Acidic and basic solutions dissolve protein plugs made of lithostathine complicating choledochal cyst/pancreaticobiliary maljunction.
BACKGROUND
Symptoms of choledochal cysts are caused by protein plugs made of lithostathine, which block the long common channel and increase pancreaticobiliary ductal pressure. Agents that dissolve protein plugs can provide relief from or prevent symptoms. In the present study, drugs reportedly effective for pancreatic and biliary stones were used in dissolution tests.


METHODS
Protein plugs were obtained from choledochal cysts during surgery in two children (5- and 6-year-old girls). Plugs approximately 2 mm in diameter were immersed in citric acid, tartaric acid, dimethadione, bromhexine, dehydrocholic acid, sodium citrate, hydrochloric acid, and sodium hydroxide solutions under observation with a digital microscope. The pH of each solution was measured using a pH meter.


RESULTS
Plugs dissolved in citric acid (5.2 mM; pH 2.64), tartaric acid (6.7 mM; pH 2.51), dimethadione (75 mM; pH 3.70), hydrochloric acid (0.5 mM; pH 3.13), and sodium hydroxide (75 mM; pH 12.75) solutions. Plugs did not dissolve in dimethadione (7.5 mM; pH 4.31), bromhexine (0.1%; pH 4.68), dehydrocholic acid (5%; pH 7.45), and sodium citrate (75 mM; pH 7.23) solutions.


CONCLUSIONS
Protein plugs in choledochal cysts are dissolved in acidic and basic solutions, which may eliminate longitudinal electrostatic interactions of the lithostathine protofibrils.
Kaneko
Kenitiro
K
Department of Pediatric Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8560, Japan. kkaneko@med.nagoya-u.ac.jp
Ono
Yasuyuki
Y
Tainaka
Takahisa
T
Sumida
Wataru
W
Ando
Hisami
H
D000143:Acids; D002648:Child; D002675:Child, Preschool; D049448:Cholangiopancreatography, Magnetic Resonance; D015529:Choledochal Cyst / Q000378:metabolism*; D003135:Common Bile Duct / Q000002:abnormalities* / Q000473:pathology; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D051847:Lithostathine / Q000032:analysis / Q000187:drug effects*; D010183:Pancreatic Ducts / Q000002:abnormalities*; D011506:Proteins / Q000737:chemistry*; D012997:Solvents / Q000494:pharmacology*; D017550:Spectroscopy, Fourier Transform Infrared
D000143:Acids; D051847:Lithostathine; D011506:Proteins; D012997:Solvents