Langerhans' cell histiocytosis as a cause of periportal abnormal ...

374 M. Kim et al.: MRI of hepatic Langerhans’ cell histiocytosisTable 1. Clinical data and outcome in three childrenCase Age (mo) Sex Presenting symptoms Organs involved Outcome, treatment1 11 M Poor oral intake Skin, lymphnodes, liver2 24 M Abdominal distension,Scalp, livervomiting, and diarrhea3 18 M Limping gait Ilium, spine,liverHepatic dysfunction, aliver transplantationHepatic dysfunction, aliver transplantationStable, chemotherapya Hepatic dysfunction developed 1 1 ⁄2 years after an initial presentationTable 2. Summary of MR imaging and pathologic findings of the liverin three childrenCase MR imaging Pathology1 Smooth hepatic surface,diffuse PASI2 Nodular hepatic surface,diffuse PASI, unevenlydilated intrahepatic bileducts3 Smooth hepatic surface,mild PASI in centralportal tractshowed hepatosplenomegaly and thickly crusted patches on the scalp.Laboratory examination showed an elevated serum level of alkalinephosphatase (1075 IU/L), aspartate aminotransferase (134 IU/L), andalanine aminotransferase (121 IU/L).US showed heterogeneous hepatic parenchymal echoes and periportalhypoechogenicity. MR images of the liver showed thick, abnormalPASI, intrahepatic bile duct dilatation, and nodular appearance of theenlarged liver (Fig. 2A,B). On contrast-enhanced T1-WIs, relativelyhypointense nodular lesions were found adjacent to an abnormal periportalenhancement (Fig. 2C).In addition to the findings typical of LCH from biopsy of thescalp and liver, secondary changes of extrahepatic bile duct obstructionand cholangitis were seen. Although chemotherapy had beencontinued for 1.5 years, he developed hematemesis and melena. Hereceived a liver transplantation from a cadaveric donor. Gross andmicroscopic examination of the explanted liver showed nodularhepatic surface, severe secondary sclerosing cholangitis, and bileduct proliferations.Case 3Biliary cirrhosis, extensiveperiportal fibrosisBiliary cirrhosis, extensiveperiportal fibrosis, secondarysclerosing cholangitisBile ductular proliferation,periductal histiocytes, andinflammatory cellsPASI; periportal abnormal signal intensity on T1, T2, and contrastenhancedT1 weighted imagesA 18-month-old boy presented with a limping gait. Physical examinationshowed hepatomegaly. Laboratory examination showed an elevatedserum level of alkaline phosphatase (626 IU/L), aspartate aminotransferase(53 IU/L), and alanine aminotransferase (186 IU/L). An osteolyticlesion of the right iliac bone and flattening of the 8th and 9th thoracicvertebrae were found on plain radiographic examination.US of the liver showed slightly increased parenchymal echoes andsmall round hypoechoic nodules in the left lobe. MR images of the livershowed PASI confined to the central portal tract (Fig. 3A,B).The diagnosis of LCH was made from biopsy of the right ilium andthe liver. Liver biopsy showed bile ductular proliferation, periductalhistiocytic, and lymphocytic infiltration. Chemotherapy was initiatedwith prednisolone and vinblastine and was then continued with cyclophosphamideand VP-16. On follow-up MR images obtained 2 yearslater, PASI showed near complete resolution (Fig. 3C). The patient hasnot developed any clinical manifestations of hepatic dysfunction for 3years after diagnosis.DiscussionIn children with LCH, hepatic involvement is common.At presentation, hepatomegaly is observed in up to 60%of patients with disseminated LCH [3], but hepatomegalydoes not always portend a poor prognosis. Hepatic dysfunctionssuch as jaundice, hypoproteinemia, and portalhypertension may be present at the time of diagnosis ormay develop over months or years [1–3]. In all threepatients, clinical manifestation of hepatic dysfunction wasnot evident at the time of diagnosis.Morphologic changes of the liver in LCH have beendescribed in a number of previous studies. A reportfrom the Children’s Cancer Study Group has describedfour patterns: (a) portal triaditis with infiltrating neutrophils,eosinophils, or mononuclear cells; (b) bileduct proliferation with triaditis; (c) fibrohistiocyticchange; and (d) nodular parenchymal lesion with triaditis[1]. Other reports have described triaditis, periportalfibrosis, or liver cirrhosis and bile stasis and bileduct proliferation in some cases [2, 3, 9–11]. We couldnot confirm the sequential change of hepatic pathologyin each patient, but bile ductal proliferation and periductalinflammatory cell infiltration were noted in thepretreatment liver biopsy of patient 3. Biliary cirrhosisand extensive periductal fibrosis was seen in the explantedliver of patients 1 and 2, who had developedhepatic dysfunction. In patient 2, secondary sclerosingcholangitis was also noted.US finding of the liver in LCH has been describedas hypoechoic nodule or periportal hyperechogenicitythat may be attributed to inflammatory cell infiltrationor fat content [4, 5, 7, 8]. US in the present casesshowed periportal hypoechogenicity that was band-like