Intestinal Obstruction Caused by Potato Bezoar in Infancy: A Report of Three Cases

We present a report of three young infants with unusual intestinal obstruction caused bypotato bezoar. They presented with vomiting, irritable crying, and abdominal distention.Barium gastrointestinal series clearly revealed intraluminal filling defect in the duodenum intwo cases and ileum in one. Those bezoars in the pylorus and duodenal bulb were all successfully retrieved endoscopically. The patient’s abdominal symptoms subsided after the bezoarswere eliminated; no subsequent gastrointestinal events occurred in the following months. Theauthors believe that the occurrence of these cases suggest that feeding mashed potato toyoung infants (≤4 months) should be prohibited because it can result in bezoar formation.Copyright©2012, Taiwan Pediatric Association. Published by Elsevier Taiwan LLC. All rightsreserved.

1. Introduction

Food-related, bezoar-associated gastrointestinal (GI)obstruction in infancy is uncommon.1The most commonbezoar reported in infancy is lactobezoar.We herein reportthree young infants with unusual intestinal obstruction caused by feeding of mashed potato. Endoscopic examinationrevealed bezoars in the stomach and duodenum. To the bestof our knowledge, there has been no report of intestinalobstruction caused by potato bezoar in infancy.

2. Case Reports

2.1. Case 1

A 3-month-old female infant suffered from decreasedappetite, abdominal distention, and vomiting for 3 days. Atadmission, she appeared dehydrated, and her vital signs showed tachycardia (156 beats/min). Hemography showedunremarkable results. Biochemistry tests showed hypokalemia (2.8 meq/L). Plain abdominal radiograph showeddilated stomach. Endoscopy was performed, revealinga bezoar impacted in the pylorus; then, the bezoar wassliced by snaring it into two pieces and removed. Aftertracing the feeding history of the patient, we found thatshe had been fed with mashed potato 1 day before onset ofsymptoms. Improvement of abdominal distention andvomiting were found on the following days. The patient hada smooth diet with liquid and rice, and she experienced anuneventful course and normal growth in the followingmonths.

2.2. Case 2

A 4-month-old male infant presented to the emergencydepartment with a 2-day history of irritable crying, vomiting, and abdominal distention. On physical examination, heappeared severely dehydrated. The vital signs showedtachycardia (155 beats/min). The abdomen was distendedwith hypoactive bowel sounds; there was neither tenderness nor a palpable mass. Blood tests revealed leukocytosis(12,700/mm³), hyponatremia (127 meq/L) and hypokalemia(2.9 meq/L). After fluid resuscitation, electrolyte replacement, and placement of a nasogastric tube were performed, the patient had persistent abdominal distention onthe following day. The patient’s mother recalled that thechild was fed with mashed potato 12 hours before the onsetof symptoms. Endoscopy was performed, revealing a bezoarimpacted in the pylorus. The bezoar was retrieved endoscopically by grasping forceps. The patient had progressiveabdominal distention, and his vomiting did not subside 1day after bezoar retrieval. Plain abdominal radiographydemonstrated small-bowel ileus. Abdominal ultrasoundrevealed diffuse dilated bowel loops and an echogenic imagewith hyperechoic arc-like density, with surface castinga posterior acoustic shadow in a dilated bowel, suggestingthe remaining bezoar (Figure 1). A round bezoar (2.5 cm indiameter) passed through the intestinal tract on the nextday, and the patient experienced an uneventful recovery.

2.3. Case 3

A 3-month-old male infant presented to the emergencydepartment with bilious vomiting, abdominal distention,and irritable crying for 2 days. At admission, he lookedacutely ill with severe dehydration, and vital signs showedtachycardia (150 beats/min). Blood tests revealed leukocytosis (17,600/mm³), hyponatremia (130 meq/L) andhypokalemia (3.0 meq/L). Plain abdominal radiographyrevealed dilated stomach and duodenal bulb, indicatingduodenal obstruction. An upper GI series demonstrated anintraluminal filling defect impacted in the second portion ofthe duodenum (Figure 2). From detailed interrogation, itwas found that the patient had been fed with mashedpotato a few hours before onset of symptoms. Emergencyendoscopy revealed dilated, hyperemic duodenum withmilk retention. After suction of the retained milk, a bezoarimpacting in the duodenum was visualized. The bezoar wasretrieved and sliced by snare forceps, and then retrieved successfully. The patient’s irritable crying, abdominaldistention and vomiting ceased from the second day ofadmission. A small bowel series was performed 2 monthslater, revealing normal caliber and smooth flow in theduodenum, jejunum and ileum.

3. Discussion

Our results agree with the claim that diagnosis of GI bezoarscan be made on the basis of history, clinical features andplain abdominal radiographs if the condition is suspected.4Hypokalemia was consistently found in our patients due topersistent vomiting and anorexia. On the basis of ourMedline and Google searches, potato peels were reportedto cause gastric phytobezoars, especially in gastrectomizedpatients,5,6whereas peeled mashed potato feeding causing

bezoar formation has not been reported previously. Potatoconsists mostly of carbohydrate, whose predominant formis starch; a small portion of such starch is resistant todigestion by enzymes in the stomach and small intestine.7Cooking method can affect the proportion of suchdigestion-resistant starch, which increases to 7% aftercooking and 13% after cooling.8Propulsion of food down theGI tract relies on the coordinated action of muscles in thebowel wall. Carbohydrate digestion is normally an efficientprocess that is completed in the distal duodenum. Infants<6 months of age normally have low levels ofa-amylaseactivity in the duodenum and therefore have potential forstarch maldigestion.9The muscular action of digestion isrelatively immature in infants; their migrating motorcomplexes may occur less often, hence the ineffectivepropulsion. We speculate that bezoars are formed by theimmature muscular action of digestion, and maldigestion ofmashed potato in early infancy.

Bezoars have been reported in the small bowel, mostcommonly in the jejunum and ileum, but rarely in theduodenum. Dysmotility of the duodenum following surgeryfor jejunal atresia may lead to bezoar formation,yet nocongenital or any predisposing factors were found in thecase with bezoar impacted in the duodenum. Radiolucentbezoars cannot be visualized on plain radiographs. Therefore, symptoms suggesting bezoar-associated obstructionwarrant investigation. Barium studies have been shown tobe effective in the diagnosis of bezoars and can be used tooutline concretion in the stomach or small bowel.10Theclassic appearance of bezoars on barium study is an intraluminal filling defect with a mottled appearance, anddilated intestinal segments can be seen proximally.10,11Sonographic features of an intraluminal mass withacoustic shadowing or strong first-interface reflection ofsound and dilated bowel loops could lead one to includebezoar-induced intestinal obstruction in the differentialdiagnosis.In comparison to sonography and barium GIseries, computed tomography shows more effective exhibition of characteristic bezoar images, and revealsconcomitant gastric and intestinal bezoars.13The diagnosisof bezoar by computed tomography is based on identifyinga low-density intraluminal mass containing air bubbles andexhibiting the characteristic mottled appearance.

Multiple bezoars occurred in one of our patients, andsimilar situations have been reported previously.4,13,15When a child has a small bowel obstruction caused bya bezoar, the stomach needs to be thoroughly evaluatedbecause the incidence of concurrent gastric bezoars isapproximately 20%.16From the experience of Case 2, wesuggest a forthcoming clinical evaluation of a possible smallbowel obstruction when there is a gastric bezoar retrievedby endoscopy. Small bezoars in the stomach may beretrieved endoscopically or eliminated by enzymatic fragmentation. Surgery is reserved for those patients who havecomplications of obstruction, perforation, or GI bleeding.

We conclude that mashed potato feeding should beprohibited in infants aged≤4 months because it can resultin bezoar formation. Abdominal symptoms usually appearwithin the first 24 hours if such a condition occurs. Flexibleendoscopy offers an effective method for removing bezoarsimpacted in the stomach and duodenum. An intraluminalmass with the surface of a highly echogenic arc-like echoand acoustic shadowing on abdominal ultrasound helps todiagnose intestinal bezoars. Cautious follow-up of abdominal symptoms is necessary if the bezoar has passed beyondthe pylorus, or if it has been retrieved endoscopically.