To the best of our knowledge, there have been no previously published reports in the medical literature of phytobezoars in patients with Noonan syndrome. This case represents what may be an interesting association between bezoars and gastrointestinal dysmotility related to Noonan syndrome. A study of 25 children with Noonan syndrome ranging in age from 2 months to 12 years revealed that 16 had gastrointestinal symptoms such as reflux and failure to thrive. However, difficulties with feeding often went unrecognized, and the etiology of the problem was uncertain. In this same group of patients, 7 of 25 had foregut dysmotility and gastroesophageal reflux documented by electrogastrography and antroduodenal manometry. Four of the 7 children with foregut dysmotility had abnormal gastric and small bowel myoelectrical activity that was characterized as disorganized and weak. The study authors speculated that the dysmotility and feeding difficulties were due to a delay in the development of the enteric nervous system in children with Noonan syndrome. Although many of these children improved with age, persistent dysmotility could put them at risk for the development of bezoars, such as the one seen in our patient.
The main risk factors for bezoars include gastric surgery and gastrointestinal dysmotility. Delayed gastric emptying and abnormal gastric motility patterns were prominent in one series of patients with bezoars, suggesting that these events were the underlying factors in their development. However, another series of patients with bezoars who had undergone vagotomy or pyloroplasty did not demonstrate uniformly delayed gastric emptying as assessed by technetium-99m- labeled studies. A study involving 117 patients with gastrointestinal bezoars revealed that 87% occurred in the small bowel and 30% in the stomach. Furthermore, 70% of patients had previous surgery for peptic ulcer disease, and 80% of these patients had a bilateral truncal vagotomy with pyloroplasty. Of the 87 patients presenting with intestinal bezoars, excessive intake of vegetable fiber occurred in 40%, and 24% had alterations of mastication and dentition. A review of several case series noted that bezoars were prevalent among patients with mental retardation; one study estimated that up to 10% of emergency laparotomies in mentally retarded patients may be performed because of bezoars. Another recognized risk factor for bezoars is diabetic gastroparesis.
Patients with bezoars often present with signs and symptoms of bowel obstruction, such as colicky abdominal pain, vomiting, and constipation or obstipation. Plain abdominal films can reveal dilated small bowel loops, and barium enema studies can show an intraluminal filling defect of variable size that will not appear fixed to bowel wall. Abdominal CT scan is the best diagnostic modality for detecting bezoars. The pathognomonic appearance of bezoars is that of a well-defined ovoid intraluminal mass with mottled gas pattern at the site of obstruction. Radiographic evidence of a small bowel obstruction with dilated fluid and air-filled loops proximal to the site of obstruction and distal collapsed small bowel may also be present. Definitive treatment consists of exploratory laparotomy with milking of contents to the cecum, or enterotomy. Medical treatment is usually inadequate.
There are scant recent data on the prevalence of bezoars causing mechanical small bowel obstruction, although one series from Hong Kong reported that over a 10-year period, 19 of 1020 (2%) small bowel obstructions at their hospital were related to bezoars. However, a review from the Mayo Clinic reported that only 3 of 314 (0.9%) small bowel obstructions were due to bezoars. Thus, geographical variation may exist, although the true incidence is still unknown.
Cite this: Small Bowel Bezoar in a Patient With Noonan Syndrome: Report of a Case - Medscape - Feb 21, 2007.