development abnormalities of the enteric nervous plexus. Other organic types of constipation are due to systemic diseases, endocrine and metabolic disorders, central nervous system disorders. Organic constipation usually requires extensive investigative approach, including pathologic examination of enteric nervous plexus on full thickness biopsies.