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Paper text:
primary sclerosing cholangitis ( psc ) is a chronic cholestatic liver disease characterized by inflammation and progressive obliterative fibrosis of the intrahepatic and/or extrahepatic bile ducts .
increasing evidence suggests that immune mechanisms play a critical role in the pathogenesis of psc , and it has been hypothesized that gut - homing lymphocytes may be the common denominator underlying both ibd and psc .
a possible nonimmune mechanism involved in psc pathogenesis is the release of toxic agents either by gut bacteria or following ischemic injury .
interestingly , antibiotics have been used to treat psc in several patient series over the years , and they exhibited benefits in some patients [ 3 , 4 ] .
these observations suggest that bacterial flora and gut inflammation might be closely associated with the pathogenesis of both ibd and psc .
psc is a serious disease that not only affects quality of life but can also have a significant effect on patient survival .
the treatment for psc is primarily supportive with the aim of controlling cholestatic symptoms and preventing complications .
ursodeoxycholic acid ( udca ) may induce biochemical improvements in patients . however , long - term pediatric studies to determine its possible benefits in young patients are lacking .
, we describe a patient with psc and undetermined colitis who was successfully treated with a combination of a steroid , salazosulfapyridine , and a probiotic .
a 13-year - old boy with a 4-week history of fever , abdominal pain and associated anemia and liver dysfunction was referred to us .
his laboratory data on admission showed the following : aspartate aminotransferase 80 iu / l , alanine aminotransferase 102
iu / l , alkaline phosphatase 2,663 iu / l , -glutamyl transpeptidase 524 iu / l , immunoglobulin g 2,180 mg / dl , and erythrocyte sedimentation rate 111 mm / h ( table 1 ) .
colonoscopy revealed pancolitis including erosive lesions with rectal sparing , but without granulomatous changes . a diagnosis of undetermined colitis was made .
a liver biopsy revealed severe biliary tract outflow obstruction and chronic active inflammation involving the biliary ducts ( fig .
treatment with udca ( 600 mg / day ) and mesalazine ( 2,000 mg / day ) was started , after which his symptoms improved temporarily .
mesalazine was replaced with prednisolone ( 30 mg / day ) , salazosulfapyridine ( 3,000 mg / day ) and a probiotic ( lactobacillus casei shirota , 3 g / day ) .
two weeks later , the patient 's symptoms and laboratory results had improved ( table 1 ) .
a repeat biopsy at 30 months showed significant improvements in inflammatory cell infiltration and periductal fibrosis and a decrease in fibrotic areas from 10.5 to 3.6% in each specimen ( fig .
children with autoimmune cholangitis should be expected to respond to immunosuppressive therapy when liver histology shows interface hepatitis , immunoglobulin g levels are elevated and autoimmune markers are present .
antibiotics have been used to treat psc and exhibited benefits in some cases [ 3 , 4 ] .
these findings suggest that bacterial flora and gut inflammation may be closely associated with the pathogenesis of both ibd and psc .
probiotics are nonpathogenic viable microorganisms that have beneficial effects for host health , disease prevention and/or treatment .
first , probiotics block bacterial pathogenic effects by producing bactericidal substances and competing with pathogens and toxins for adherence to the intestinal epithelium .
second , probiotics regulate immune responses by enhancing innate immunity and modulating pathogen - induced inflammation via toll - like receptor - regulated signaling pathways .
third , probiotics regulate intestinal epithelial homeostasis by promoting intestinal epithelial cell survival , enhancing barrier function and stimulating protective responses . for our patient , the combination of immunosuppressive therapy and a probiotic provided benefits for both ibd and psc , which suggests that bacterial flora and gut inflammation are closely associated with the pathogenesis of ibd - related psc .
suppressing bowel inflammation and maintaining bacterial homeostasis in the gut is important in the treatment of psc .
the results of a randomized controlled trial showed that probiotics alone could not control symptoms or improve liver function in adult psc patients .
however , additional studies are needed to determine the effects of probiotics as an adjunctive therapy in pediatric ibd - related psc .
primary sclerosing cholangitis ( psc ) is a serious disease that not only affects quality of life but can also have a significant effect on patient survival . 
 the treatment for psc is primarily supportive with the aim of controlling cholestatic symptoms and preventing complications . 
 ursodeoxycholic acid may induce biochemical improvements in affected patients ; however , long - term pediatric studies to determine its possible benefits in young patients are lacking . 
 thus , the treatment of pediatric psc remains a significant clinical challenge . 
 we describe a patient with psc and undetermined colitis who was treated with a combination of a steroid , salazosulfapyridine , and a probiotic . 
 this treatment provided benefits both for psc and the undetermined colitis . 
 these findings suggest that bacterial flora and gut inflammation are closely associated with the pathogenesis of inflammatory bowel disease - related psc . 
 suppression of bowel inflammation and maintenance of bacterial homeostasis may be important for treating psc .