論文

We report the first case of a pancreatic desmoid tumor detected during follow-up for hemihypertrophy in a 4-year-old boy. Hemihypertrophy is a rare disorder in which one side of the body grows more than the other, causing asymmetry, and well-known complications include embryonal tumors. However, there has been no report of desmoid tumors in patients with hemihypertrophy, and these tumors are rare and poorly characterized in the literature, especially the cystic variant. For this patient, the lesion was diagnosed as a desmoid tumor based on immunostaining positive for beta-catenin and mutation of the beta-catenin gene (CTNNB1). This case suggests that desmoid tumors should be considered a possible etiology of pancreatic cystic lesions in patients with hemihypertrophy.

＜Key Points＞(1)原因疾患の診断よりも危急的な病態の評価を優先する。(2)第一に腹部単純X線写真と超音波検査を組み合わせる。(3)腹部単純X線写真ではガスの分布から病態や原疾患を判断する。(著者抄録)

＜Key Points＞(1)縦隔腫瘤では気道狭窄のリスクを念頭におく。(2)胸部単純X線撮影(正面、側面)にて腫瘤の位置、気道との関係、石灰化の有無など可能な情報をすべて読み取る。(3)CTもしくは造影CT撮影にて腫瘤の位置、周囲組織との関係、腫瘤の辺縁の状態、石灰化などを確認する。(4)制約はあるが、超音波、MRIともに診断に有用な情報を得られる。(著者抄録)

症例は在胎38週4日、体重2,755g、低置胎盤のため帝王切開にて出生した男児。生後鎖肛を指摘され、腹部単純X線にて巨大な腸管ガス像を認め、congenital pouch colon(以下、CPC)を疑われた。日齢1に開腹手術を施行し、嚢状に拡張した結腸と結腸膀胱瘻を認め、拡張結腸を温存して結腸膀胱瘻を切離し、断端で単孔式人工肛門を造設した。術後は温存した拡張結腸に便が貯留し、洗腸を要したものの体重増加は順調に得られた。根治手術目的に当院紹介となり、術前の注腸検査では拡張腸管の口側に上行・横行結腸を認め、Type 3 CPCと診断した。11ヵ月時に腹仙骨会陰式直腸肛門形成術を施行した。手術は拡張腸管を切除し、口側断端の結腸をpull throughした。術後の経過はおおむね順調であったが、排便機能に関してはこれまでの多くの報告と同様に良好とはいえず、薬剤や浣腸による排便管理を継続中である。(著者抄録)

BACKGROUND: Living donor liver transplantation in children often results in venous complications, leading to portal hypertension. Spleen stiffness measurements have been recently proposed as a new, noninvasive parameter for portal hypertension in cirrhotic patients. OBJECTIVE: To evaluate the diagnostic value of spleen stiffness measurements by acoustic radiation force impulse (ARFI) imaging in diagnosing venous complications after pediatric living donor liver transplantation. MATERIALS AND METHODS: We prospectively enrolled 69 patients after pediatric living donor liver transplantation using a left-side liver allograft. Around the time of the protocol liver biopsy examination, spleen stiffness measurements by ARFI imaging were performed via the left intercostal space at the center of the spleen parenchyma and repeated five times. Imaging examinations around the time of the spleen stiffness measurements were retrospectively reviewed. Regarding venous complications, significant portal and hepatic venous stenosis was defined as >50% stenosis on multiphasic computed tomography. RESULTS: After post hoc exclusion, 62 patients were studied. Portal and hepatic venous stenosis was identified in three and two patients, respectively. The median spleen stiffness values were 2.70 and 4.00 m/s in patients without and with venous complications, respectively (P < 0.001). Spleen stiffness measurements showed good diagnostic power for venous complications, and the cutoff value was determined as 2.93 m/s, with 100% sensitivity and 78.9% specificity. Spleen stiffness measurements decreased with the relief of venous stenosis resulting from an interventional radiology procedure. CONCLUSION: Spleen stiffness measurements by ARFI imaging might provide a useful quantitative index for venous complications after pediatric living donor liver transplantation.

Simpson-Golabi-Behmel症候群(以下SGBS)はglypican-3遺伝子(以下GPC3)変異によって発症する疾患で、過成長という身体的特徴を持ち、Wilms腫瘍や肝芽腫といった悪性腫瘍を高頻度に合併することが知られている。症例は身体的特徴からSGBSと診断された生後10ヵ月男児。経過観察中に血清AFP値の上昇を伴うPRETEXT病期IIIの肝腫瘍を指摘され、生検により肝芽腫と診断された。3ヵ月間の化学療法の後に、縮小した腫瘍の切除術を施行した。拡大右葉切除術(右三区域切除術)では残肝容量はわずかとなるため、中央二区域切除術を選択し、腫瘍は完全に切除された。本稿執筆時まで術後26ヵ月間、合併症、再発なく経過している。長期フォローアップによる再発、他種の腫瘍発症の評価を継続する方針である。(著者抄録)

OBJECTIVES: Most biliary atresia (BA) patients suffer from liver fibrosis and often require liver transplantation. The aim of this study was to develop and validate a novel fibrosis marker for BA patients aged <1 year-the infant BA liver fibrosis (iBALF) score-subsequent to the previously reported fibrosis marker for BA patients aged >/=1 year. METHODS: From three institutions for pediatric surgery, BA patients and their native liver histology examinations performed at the age of <1 year were retrospectively identified and assigned to a development cohort (58 patients and 73 examinations) or validation cohort (92 patients and 117 examinations) according to their institutions. Histological fibrosis stages (F0-F4), blood test results, and clinical information at the time of liver histology examination were reviewed. The iBALF score was determined using multivariate ordered logistic regression analysis and was assessed for its associations with histological fibrosis stages. RESULTS: The iBALF score equation was composed of natural logarithms, including serum total bilirubin level, blood platelet counts, and days of age. The score revealed a strong correlation with fibrosis stage (r=0.80 and 0.73 in the development and validation cohorts, respectively; P<0.001). The areas under the receiver-operating characteristic curves for diagnosing each fibrosis stage were 0.86-0.94 in the development cohort and 0.86-0.90 in the validation cohort (P<0.001), indicating good diagnostic power. In addition, no patient with an iBALF score >6 (equivalent to F4) at the initial surgery survived with their native liver at 1 year of age (n=9). CONCLUSIONS: The iBALF score that was developed was a good noninvasive marker of native liver fibrosis for BA patients aged <1 year.

Aim: Recent randomized trials have failed to prove the benefit of steroid-free immunosuppression in liver transplantation for hepatitis C virus (HCV)-related cirrhosis. Furthermore, there is a lack of data on the use of basiliximab in living donor liver transplantation (LDLT). This pilot study evaluated the safety and efficacy of a steroid minimization protocol using basiliximab compared with standard immunosuppression. Methods: A single center, prospective cohort analysis was conducted to compare two immunosuppression regimens in adult recipients who underwent LDLT for HCV since 2004: calcineurin inhibitor/mizoribine/basiliximab (the St- group) and calcineurin inhibitor/mizoribine/steroid (the St+ group). Study end-points were rejection rates, recurrent HCV, patient survival and other adverse events up to 2years after transplantation. Results: A total of 27 consecutive patients were enrolled. Transplantation characteristics were similar between the two groups (14 St- and 13 St+) except ABO incompatible cases being more common in the St+ group. Rejection rates, recurrent HCV, patient survival, fibrosis stage and new-onset diabetes mellitus at 2years were comparable between the two groups. ABO incompatibility did not affect short- and long-term outcomes. Nine St- and seven St+ recipients underwent interferon and ribavirin therapy for recurrent HCV, with a sustained virological response rate of 33% and 29%, respectively. Conclusion: A steroid minimization protocol with basiliximab in adult LDLT for HCV is safe and affords equivalent rejection rates compared with standard immunosuppression. However, no significant differences are observed with respect to recurrent HCV, patient survival and metabolic complications.

Lymphangiomatosis (recently renamed "generalized lymphatic anomaly") is a rare disease of unknown etiology that features an increase in the number of lymphatic vessels in many different tissues. Gorham-Stout disease(GSD) is a related disease characterized by lymphatic vessels involving the bones and resulting in progressive bone destruction. Respective definitions remain unclear because these conditions largely overlap in the clinical setting and are both associated with pleural effusion and other visceral lesions. These two conditions have recently been differentiated based on imaging findings. GSD is characterized by progressive osteolysis with loss of cortical bone. These diseases present considerable diagnostic and therapeutic challenges. Implementation of basic and clinical research is mandatory to improve understanding of these conditions and optimize management.

17歳男性。原因不明の肝硬変に対し生体部分肝移植術を行った(左葉グラフト、GRWR 1.05)。術後早期より胆汁うっ滞、凝固異常、多量の胸腹水、汎血球減少を認め、連日輸血を必要とした。移植後7日の肝生検で胆汁うっ滞と小葉中心性肝壊死を認めた。超音波検査にて肝動脈の流速低下、拍動係数上昇を認め、過小グラフト症候群に類似した病態を呈していると考え、移植後37日に近位脾動脈塞栓術を行ったところ肝動脈血流は著明に改善した。肝機能は徐々に改善し、移植後93日に軽快退院となった。過小グラフト症候群はグラフトのサイズが機能的な需要に対し不十分な状態で、門脈過還流が本態とされる。リスクが高い場合には予防的に脾摘や脾動脈結紮による門脈血流調節が行われる。本症例ではグラフト重量は充分で発症を予測できなかったが、診断的治療として血管造影、近位脾動脈塞栓術を施行し、低侵襲に状態を改善させることが可能であった。(著者抄録)

A 7-year-old boy undergoing home parenteral nutrition with totally implantable central venous access device for chronic intestinal pseudo-obstruction experienced repeated episodes of fever with a temperature above 39.0°C despite the antibiotic treatment. The fever was considered to be catheter-related blood stream infections, as no other etiology could be justified. Repeated blood culture tests revealed negative after 1-week incubation, whereas some samples of blood collected from the central venous catheter yielded positive and gram-positive rods were detected. These bacteria were detected repeatedly, then the central venous access device was removed with consideration for the possibility of this bacteria being a pathogen. Thereafter, the fever did not recur and the blood culture tests were negative. The causative agent was identified as Dermacoccus barathri based on the 16S rRNA gene sequence and phylogenetic analysis of 6118-bp concatenated sequences of 4 housekeeping genes. Genus Dermacoccus are one form of Actinomycetes isolated from human skin and water, but human infection with Dermacoccus spp. has not been previously reported and the pathogenicity of the bacteria remains unclear. To our knowledge, this is the first reported case of Dermacoccus infection in humans.

Background and aims: A number of genome-wide association studies have been performed as a robust means of identifying susceptibility loci for Crohn's disease (CD). The loci detected after the completion of the HapMap project are quite concordant among these studies, suggesting that the results are reliable. Recently, the Wellcome Trust Case Control Consortium (WTCCC) reported the primary scanning of 17 000 individuals for seven diseases, including CD, and a subsequent study has validated these susceptible genetic variants in independent UK sample sets. The purpose of this study was to study the possible association of the variants reported by the WTCCC with CD in a Japanese population. Patients and methods: A total of 484 patients with CD and 470 healthy controls were examined. Seventeen genetic variants at eight newly identified loci, including IRGM. NKX2-3 and PTPN2, were genotyped using the TaqMan assay or the invader assay. Results: A positive association signal presumably common to different ethnic groups for rs10883365 was detected in the upstream region of NKX2-3 (p = 0.019 under the genotypic model, p = 0.0065 under the allelic model, p = 0.019 under the recessive model, p = 0.036 under the dominant model). In addition to rs10883365, marginal associations for two single nucleotide polymorphisms (SNPs) were detected in the Japanese population; rs6887695 near IL12B and rs10761659 on 10q21. Further genotype-phenotype analysis found a significant association between rs6887695 and patients with pure ileal CD. Conclusions: The results indicate that the three loci are possible candidates for conferring susceptibility to CD in people of different ethnicities.

In vertebrates, the Müllerian duct elongates along the Wolffian duct, a mesonephric structure that is required for Müllerian duct formation. Recently, several genes required for initial Müllerian duct formation have been identified. However, the precise mechanism of Müllerian duct elongation remains to be elucidated. In this study, we investigated dynamic morphological changes in the elongating Müllerian duct in rat urogenital ridges in organ culture manipulated by microincision and/or chemical inhibitors. Mechanical division of the developing Müllerian duct showed that epithelial cells of the Müllerian duct actively migrate along the anterior-posterior axis independent of the proliferative expansion of the anterior portion of the duct. We found that the PI3K/AKT signaling pathway is activated in the Müllerian duct epithelium and is required for elongation of the tip of the duct; however, migration of Müllerian duct epithelial cells proximal to the tip remains intact when PI3K/AKT is inactivated. Although much is known about the molecular and cellular mechanisms leading to Müllerian duct regression, the present findings provide a fuller understanding of the mechanisms contributing to Müllerian duct formation and to the general process of early tubulogenesis. © 2008.