Clinical implications of pediatric biliary intraepithelial neoplasia diagnosed from a choledochal cyst specimen.

BACKGROUND: Biliary intraepithelial neoplasia (BilIN), a noninvasive precursor of cholangiocarcinoma, can manifest malignant transformation. Since cholangiocarcinoma (CCA) may progress due to chronic inflammation in the bile ducts and gallbladder, choledochal cysts are considered a precursor to CCA. However, BilIN has rarely been reported in children, to date. METHODS: We reviewed medical records of patients (< 18 years of age, n = 329) who underwent choledochal cyst excision at Asan Medical Center from 2008 to 2022. BilIN was diagnosed in 15 patients. Subsequent analyses were performed of the demographics, surgical procedures, clinical course, and outcomes in these patients. Subgroup analysis and multivariate logistic regression test were performed to identify factors influencing BilIN occurrence. RESULTS: The mean age of the patients included in our study was 40.1 ± 47.6 months. In 15 patients, BilIN of various grades was diagnosed. Todani type I was prevalent in 80% of the patients. The median age at surgery was 17 months. During a mean follow-up of 63.3 ± 94.0 months, no adverse events such as stone formation in the remnant intrapancreatic common bile duct and intrahepatic duct or cholangiocarcinoma were observed, indicating a favorable outcome until now. CONCLUSIONS: The potential progression of choledochal cysts to BilIN in children was demonstrated. These results could underscore the importance of early and comprehensive excision of choledochal cysts, including resection margins for associated lesions and more thorough postoperative surveillance in patients with or at risk of BilIN.

Successful outcome with oral sirolimus treatment for complicated lymphatic malformations: a retrospective multicenter cohort study.

Purpose: Sirolimus has emerged as a safe and effective treatment for complicated lymphatic malformations (LMs). We aim to prove the effectiveness and safety of sirolimus as a therapeutic option for patients with complicated LMs. Methods: Fifty-eight patients with complicated LMs treated with sirolimus for at least 6 months at multicenter between July 2018 and January 2023 were enrolled. All patients were administered oral sirolimus starting at 0.8 mg/m2 every 12 hours, with target serum concentration levels of 8-15 ng/mL. Evaluation for clinical symptoms and LMs volume on MRI were reviewed to assess treatment response and toxicities. Evaluation of disease response was divided into 3 values: complete response, partial response (significant, moderate, and modest), and progressive disease. Results: The median age at the initiation of sirolimus treatment was 6.0 years (range, 1 month-26.7 years). The median duration of treatment was 2.0 years (range, 6 months-4.4 years). The most common lesions were head and neck (25 of 58, 43.1%). Forty-six patients (79.3%) demonstrated a reduction in LMs volume on MRI or improvement of clinical symptoms including 2 complete responses. The young age group and the patients who underwent few prior therapies showed better responses. None of the patients had toxicities attributable to sirolimus with a Common Terminology Criteria for Adverse Events grade of ≥3. Conclusion: Oral sirolimus treatment brought a successful outcome without severe adverse effects. It could be the first-line therapy, especially for the young age group of complicated LMs, and an additional option for refractory lesions that did not respond to conventional treatment.

The outcome of hiatal hernia repair and factors associated with surgical outcome in the pediatric population: a single-center experience.

Purpose: Hiatal hernia in children is a rare condition, and there is limited knowledge available about the disease itself. There is currently no agreement or consensus on the treatment of hiatal hernia in the pediatric population due to lack of evidence. In this study, we were to assess our experience with hiatal hernia, including the characteristics of our patients, surgical outcomes, and factors that influence the outcomes. Methods: We retrospectively reviewed the medical records of 49 patients below the age of 18 years who underwent hiatal hernia repair at the Asan Medical Center between 2006 and 2021. We analyzed and compared the general characteristics and surgical outcomes based on the presence of recurrence and coexisting congenital diseases. Results: Hiatal hernia progression was found to be associated with various medical conditions; however, no significant differences in patient characteristics or surgical outcomes between those with and without comorbidities were observed. There were no significant differences in patient characteristics or outcomes between the initial and redo operations. Fundoplication was performed in 19 patients (36.7%) during the initial operation and in 7 patients (87.5%) during repeat hiatal hernia repair. Conclusion: The presence of an underlying disease didn't influence the treatment and progression of hiatal hernia. Furthermore, there were no significant differences in the clinical course between patients with recurrent hiatal hernia and those experiencing it for the first time. Additionally, the impact of fundoplication on the recurrence of hiatal hernia in pediatric patients was found to be minimal.

Modified patch-conduit venoplasty for portal vein hypoplasia in pediatric liver transplantation.

Background: Portal vein (PV) interposition can induce various PV-related complications, making more reliable techniques necessary. The present study describes the development of a modified patch venoplasty technique, combining the native PV wall and a vein homograft conduit, called modified patch-conduit venoplasty (MPCV). Methods: The surgical technique for MPCV was optimized by simulation and applied to seven pediatric patients undergoing liver transplantation (LT) for biliary atresia combined with PV hypoplasia. Results: The simulation study revealed that inserting the whole-length native PV wall as a longitudinal rectangular patch was more effective in preventing PV conduit stenosis than the conventional technique using triangular partial insertion. These findings were used to develop the MPCV technique, in which the native PV wall was converted into a long rectangular patch, acting as a backbone for PV reconstruction. A longitudinal incision on the vein conduit converted the cylindrical vein into a large vein patch. The wall of the native PV was fully preserved as the posterior wall of the PV conduit, thus preventing longitudinal redundancy and unwanted rotation of the reconstructed PV. This technique was applied to seven patients with biliary atresia undergoing living-donor and deceased-donor split LT. None of these patients has experienced PV complications for up to 12 months after transplantation. Conclusions: This newly devised MCPV technique can replace conventional PV interposition. MCPV may be a surgical option for reliable PV reconstruction using fresh or cryopreserved vein homografts during pediatric LT.

Case report: Portal vein ligation: lessons from patients with PRETEXT III hepatoblastoma in restoring future liver remnant before major hepatectomy and literature review.

Background: We describe three cases involving three patients with PRETEXT III hepatoblastoma invading the hepatic hilum. After portal vein embolization, the patients underwent uncomplicated trisectionectomy. Methods: Medical records between March 2016 and March 2021 were reviewed, and three patients were selected. A literature review of techniques for increasing future liver remnant in children diagnosed with hepatoblastoma was also conducted. Results: All tumors involved the right lobe and hepatic hilum (PRETEXT III). After neoadjuvant chemotherapy, the tumor size decreased, but hilar involvement was unimproved. Right portal vein ligation (RPVL) was performed to increase the left lobe volume. Post-ligation, the remnant liver increased. Liver function was restored to normal levels within 5 days after the hepatectomy. All patients underwent two cycles of adjuvant chemotherapy without tumor recurrence. Conclusions: RPVL can be safely performed before extended hepatic resection in children with a giant hepatoblastoma invading the hepatic hilum. The tumor was completely resected by securing a sufficient margin and increasing the residual liver volume with portal vein embolization. The patients recovered and underwent adjuvant chemotherapy without the deterioration of liver function.

Redo pull-through for postoperative complications following pull-through in Hirschsprung disease: a single center experience.

Purpose: Although surgical management of Hirschsprung disease (HD) is effective in most patients, some patients experience long-term postoperative complications, and require redo pull-through (PT). The present study evaluated clinical outcomes of redo PT in HD patients at a single center. Methods: Patients with HD who underwent redo PT procedures between 2003 and 2019 were retrospectively reviewed. Results: Thirteen patients were included. Five (38.5%) had undergone initial PT surgery at our center and 8 (61.5%) at other centers. Redo PT procedures were transanal endorectal PT in 12 patients (92.3%) and the posterior sagittal approach in 1 patient (7.7%). Indications for redo PT included pathologic misdiagnosis in 8 patients (61.5%); stricture in 2 (15.4%); and rectal stenosis, obstructing Duhamel pouch and remnant septum in 1 each (7.7%). At a median follow-up of 68 months (range, 3-227 months) after redo PT, 8 patients (61.5%) had normal bowel function, 2 (15.4%) had incontinence, and 1 (7.7%) had constipation. Conclusion: Redo PT procedures could be an effective approach for improving obstructive symptoms in HD patients with anatomic or pathologic reasons following primary PT. Careful selection of patients and discreet indications for redo PT are crucial.

Optimal timing for inguinal hernia repair in premature infants: surgical issues for inguinal hernia in premature infants.

Purpose: We analyzed the timing of inguinal hernia repair in premature infants in the neonatal intensive care unit (NICU) considering recurrence, incarceration, and other complications. Methods: In this multicenter retrospective review, premature infants (<37 weeks) in the NICU diagnosed with inguinal hernia between 2017 and 2021 were segregated into 2 groups based on the timing of inguinal hernia repair. Results: Of 149 patients, 109 (73.2%) underwent inguinal hernia repair in the NICU and 40 (26.8%) after discharge. Preoperative incarceration did not differ, but complications with recurrence and postoperative respiratory insufficiency were higher in the NICU group (11.0% vs. 0%, P = 0.029; 22.0% vs. 5.0%, P = 0.01). Multivariate analysis showed that the significant factors affecting recurrence were preoperative ventilator dependence and body weight of <3,000 g at the time of surgery (odds ratio [OR], 16.89; 95% confidence interval [CI], 3.45-82.69; P < 0.01 and OR, 9.97; 95% CI, 1.03-95.92; P = 0.04). Conclusion: Our results suggest that when premature infants are diagnosed with inguinal hernia in the NICU, inguinal hernia repair after discharge may decrease the odds of recurrence and postoperative respiratory insufficiency. In patients who have difficulty delaying surgery, it is thought that surgery should be performed carefully in a ventilator preoperatively or weighed <3,000 g at the time of surgery.

Case report: Magnetic resonance imaging-based three-dimensional printing for reconstruction of complex cloacal malformations.

Background: Surgical reconstruction of the urinary tract, anus, and vagina is the definitive treatment for cloacal malformation. However, this procedure may be technically challenging in patients with a long common channel (>3 cm), because further reconstructive procedures, such as vaginal replacement or vaginal switch maneuver, may be required. Thus, accurate determination of spatial anatomy is essential during surgical planning. Three-dimensional (3D) reconstruction using rotational fluoroscopy, computed tomography (CT), and magnetic resonance imaging (MRI) has recently been reported to help in determining the relationship between the rectum, vagina, and bladder, and provides a more accurate measurement of the channel length compared to conventional cloacography. MRI-based 3D reconstruction provides substantial information regarding soft tissue structures around the cloaca, including the pelvic floor musculature and anus. Case: A 2-year-old girl with cloacal malformation required reconstructive surgery. Colostomy and cystostomy had been performed on the first day of her life. Preoperative loopogram revealed a cloaca with a long common channel (35 mm) and short urethra (9 mm), single vaginal opening in the bladder neck, and the colon anterior to the vagina with a fistula at the vaginal neck. Because the vagina was too short to be pulled through, 3D printing based on MRI was performed to visualize structural relationships prior to surgical correction. Saline was used for cloacal visualization. Furthermore, endoscopy-assisted urogenital mobilization was performed, and vaginal substitution was performed using the rectum. No postoperative complications were observed. Conclusions: We believe this is the first report of the use of MRI-based 3D imaging and printing, with saline as a contrast agent during surgical planning for correction of cloacal malformation. MRI-based 3D printing is a potentially promising technique for surgical planning of cloacal malformation correction in patients with a long common channel, as it provides detailed information about the surrounding soft tissue structures without exposure to radiation or contrasting agents.

Postnatal Imaging for Prediction of Outcome in Patients with Left-sided Congenital Diaphragmatic Hernia.

OBJECTIVE: To evaluate associations between postnatal imaging features and outcome of left-sided congenital diaphragmatic hernia, as defined by overall survival and a requirement for extracorporeal membrane oxygenation (ECMO). STUDY DESIGN: Newborns diagnosed prenatally with left-sided congenital diaphragmatic hernia between January 2013 and September 2021 were studied retrospectively. The esophageal deviation index was newly defined as the largest diameter from the midline to deviated gastric tube divided by the largest transverse diameter of the thoracic cavity on the radiograph. Regression analyses were performed to identify postnatal imaging features associated with overall survival and a requirement for ECMO. The predictive power (ie, area under the curve [AUC] of a time-dependent receiver operating characteristic curve) of prenatal, postnatal, and intraoperative findings for predicting survival were calculated. RESULTS: Ninety-seven patients (54 males; mean gestational age, 38.3 ± 1.9 weeks; mean birth weight, 2956.5 ± 540.0 g) were analyzed. The esophageal deviation index (adjusted hazard ratio [HR], moderate [≥0.19 to <0.24], 6.427 [P = .029]; severe [≥0.24], 33.007 [P < .001]) and right pneumothorax (adjusted HR, 8.763; P = .002) were associated with overall survival and with a requirement for ECMO. Liver herniation on postnatal ultrasound also was associated with overall survival (P < .001) and need for ECMO (P = .001). In addition, the AUC for prediction of 1-year survival from postnatal ultrasound was comparable with that of prenatally or intraoperatively detected liver herniation (0.93; 95% CI, 0.88-0.97). CONCLUSIONS: The esophageal deviation index, right pneumothorax, and liver herniation observed by postnatal imaging have prognostic value in patients with left-sided congenital diaphragmatic hernia.

Pediatric living donor liver transplantation for biliary embryonal rhabdomyosarcoma: a case report of a case showing disease-free survival over 2 years.

Biliary rhabdomyosarcoma is a rare tumor, but it is still the most common tumor of the biliary tract in children. We report a case of a 6-year-old boy with biliary embryonal rhabdomyosarcoma and liver metastasis, which were treated with neoadjuvant and adjuvant chemotherapy combined with living donor liver transplantation (LDLT). Initial imaging studies showed a low-attenuation intraductal mass from the left hepatic duct to the intrapancreatic common bile duct with diffuse upstream dilatation of the intrahepatic duct and liver metastasis. Endoscopic biopsy revealed embryonal rhabdomyosarcoma. After tumor size reduction through neoadjuvant chemotherapy, LDLT was planned to remove the tumor completely. A left lateral section graft weighing 330 g was harvested from his 38-year-old mother and the graft-to-recipient weight ratio was 1.94%. Routine pediatric LDLT operation was performed with deep excavation of intrapancreatic distal bile duct. The explant liver showed minimal residual embryonal rhabdomyosarcoma with no lymph node metastasis. The patient recovered uneventfully from LDLT operation. Scheduled adjuvant chemotherapy was performed for 6 months. The patient is doing well without any evidence of tumor recurrence for 26 months after LDLT. In conclusion, liver transplantation could be an effective treatment for unresectable biliary rhabdomyosarcoma in children according to the location of tumor.

Living donor liver transplantation in an infant patient with progressive familial intrahepatic cholestasis along with hepatocellular carcinoma: a case report.

Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease requiring liver transplantation (LT). Hepatocellular carcinoma (HCC) is very rare in infants. We present a case of living donor LT using a left lateral section graft performed in a 7-month-old female infant diagnosed with PFIC type II and HCC. No mutation on ABCB11 gene was identified. Because of progressive deterioration of liver function, living donor LT with her mother's left lateral section graft was performed. Pretransplant serum alpha-fetoprotein (AFP) level was increased to 2,740 ng/mL, but HCC was not taken into account because of its rarity. The explant liver showed micronodular liver cirrhosis, multiple infantile hemangiomas and two HCCs of 0.7 cm and 0.3 cm in size. The patient recovered uneventfully from the LT operation. This patient has been regularly followed up with abdomen ultrasonography and AFP measurement every 6 months. The patient has been continually doing well for 8 years after the LT. In conclusion, LT is currently the only effective treatment for PFIC-associated end-stage liver diseases. HCC can develop at the cirrhotic liver of any cause, thus elevation of HCC tumor markers in pediatric patients is an important clue to perform further investigation before LT.

Comparison of splenic vessel preserving distal pancreatectomy and the Warshaw technique for solid pseudopapillary neoplasm in children.

PURPOSE: Spleen-preserving distal pancreatectomy (SPDP) such as splenic vessel preservation (SVP) for solid pseudopapillary neoplasms (SPNs) in the body or tail of the pancreas in children prevents post-splenectomy infection and hematologic disorders. However, SVP could be technically challenging, and the Warshaw technique (WT) could be an alternative technique that has been reported to be safe and effective in adults. We, therefore, compared the perioperative outcomes of SVP and WT in pediatric patients. METHODS: We retrospectively reviewed the medical records of pediatric patients with SPN who underwent SPDP using SVP or WT between November 2002 and November 2018 at a large-sized tertiary referral center. RESULTS: Twenty-eight patients were included. Sixteen (57.1%) patients underwent SVP and 12 (42.9%) patients underwent WT. There were no significant differences in the baseline characteristics between the two groups. Postoperative complications occurred in 8 patients each in the SVP (50%), and the WT (66.7%) groups. Two (12.5%) in the SVP group and 1 (8.3%) in the WT group required additional intervention. During a median follow-up duration of 49 months, there were no significant differences in the incidence of splenic infarctions or perigastric varices between the two groups. CONCLUSIONS: There were no significant differences in the surgical outcomes between WT and SVP in pediatric patients with SPN. WT could be a safe and feasible alternative technique for SVP in challenging cases.

Liver transplantation in pediatric patients with progressive familial intrahepatic cholestasis: Single center experience of seven cases.

BACKGROUNDS/AIMS: Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease requiring liver transplantation (LT). The objective of this study was to investigate the clinicopathological features and posttransplant courses of seven LT recipients with PFIC. METHODS: This was a retrospective single-center study of patients with PFIC who underwent LT from January 2013 to June 2020. RESULTS: Two and five patients were diagnosed with PFIC type 1 and type 2, respectively. For all seven patients, age of PFIC onset was at birth. Jaundice was present in all cases. Mean pretransplant total and direct bilirubin levels were 16.1 ± 8.1 mg/dL and 12.4 ± 6.2 mg/dL, respectively. Median patient age and body weight at LT were 10 months and 7 kg, respectively. Types of donors were mothers of patients in four and deceased donors in three. All five patients with PFIC type 2 recovered uneventfully. One patient each with PFIC type 1 underwent retransplantation due to graft failure or died due to multi-organ failure. Overall graft and patient survival rates at five years were 66.7% and 83.3%, respectively. Bile salt export pump immunohistochemical staining showed normal canalicular expression in two patients with PFIC type 1, focal loss in two patients with PFIC type 2, and total loss in three patients with PFIC type 2. CONCLUSIONS: LT is currently the only effective treatment for PFIC-associated end-stage liver diseases. It is mandatory to perform regular follow-up due to the risk of complications including steatohepatitis, especially for patients with PFIC type 1.

Usability of intraoperative cine-portogram during liver transplantation in young pediatric patients with biliary atresia.

BACKGROUND: Pediatric patients with biliary atresia (BA) often present liver cirrhosis-associated portal hypertension and portal vein (PV) hypoplasia. For successful liver transplantation (LT), it is essential to maintain sufficient PV inflow through stenosis-free PV reconstruction with effective ligation of collateral veins. The aim of this study was to assess the clinical usability of intraoperative cine-portogram (IOCP) in young pediatric patients who underwent LT for BA. METHODS: Medical records of pediatric patients younger than 10 years who underwent primary LT for BA from 2018 to 2020 were reviewed. RESULTS: A total of 31 patients had undergone Kasai portoenterostomy soon after birth. Their median ages at Kasai portoenterostomy and LT were 1 and 11 months, respectively. Types of LT were living-donor LT in 13, deceased-donor split LT in 15, and deceased-donor whole LT in three patients. PV interposition using an iliac vein homograft was performed in 28 patients receiving partial liver grafts. Side-to-side PV unification venoplasty was performed in three patients undergoing whole LT. All patients underwent ligation of collateral veins. IOCP was performed in 6 (19.4%) patients. Four showed no or faint residual venous collaterals. Collateral vein embolization and endovascular stenting were performed in one patient each. PV insufficiency-free survival rate was 100% at 1 year and 93.8% at 3 years. All patients are currently alive with a median follow-up period of 23 months. CONCLUSIONS: Intraoperative cine-portogram can be a useful method for identification and embolization of residual portosystemic collateral veins in young pediatric patients who undergo LT for biliary atresia.

Living donor liver transplantation in a pediatric patient with congenital absence of the portal vein.

Congenital absence of the portal vein (CAPV) is a rare venous malformation in which mesenteric venous blood drains directly into the systemic circulation. We report a case of pediatric living donor liver transplantation (LDLT) for CAPV combined with focal nodular hyperplasia (FNH) and hepatocellular adenoma. A 9-year-old girl who had been diagnosed with multiple FNH had CAPV. Her blood ammonia level was raised to 137 µg/dL. However, she did not complain of any symptoms. To treat CAPV and FNH, we decided to perform LDLT. The graft was a left liver graft from 39-year-old mother of the patient. Recipient hepatectomy was performed according to standard procedures of pediatric LDLT. Portal vein reconstruction was performed using interposition of an iliac vein homograft conduit to the superior mesenteric vein-splenic vein confluence. The CAPV-associated congenital splenorenal shunt was securely ligated. The pathology report of the explant liver showed a 2 cm-sized hepatocellular adenoma and multiple FNH lesions measuring up to 7.1 cm. The patient recovered uneventfully from the LDLT operation. The reconstructed portal vein was maintained well without any hemodynamic abnormalities. In conclusion, as CAPV patients can have various vascular anomalies, combined vascular anomalies should be thoroughly assessed before and during liver transplantation operation. The most effective reconstruction techniques should be used to achieve satisfactory results following liver transplantation.

Funneling venoplasty for anomalous graft left hepatic vein in living donor liver transplantation using a split left lateral section graft for an infant patient.

The left lateral section (LLS) can have an unusual variant left hepatic vein (LHV) anatomy. We present a case of customized funneling venoplasty of the graft LHV in a 22-month-old girl diagnosed with ornithine transcarbamylase deficiency undergoing deceased donor liver transplantation (LT) using a split LLS graft. The split LLS graft weighed 350 g, yielding a graft-to-recipient weight ratio of 3.2%. Notably, the graft LHV opening was located at the graft liver cut surface, which was only 1 cm in size and 2 cm away from the cephalad apex of the LLS graft. Since such a variant location of the small LHV opening was unsuitable for direct anastomosis, we performed a funneling venoplasty using an inferior vena cava fragment homograft obtained from the same donor. The graft implantation was performed according to standard procedures of infant split LT. Follow-up imaging studies showed no vascular complications. The patient recovered uneventfully from the LT operation. She had normal blood test findings, including normal ammonia level. She has been doing well for 6 months after the transplantation. In conclusion, our surgical technique using a funneling venoplasty enabled successful reconstruction of the anomalous graft LHV. Our results suggest that individualized reconstruction techniques should be applied to infant patients undergoing LT using a LLS graft with variant types of graft LHV anatomy.

Dextroplantation of a reduced left lateral section graft in an infant undergoing living donor liver transplantation.

Graft size matching is essential for successful liver transplantation in infant recipients. We present our technique of graft dextroplantation used in an infant who underwent living donor liver transplantation (LDLT) using a reduced left lateral section (LLS) graft. The patient was an 11-month-old female infant weighing 7.8 kg with hepatoblastoma. She was partially responsive to systemic chemotherapy. Thus, LDLT was performed to treat the tumor. The living donor was a 34-year-old mother of the patient. After non-anatomical size reduction, the weight of the reduced LLS graft was 235 g, with a graft-to-recipient weight ratio of 3.0%. Recipient hepatectomy was performed according to the standard procedures of pediatric LDLT. At the beginning of graft implantation, the graft was temporarily placed at the abdomen to determine the implantation location. The graft portal vein was anastomosed with an interposed external iliac vein homograft. As the liver graft was not too large and it was partially accommodated in the right subphrenic fossa, thus the abdominal wall wound was primarily closed. The patient recovered uneventfully. An imaging study revealed deep accommodation of the graft within the right subphrenic fossa. The patient has been doing well for six months without any vascular complications. This case suggests that dextroplantation of a reduced LLS graft can be a useful technical option for LDLT in infant patients.

Efficacy and safety of autologous adipose tissue-derived stem cell therapy for children with refractory Crohn's complex fistula: a Phase IV clinical study.

PURPOSE: Autologous adipose tissue-derived stem cells (ASCs) have been proposed for patients with refractory Crohn disease, but research is lacking in pediatric patients. This Phase IV study evaluated the efficacy and safety of ASCs in children with refractory Crohn's fistulae. METHODS: Patients with a refractory Crohn's fistula who did not have conventional therapy for more than 3 months or with a recurrent complex Crohn's fistula were included. All patients were at least 14 years old. Patients with infection, poor condition, or active Crohn disease with a disease activity index of 450 and above were excluded. Five patients were treated with ASCs from 2014 to 2015 in Asan Medical Center. ASC administration was adjusted according to fistula size (1 mL per cm2). We evaluated the efficacy and safety 8 weeks after injection and followed patients for 6 months. RESULTS: Fistulae were healed in 4 patients by 8 weeks after ASC injection. Of these 4 patients, 1 had complete fistula closure and sustainability after 6 months. The other 3 with healing effects had less than 50% fistula closure by 6 months. None of these 4 patients have persistent fistulae. One patient had no healing effect, and seton ligation was performed 8 months after ASC injection. There were no adverse effects related to ASC administration. CONCLUSION: ASC therapy is a simple and well-tolerated therapeutic option for children with refractory Crohn's complex fistulae. Complete closure was well-sustained. However, more data from a larger number of patients are needed.

Third retransplantation using a whole liver graft for late graft failure from hepatic vein stent stenosis in a pediatric patient who underwent split liver retransplantation.

We present a case of third retransplantation using a whole liver graft in a 13-year-old girl who suffered graft failure and hepatopulmonary syndrome following split liver retransplantation with endovascular stenting of the hepatic and portal veins as an infant. She was diagnosed with biliary atresia-polysplenia syndrome, and thus underwent living donor liver transplantation from her mother at 9 months of age. The first liver graft failed due to stenosis of the portal vein. She underwent the second liver transplantation with a split left lateral section graft. Endovascular stenting was performed to the portal vein stenosis 2 months and hepatic vein stenosis 9 months after transplantation. During the next 9 years, 11 sessions of balloon angioplasty for hepatic vein stent stenosis were performed. Ten years after the second transplantation, she underwent third transplantation using a whole liver graft recovered from a 12-year-old-girl. The double inferior vena cava technique was used for outflow vein reconstruction. The graft portal vein was anastomosed with the stent-containing portal vein stump because it was not possible to remove the stent and the inner diameter of the portal vein stent was large enough. An aorto-hepatic jump graft was used for arterial reconstruction. The patient recovered slowly and is doing well for 6 months posttransplant. In conclusion, because stenting of the hepatic vein or portal vein can induce graft failure leading to late retransplantation, we emphasize secure vascular reconstruction to prevent endovascular stenting during LT in infants.

Effects of sirolimus in the treatment of unresectable infantile hemangioma and vascular malformations in children: A single-center experience.

OBJECTIVE: Recently, sirolimus has emerged as a safe and effective treatment modality for unresectable vascular lesions. In the present study, we investigated the effectiveness and safety of sirolimus from our early experience with patients with unresectable vascular anomalies. METHODS: The medical records and radiologic images of all patients with unresectable vascular anomalies treated with sirolimus at our center from January 2018 to November 2019 were retrospectively reviewed. All patients were administered oral doses of sirolimus 0.8 mg/m2 every 12 hours as the initial dose, followed by maintenance of a target serum concentration (5-10 ng/mL) with therapeutic drug monitoring. RESULTS: Six patients with unresectable vascular anomalies were treated with sirolimus for ≥10 months. Their median age at the initiation of sirolimus treatment was 17 months (range, 8-67 months). The median duration of treatment was 13 months (range, 10-16 months). One patient had a good response, four had an intermediate response, and one had no response to sirolimus therapy. None of the patients had discontinued sirolimus therapy because of adverse effects. CONCLUSIONS: Sirolimus can be used effectively and safely for patients with unresectable vascular anomalies. However, further prospective studies are warranted to evaluate the long-term effects of sirolimus and clarify the indications for early intervention.