The treatment modalities for gastric bezoars include endoscopic therapy with fragmentation, medical treatment by enzymatic dissolution and surgery[13
]. Various endoscopic methods and instruments for breaking up bezoars have been reported, including lithotripsy with basket[14
], endoscopic suction removal with large-channel endoscopy[15
], polypectomy snare[16
] and biopsy forceps. However, these procedures are time-consuming. Furthermore, procedure-related complications may develop, such as bleeding, overtube-associated complications and intestinal obstruction caused by the fragmented, residual bezoars. In addition, chemical dissolution usually requires a long period of time and complications may develop, such as electrolyte imbalance, gastric ulcer and bleeding. The reported efficacy of chemical dissolution is variable[3,17
Recently, Ladas et al[6
] reported a five cases of gastric phytobezoars successfully dissolved by lavage with three liters of cola. Since then, there were six reports written in English and describing the treatment of gastric bezoars with cola. However, reports on cola dissolution have been limited to individual case reports. Methods and results are summarized in Table .
Summary of cases for gastric phytobezoar treated with cola
In this series, we report the clinical results of 17 gastric phytobezoars treated with cola. To our knowledge, this is largest study ever on this topic. The therapeutic efficacy of a lavage with three liters of cola (or of drinking the same amount), to achieve the complete dissolution of bezoars, was only 23.5%. Compared with previous reports, our success rate is very low. The reason for this low therapeutic efficacy of cola may be due to the fact that most cases of our series were diospyrobezoars (13 out of 17 cases, 76.4%), and in fact we failed to observe the complete dissolution of diospyrobezoars using cola alone.
Diospyrobezoars following ingestion of persimmon are formed by the agglutination of the tannins in the skin of the fruit. Because of their hard consistency, endoscopic therapy with fragmentation or enzymatic dissolution is challenging and sometimes mechanical fragmentation cannot be accomplished. In a previous report, the efficacy of the combination of endoscopic fragmentation and pharmacotherapy was 80%[18
]. There are four reports of cases in whom the complete dissolution of diospyrobezoars was carried out with cola (Table ). The direct injection of small amounts of cola directly into the phytobezoars is also rapidly effective and safe[6,7,9
]. However, in our experience, this technique was not effective for complete dissolving huge disopyrobezoar (case 17). So, in case of diospyrobezoars, complete dissolution might not be achieved with cola use alone.
Another reason for the low therapeutic efficacy may be the relatively short duration of cola administration. There were two successful dissolution cases with daily cola drinking for longer durations (7 d[10
] and 3 mo[18
]). A prolonged administration may have changed our clinical results, but it may also have induced metabolic disturbances due to the cola’s high caloric content. Also, a longer administration time may prolong the nil per os
time and the length of hospital stay. So, we used the short duration of cola and combined it with the endoscopic fragmentation.
Cola alone could not dissolve completely all gastric phytobezoars. However, in our series, softened-consistency or decreased size was observed in all residual bezoars. So, endoscopic fragmentation and retrieval of the bezoars could be easily performed. Except for four cases, all the procedures were completed in only one session, with relative short procedure time. As the bezoars’ consistency was softened, disruption of accessories was prevented. So, these techniques are cost-effective when considering the length of the hospital stay, the number of endoscopic sessions and the used accessories. Also, using additional cola after endoscopic disruption may be helpful preventing small bowel obstruction due to daughter fragments.
Cola’s mechanism of dissolution of bezoars is not well understood. The suggested mechanisms are: (1) the mucolytic effect of NaHCO3
, (2) the digestion of the bezoar by CO2
bubbles and (3) the cola’s acidity, which is similar to that of gastric acid[6
In conclusion, the complete dissolution rate using three liters of cola was 23.5%, but no case of diospyrobezoars was completely dissolved. However, pretreatment with cola may be helpful and facilitate endoscopic fragmentation of gastric phytobezoars. A combination therapy of gastric phytobezoars with cola and endoscopic fragmentation is cost-effective and decreases the number of endoscopic sessions and accessories that are used as well as the hospital stay.