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Katsuhiro Asonuma

Publications and source records attributed to Katsuhiro Asonuma.

12 recordsLinked to original sources

Ectopic cervical thymus in an infant.

We report a case of accessory cervical thymus presenting as a unilateral neck mass in a 2-month-old boy. Ultrasonography (US) showed a mass isoechogenic to muscle in the left neck. Computed tomography (CT) revealed a well-defined, mildly enhanced mass located anterior to the sternocleidomastoid muscle, anterolateral to the carotid sheath, and posterior to the submandibular gland. On magnetic resonance imaging (MRI), the mass was isointense to muscle on T1-weighted images and hyperintense to muscle on T2-weighted images. Diffusion-weighted images showed relatively low apparent diffusion coefficient (ADC) values, and the mass was slightly enhanced after administration of contrast material. We suspected ectopic thymus, but we could not exclude the possibility of a malignant lesion. Therefore, the tumor was surgically resected. The histological diagnosis was ectopic cervical thymus. Ectopic thymus should be included in the differential diagnosis of a submandibular or cervical mass in infants. US and MRI can provide useful information for the diagnosis of ectopic cervical thymus.

Biomarkers, Tumor↗

Effect of tacrolimus and partial hepatectomy on transthyretin metabolism in rats.

Liver transplantation, which serves as treatment of familial amyloidotic polyneuropathy (FAP), and domino liver transplantation, which utilizes resected livers from patients with FAP for treatment of liver diseases, may induce changes in transthyretin (TTR), a pathogenic FAP-related protein. To evaluate this possibility, we performed a 70% hepatectomy or administered tacrolimus to Dark Agouti (DA) rats for 7 days and then measured changes in liver TTR mRNA levels and changes in serum TTR concentrations. After hepatectomy, TTR mRNA levels decreased by 77%; at day 3, they returned to preoperative levels. Except for slightly elevated serum TTR concentrations 12 h after operation, serum TTR levels remained unchanged. Thus, partial hepatectomy did not influence serum TTR concentrations. After tacrolimus administration, TTR mRNA declined by 56% 12 h after the experiment started; however, after day 3, a rebound phenomenon occurred until day 7. Tacrolimus may facilitate serum TTR degradation, although production of TTR in the liver also increased. This finding -- that TTR, the source of FAP-inducing amyloid, did not increase after transplantation -- may help post-transplantation treatment of patients who have FAP and other liver diseases.

Animals↗

Feasibility of using the cystic duct for biliary reconstruction in right-lobe living donor liver transplantation.

Duct-to-duct biliary reconstruction has been introduced in adult living donor liver transplantation (LDLT). In right-lobe grafts, however, the presence of two or three separated bile duct orifices is not rare and makes an alternative approach for reconstruction necessary. We used the cystic duct for one of the anastomoses in biliary reconstruction for 5 right-lobe living donor liver transplants with two separated ducts. Before the anastomosis, the inside lumen of the cystic duct was straightened with a metal probe. Two external drainage tubes were placed in all recipients, and posttransplant cholangiography through the tubes approximately one month after transplantation showed no leakage or stricture at any of the anastomotic sites. The drainage tubes were removed between 17 and 37 weeks after transplantation. All of the patients except one who died of chronic rejection have been doing well without any late biliary complications during follow-up periods ranging from 10 to 28 months after transplantation. In conclusion, our results indicate that biliary reconstruction using the cystic duct is feasible and safe for living donor liver transplantation and that external drainage tubes may be effective for prevention of complications.

Adolescent↗

Living domino liver transplantation in an adult with congenital absence of portal vein.

Congenital absence of the portal vein (CAPV) is a rare malformation of the splanchnic venous system. Although CAPV is usually detected in the pediatric age group, our patient was a 35-year-old woman. She had been diagnosed with CAPV in 1996 when she was 27 years old. In 1998, she was placed on hemodialysis due to chronic renal failure. After several episodes of encephalopathy in 2002, liver transplantation (LT) was recommended to her and her family. Since there was no suitable living donor candidate, she was put on the waiting list for a deceased donor liver transplant in Japan. In 2004, her ammonia level increased to around 300 microg/dl, and she went into a coma lasting for three days. After recovering from this event, she underwent a living domino transplantation using a whole liver donated by a familial amyloid polyneuropathy (FAP) patient. Her portal vein, which had drained directly into the inferior vena cava (IVC), was transected together with a cuff of the IVC wall and anastomosed to the graft liver portal vein in an end-to-end fashion. In conclusion, liver transplantation proved to be a safe and effective way to save this patient and improve her quality of life.

Adult↗

Duct-to-duct biliary reconstruction in pediatric living donor liver transplantation.

The results of duct-to-duct biliary reconstruction in six pediatric patients who received a living donor liver transplant aged from 2 months to 11 yr old are reported. The graft was either entire or a part of the left lateral segments. The orifice of the bile duct of the graft was anastomosed to the recipients' hepatic duct in an end-to-end fashion by interrupted suture using 6-0 absorbable material. A transanastomotic external stent tube (4 Fr) was passed through the stump of the recipients' cystic duct. Mean time for reconstruction was 24 min. All the recipients survived the operation and reinitiated oral intake on postoperative day 3. There were no early biliary complications. One 5-yr-old boy suffered from an anastomotic stenosis 9 months after transplantation. He underwent re-anastomosis by Roux-en Y (R-Y) procedure and recovered uneventfully. Duct-to-duct anastomosis in pediatric living donor liver transplantation has benefits while the complication rate is comparable to R-Y reconstruction.

Anastomosis, Surgical↗

[Practical application of nutritional assessment protein and inflammatory marker in the nutrition support team (NST)].

Recently nutrition support team (NST) has been established for the purpose of prevention of complications which are caused by nutrition disorders and reduction of the medical expenses. Although physical examinations and blood biochemical data had been used as the indexes evaluating nutritional of patients, they were not suitable for the evaluation for the short-term in-patient. On the contrary, serum albumin (ALB) has been wildly used as a nutritional marker. However, it is impossible to evaluate nutrition state for the short-term in-patient and acute phase disease patient accurately, because the plasma half-life is 21 days and it takes long time to detect the change in nutritional state by its value. Rapid turnover proteins (RTP), whose plasma half-life is shorter, has paid attention to evaluate nutritional state for the short-term in-patients and acute phase disease patients. Although, prognostic inflammatory and nutritional index (PINI) was considered as a useful maker for evaluating inflammatory and nutritional states using the concentrations of transthyretin (TTR), a RTP, alpha1-acid glycoprotein (alpha1-AG), a chronic inflammation marker, C reactive protein (CRP), a acute inflammation marker, and ALB, However, it has several pitfalls. We newly made serum amyloid A (SAA) index using SAA instead of CRP. When we compared SAA index with PINI in many diseases, it turned out that SAA index became a more effective index which reflected the patient condition than did PINI. As for this index, it is expected to be used by NST while further alternation may be needed.

C-Reactive Protein↗

Rescue for rare complications of the hepatic artery in living donor liver transplantation using grafts of autologous inferior mesenteric artery.

This report describes two rescued cases with rare complications of the hepatic artery in living-donor liver transplantation (LDLT). In both cases a segment of the autologous inferior mesenteric artery (IMA) was successfully used as an arterial graft for re-vascularization under microsurgery. The first case was that of a pseudoaneurysm of the hepatic artery, which caused massive gastrointestinal bleeding. The hepatic arteries of the pre- and post-aneurysm were divided, and the arterial graft from the recipient's IMA was interposed for reconstruction. The second case was that of an intimal dissection of the recipient's hepatic artery. Because the dissection extended to the root of the common hepatic artery, the autologous IMA was interposed between the donor's hepatic artery and the proximal stump of the recipient's splenic artery. Reconstruction using the arterial graft of the autologous IMA is feasible for re-vascularization of the hepatic artery in liver transplantation.

Adult↗

Early graft failure due to a veno-occlusive disease after a pediatric living donor liver transplantation.

A 10-month-old boy with biliary atresia after Kasai procedure underwent a living donor liver transplantation (LDLT). Five days after the LDLT, high fever and increased ascites followed by poor bile drainage was accompanied by elevation of serum liver enzymes. Liver biopsy showed occlusion of the central veins by fibro-edematous endothelium and submassive necrosis of the parenchyma. Veno-occlusive disease (VOD) was suspected, and re-LDLT was urgently performed because of deterioration of hepatic failure. There are few cases of VOD after liver transplantation and this is the first one in an infant after LDLT.

Graft Occlusion, Vascular↗

Long-term effects of liver transplantation on bone mineral density in children with end-stage liver disease: a 2-year prospective study.

In children with end-stage liver disease, little is known regarding the long-term effects of liver transplantation on bone. In this 2-year prospective study, we evaluated the effects of liver transplantation on bone mineral density (BMD) and on other parameters of bone metabolism in 30 consecutive children with biliary atresia who underwent liver transplantation after failed Kasai operation. Tacrolimus and steroids were used as immunosuppressants. BMD of the first through fourth lumbar spine (L1-4) was measured by dual-energy radiographic absorptiometry (QDR-2000, Hologic) and expressed in Z-values. Before transplantation, Z-values of BMD, height, and weight were low in all patients (-3.4 +/- 0.34, -2.0 +/- 0.28, and -1.67 +/- O.16 [mean +/- SEM], respectively). Low BMD states were associated with low levels of serum 25-hydroxyvitamin D and serum levels of insulin-like growth factor-I (IGF-I), one of the most potent anabolic skeletal growth factors. Liver transplantation resulted in marked improvement in BMD values as well as in height and body weight: 24 months after transplantation, recovery was achieved in each parameter (0.16 +/- 0.30, -0.29 +/- 0.23, and 0.42 +/- 0.18, respectively). BMD recovery first was observed 3 months after transplantation. Moreover, these favorable effects of transplantation were accompanied by increases in serum levels of 25-hydroxyvitamin D and IGF-I. We conclude that liver transplantation effectively reverses the low bone mass status and growth retardation of children with end-stage liver disease.

Adolescent↗

Compressed spectral arrays of patients with fulminant hepatic failure in hepatic coma undergoing liver transplantation.

Assessing the coma status of patients with fulminant hepatic failure (FHF) is important for determining the reversibility of brain damage and for properly timing liver transplantation. The compressed spectral array (CSA) method is a frequency analysis technique that processes electroencephalogram signals by computer to facilitate on-line interpretation. This method has been used to monitor the consciousness levels of neurointensive care unit patients. In this study, we determined whether CSA could be used to assess the coma status of patients with FHF, and whether CSA provided information that was useful in deciding when to proceed with liver transplantation. CSA recording was carried out in 17 FHF patients with encephalopathy (coma grade III-IV) who underwent living-related liver transplantation between August 1997 and May 1999. Recording was performed with a Neuromonitor OEE-72044 (NIHON KOHDEN, Osaka, Japan) every 24 h before and after transplantation, until the patients regained consciousness. The CSAs of healthy controls were distributed almost equally between 0 and 16 Hz. The CSAs of FHF patients in hepatic coma were classified into three patterns. Eight of the 17 patients showed very prominent slow waves of about 2 Hz (group A), and seven patients showed strongly suppressed rapid waves between 8 and 16 Hz (group B). The remaining two patients showed CSA patterns that were similar to those of healthy controls, even though these patients were comatose (group C). Abnormal CSA patterns were observed in 15 of the 17 patients (88%). Group B patients seemed to have higher coma grades than did group A patients. Sixteen patients underwent liver transplantation, completely recovered from hepatic encephalopathy, and subsequently showed CSA patterns similar to those of healthy controls. One patient died without regaining consciousness. These results suggest that CSA is useful in assessing the coma status of FHF patients and in evaluating electrophysiological recovery from hepatic coma after liver transplantation.

Adolescent↗