肝脏移植术后胆道并发症的防治

目的探讨原位肝移植术后胆道并发症的防治方法。方法回顾性分析我院2002年6月至2006年9月完成的160例肝移植资料,其中行胆管-空肠Roux-en-Y吻合术10例、胆管-胆管端端吻合术150例。术后超声、CT、MRI、胆道造影和血清学检查了解移植肝形态、血流动力学及肝功能。98例随访2～48个月。结果发生胆道并发症24例（18%）,其中因肝动脉狭窄或栓塞引起的胆漏、胆道狭窄和肝内局限性坏死7例（5例经溶栓及内支架介入治疗后恢复、2例因肝功能衰竭并感染死亡）;胆道狭窄8例（6例经再次手术和ERCP及PTCD胆道内、外支撑等介入治疗恢复、2例胆管消融并发胆管炎死亡）;胆漏7例（6例经再次手术或超声引导下穿刺置管引流治愈、1例保守治愈）;胆道铸型2例（均经再次手术治愈）。结论供肝的质量和完整的动脉采集及胆道黏膜的保护,精细的动脉和胆管吻合是预防肝移植术后胆道并发症的关键。肝动脉溶栓、ERCP及PTCD胆道内支撑等是治疗胆道并发症的有效手段。     

肝移植术后胆道并发症的诊断与治疗

目的 探讨肝移植术后胆道并发症的诊断与治疗.方法 分析2007-2009年肝移植术后不同类型胆道并发症的患者的临床资料,评价胴道并发症的类型,处理方式及术后恢复情况.结果 肝移植术后胆道并发症患者23例,包括胆漏患者12例,计胆管吻合口漏7例,肝断面胆管漏3例,胆囊管漏1例,迷走胆管漏1例;移植术后胆管狭窄患者11例,其中吻合口狭窄4例,非吻合口性狭窄7例.7例吻合口漏患者中,胆管重建2例(Roux-en-Y吻合和胆肠襻式Warren吻合);胆道吻合口修补1例;单纯依靠外引流管引流1例,活体双供肝肝移植的患者剖腹探查纠正胆漏失败后行再次肝移植1例;行经内镜逆行胰胆管造影(endoscopic retrograde cholangiopancreatography,ERCP)植入支架2例.肝断面胆管漏3例中,行肝断面胆管缝扎1例,ERCP联合B超引导下穿刺引流2例,引流2个月后胆漏闭合,拔除引流管,但是随后又出现胆道狭窄,ERCP术后,病情好转.胆囊管漏1例,行胆囊管缝扎.迷走胆管漏1例,行胆囊床缝扎.吻合口狭窄的患者4例,3例经ERCP治愈,1例行胆肠吻合重建胆道后治愈.非吻合口性狭窄的7例,行ERCP治疗3例,ERCP失败后,行经皮肝穿刺胆管引流(percutaneous transhepatic cholangiographic drainage,PTCD)1例;再次肝移植3例,2例患者术后恢复良好,1例死于严重感染.结论 肝移植术后胆道并发症危害大,关键在于预防.     

原位肝移植术后胆管狭窄的诊断和治疗

目的探讨原位肝移植术后胆管狭窄的诊断和治疗方法。方法利用胆道内镜技术，对14例原位肝移植术后发生的胆管狭窄进行了诊断和分析；采取球囊扩张后支撑管支撑狭窄的方法进行治疗。结果经胆道造影和内镜综合诊断胆管吻合口狭窄13例（92．86％，其中1例是结石导致的狭窄假象）；非吻合口狭窄1例（进行了2次肝移植）。通过胆道造影明确诊断的4例吻合口狭窄中，1例采取球囊扩张1次治愈，2例行经内镜十二指肠乳头括约肌切开术＋网篮取石＋鼻胆引流术后仍然发生胆系感染和黄疸而行手术以及纤维胆道镜治疗，1例2次肝移植术后发生急性排斥反应而死亡。通过T型管造影，1例发现条状负影，无狭窄，纤维胆道镜观察胆管吻合口愈合佳，黏膜移行良好；2例肝内显影差或不显影而呈胆管消失改变，纤维胆道镜取净结石后，扩张吻合口的狭窄后用支撑管分别支撑3、4个月时狭窄消失，黏膜移行良好，拔管治愈；8例肝内外胆管显影模糊，肝外和肝内Ⅰ、Ⅱ级胆管有条索状、柱状、树枝状负影和非吻合性狭窄征象，纤维胆道镜观察取净结石后观察吻合口处均有不同程度的狭窄、充血水肿，扩张支撑平均2．5个月后，镜下观察狭窄消失，黏膜移行佳；1例造影提示吻合口狭窄，经扩张后，内镜观察未发现结石，支撑2个月后拔管治愈。结论应用胆道内镜诊断胆管狭窄直观可靠。胆道狭窄扩张支撑后拔管的标准为：T型管造影通畅无狭窄，内镜观察狭窄环消失，吻合口处黏膜移行。通过内镜技术治疗胆管狭窄具有微创、安全、有效和方便等优点。     

肝移植术后胆道并发症的预防与处理

回顾性研究20例原位肝移植的临床资料，并结合相关文献探讨原位肝移植术后胆道并发症的发生原因及防治措施。20 例患者中术后发生胆道并发症3例(15%) 。1例为术后1周内T管致胆管梗阻；1 例为术后3个月拔除T 管后胆漏，均经及时介入、置管引流而愈；1例为术后4个月弥漫性肝内外胆管狭窄经再次肝移植治愈。提示胆道并发症与留置T管、吻合等技术因素有关，而再灌注损伤、缺血性损伤是引起肝移植术后远期胆道并发症的重要原因。改进手术技术，缩短供肝缺血时间和确保供肝胆管系统的血供可减少胆道并发症的发生。     

肝移植术后胆道并发症危险因素和诊治分析

目的 探讨肝移植术后胆道并发症的相关因素及综合诊治经验.方法 回顾性分析2000年10月至2012年3月366例连续术后肝移植患者的临床资料.男性292例,女性72例,年龄18 ～69岁,平均年龄44.5岁.记录患者术后胆道并发症情况.采用单因素分析及Logistic多因素回归分析术后胆道并发症的危险因素.并发胆漏患者予置管充分引流.吻合口狭窄者经皮经肝胆道造影或经内镜逆行胰胆管造影行球囊成形术,必要时放置胆道支架;非吻合口狭窄者行经皮经肝胆道造影联合胆道镜治疗.结果 术后随访10 ～ 129个月,平均58.5个月,366例原位肝移植患者术后发生胆道并发症42例(11.5％).单因素分析及Logistic多因素回归分析结果示,第2次热缺血时间(门静脉血流复通到肝动脉血流复通的时间)、术中出血量和胆道吻合口直径与肝移植术后胆道并发症的发生相关(Wald=9.474～ 17.208,P＜0.05).12例胆漏患者通过腹腔引流、鼻胆管引流治愈;22例吻合口狭窄患者经内镜逆行胰胆管造影或经皮经肝胆道造影球囊成形术治愈,其中6例放置了胆道支架;8例非吻合口狭窄患者中,6例经皮经肝胆道造影联合胆道镜治疗后痊愈,1例接受二次肝移植后痊愈,1例恢复不良.结论 第2次热缺血时间、术中出血量和吻合口大小是肝移植术后胆道并发症的危险因素.肝移植术后胆管非弥漫性狭窄及胆漏的微创治疗安全、有效.     

原位肝移植后胆道并发症的诊断与治疗

目的 探讨原位肝移植术后胆道并发症的诊治。方法 回顾性分析40例原位肝移植的临床资料，总结术后胆道并发症的防治经验。结果 3例患者术后出现血胆红素和／或转氨酶持续性升高，经T管胆道造影术及核磁共振胆胰管成像证实存在胆道狭窄，其中2例为肝门部胆管与肝总管狭窄，1例为吻合口处胆管狭窄。经采用T管窦道球囊扩张术，3例的胆道狭窄得以改善，肝功能好转，其中1例经3次选择性球囊扩张，现健康存活已21月余；其中合并胆漏的1例，在B型超声波引导下穿刺置管负压引流后治愈；合并胆道胆泥淤积的1例及合并多重胆道感染的2例，均予以对症治疗。结论 手术技术不佳及胆管的血液供应不良是肝移植术后发生胆道并发症的重要因素；联合应用胆道造影术和核磁共振胆胰管成像能了解胆树全貌，有助于胆道狭窄、胆泥淤积与胆漏的诊断；及时采用放射介入技术处理胆道并发症可取得良好疗效。     

同种原位肝移植术的胆管重建及其术后并发症的防治

目的探讨同种原位肝移植(OLT)的胆管重建方式及其术后并发症的防治。方法回顾性分析1999年2月至2003年1月间103例终末期肝病患者施行OLT胆管重建及术后并发症的防治情况。103例患者中,75例采用经典式原位肝移植伴体外静脉转流、17例采用经典式原位肝移植不伴转流、11例采用背驮式原位肝移植。胆道重建过程中有94例行胆管端端吻合,9例行胆肠吻合。胆管端端吻合的患者中,62例带T管引流,32例不带T管,但11例经受者胆囊管置入小橡胶管引流。术后胆管并发症的诊断主要依据临床表现、B型超声波、磁共振胰胆管成像或逆行胰胆管造影检查。所有患者均随访1年以上。结果103例OLT患者术后胆管并发症发生率为7.8%(8/103)。62例带T管引流的患者中,6例(9.6%)发生胆管并发症,其中4例术后发生胆漏,2例拔除T管后发生局限性腹膜炎;32例不带T管引流的患者中,1例(3.1%)发生胆管狭窄。9例胆肠吻合中,1例(11.1%)术后发生胆漏。7例胆漏患者,2例经再次手术引流,其余继续保持引流胆漏自愈。不带T管引流的患者中的胆管狭窄为吻合口狭窄,经内镜取出异物、球囊扩张与安放内支架后治愈。1例患者因胆漏导致肝动脉吻合口假性动脉瘤及腹腔大出血,经介入法明确诊断并行栓塞治疗后治愈。患者中无胆管并发症而引起的死亡。结论胆管吻合口的胆漏与狭窄是OLT术后最常见的胆管并发症。良好的胆管血供与胆管吻合技术是防止胆管并发症发生的关键。及时的内镜检查与放射学技术是诊断和治疗胆管并发症的有效手段。     

降低肝移植术后手术技术相关胆道并发症的体会

目的 探讨肝移植的手术技巧，以降低手术相关胆道并发症。方法 对89例终末期肝病患者施行腔静脉成形的改良背驮式原位肝移植，供肝肝总动脉与受者肝总动脉端端吻合，供肝肝总管或胆总管与受者胆总管端端吻合，未置T管。术后定期进行影像学检查，了解移植肝是否出现胆道并发症。结果 1例术后5个月发生肝门分叉处胆管狭窄，经球囊扩张后效果不佳，再次手术行胆管狭窄成形术后治愈；其余患者未发生胆漏、吻合口狭窄、胆泥或胆道结石、肝门部胆管狭窄、胆管炎、胆汁瘤、粘液囊肿及十二指肠乳头功能异常等胆道并发症。结论 注重供肝的灌洗和修整，提高肝动脉吻合和胆道重建技巧，可有效避免或减少技术性胆道并发症的发生。     

原位肝移植术后胆道并发症的防治

目的　探讨原位肝移植术后胆道并发症的防治方法。方法　回顾性分析 1 3例原位肝移植中术后4例胆道并发症的临床资料 ,对其余 9例未发生胆道并发症的经验进行总结。结果　胆道并发症发生率30 .7% ,3例治愈 ,1例死于肝动脉血栓形成引起的胆总管吻合口漏。结论　早期胆漏常发生于吻合口 ,可采用胆总管重新吻合 (端端吻合或胆肠吻合 )治疗 ,手术操作中避免胆管缺血可有效预防吻合口漏。肝动脉血栓形成预后差。不放置T管可避免与T管有关的并发症。吻合口狭窄可采用介入治疗或手术治疗。     

胆肠吻合术在肝移植中的作用

目的 探讨胆肠Roux-en-Y吻合术在原位肝移植胆道重建以及术后胆道并发症治疗中的作用.方法 回顾性分析佛山市第一人民医院从2003年3月到2006年12月所实施28例原位肝移植胆道重建两种方式与术后并发症发生情况,胆管对端吻合组20例(占76.9%),胆肠吻合组8例(占23.1%),术后胆道并发症包括狭窄、胆漏、结石或胆泥以及广泛胆管坏死.结果 2例病人围手术期死亡,余26例病人总的胆道并发症发生率为19.2%(5/26),胆管对端吻合组发生率为27.8%(5/18),胆肠吻合组为0(0/8),胆肠吻合组胆道并发症发生率明显低于胆管对端吻合组(P<0.05),5例胆道并发症包括胆道狭窄3例,胆漏2例,治疗包括放置鼻胆管引流1例,放置金属内支架1例,行胆肠吻合术2例,行再次肝移植1例,其中2例死亡.结论 根据笔者的经验,胆肠Roux-en-Y术胆道并发症发生率明显低于胆管对端吻合组,无论是在肝移植胆道重建还是移植后胆道并发症处理方面,胆肠Roux-en-Y吻合术均非常有用,尤其是在重建胆管血运欠佳或内镜治疗失败时.     

劈离式肝移植术后胆管并发症

目的 探讨体外劈离式肝移植术后胆管并发症的危险因素及其防治措施.方法 2006年6月至2010年9月,我院共施行劈离式肝移植术33例,其中1例于术后10 d死亡,予以排除.其余32例患者中男性18例,女性14例,平均年龄33.4岁(6个月～65岁).胆管重建方式胆管端端吻合20例,胆肠吻合12例.胆管并发症的诊断依靠T管造影、经皮经肝胆管造影(PTC)、经内镜逆行胆胰管造影、磁共振胰胆管造影(MRCP)等方法.胆管并发症定义为存在需要外科、介入、内镜等方法治疗的胆漏或胆管狭窄.结果 受者中位随访时间13.5个月(3～54个月).32例患者中11例患者发生12次胆管并发症(37.5％),其中肝断面胆漏3例(9.3％),胆管吻合口漏4例(12.5％),左肝管残端漏1例(3.1％),胆管吻合口狭窄1例(3.1％),缺血性胆管狭窄3例(9.3％).8例发生胆漏的受者中6例经手术或穿刺放置引流后痊愈,2例因腹腔内感染死亡.单因素分析表明,移植物类型、胆管重建方式等均不是肝断面胆漏的危险因素.结论 与全肝移植和活体肝移植相比,劈离式肝移植术后胆管并发症尤其是胆漏更为常见.进一步防治胆管并发症是改善劈离式肝移植预后的重要因素.     

原位肝移植术后胆道结石的临床研究

目的 探讨原位肝移值术后胆道结石的诊治。方法 回顾性分析2000年1月至2003年1月完成的206例原位肝移值的临床资料，总结术后胆道结石的防治经验。结果11例病人术后并发胆道结石，发病率为5．3%。表现为颗粒样结石和胆泥两种形式。发生部位在胆总管者7例，在肝内胆道者1例。胆泥和颗粒样结石的首次诊断时间分别平均为138d和306d。胆道感染是胆道结石发作的主要症状。11例病例中有7例合并不同程度的胆道狭窄。主要依靠经“T”管照影或FRL、P(endoscopic reirograde cholangiopancreatography)术明确诊断。FRCP术是主要的非手术治疗手段，7例胆总管结石经1～3次ERCP术后痊愈。4例肝内胆道结石中合并弥漫性胆道狭窄者有3例，其中2例行再次肝移植术。结论 胆道狭窄是肝移植术后胆道结石的主要原因，胆道黏膜的缺血坏死合并胆道感染是胆泥形成的主要机制。ERCP术对胆总管绵石有良好疗效，对合并弥漫性胆道狭窄的肝内胆道结石病人肝脏再移值往往不可避免。     

Technique of bile duct reconstruction and management of biliary complications in right lobe living donor liver transplantation

From December 1999 to January 2002, 50 right lobe living donor liver transplantations were performed. The donor operations included an intraoperative cholangiography to elicit variations in bile duct anatomy. The biliary reconstruction was done whenever possible as an end-to-end microanastomosis of the donor right hepatic duct with the recipient's bile duct. As a result of the early segmental branching of the donor biliary tree, two segment bile ducts had to be anastomosed in 20 patients and three segment bile ducts in three patients. In 12 patients, a Roux-en-Y hepaticojejunostomy was performed. All anastomoses were drained externally. We observed two leakages at the resection surface which could be treated successfully by an external drainage. Six leaks occurred at the site of end-to-end biliary anastomoses. Twice the problem could be conservatively solved placing a stent percutaneously. In two patients a hepaticojejunostomy was performed after a bile duct necrosis. In two patients with an anastomotic leak, occurring 3 d, respectively, 3 month after the original transplantation, the bile duct could be directly reconstructed over a T-tube. Two anastomotic stenoses were observed, one in combination with a leak treated by percutaneous stent implantation and the second, 3 month after transplantation which was treated surgically. Biliary reconstruction after living donor liver transplantation requires microsurgical techniques and can be performed as a direct end-to-end anastomosis in most cases. Biliary complications were treated by percutaneous drainage or surgical revision in all cases.     

A prospective randomised trial of bile duct reconstruction at liver transplantation: T tube or no T tube?

A prospective randomised study of end-to-end bile duct reconstruction with or without T-tube drainage during orthotopic liver transplantation (OLT) was undertaken in 60 patients well matched for age, sex, aetiology of liver disease, operative blood loss, cold ischaemic time, preoperative serum bilirubin level and Child-Pugh score. Significant biliary complications in the T tube group occurred in five patients and included bile duct stricture (n=2), bile leak/peritonitis (n=1) and cholangitis (n=2). Bile duct strictures occurred in six patients in the no T tube group (P>0.05, NS). Hepatic artery stenosis was identified in one patient from each group in association with a biliary stricture. Biliary complications in both groups were associated with a prolonged graft cold ischaemic time (P<0.01). As no significant difference was noted in the number of early and late biliary complications between the two groups, the routine use of a T tube has been discontinued.     

The experience of biliary tract complications after liver transplantation

AIM: To report the morbidity and mortality of patients who undergo liver transplantation with or without T-tube implantation after choledochocholedochostomy as well as to discuss management of biliary complications. PATIENTS AND METHODS: We performed a retrospective review of 104 liver transplantations from August 2001 to February 2006, including 51 patients who underwent choledochocholedochostomy with a T-tube (group A) and 53, without a T-tube (group B). We compared the clinical characteristics, operative methods, biliary complications, morbidity, mortality, and management of complications. RESULTS: Between the two groups, there were no significant differences in clinical characteristics, including sex, age, and indication for liver transplantation (hepatitis B virus, hepatitis C virus, alcoholic liver cirrhosis, or hepatocellular carcinoma), Child-Pugh classification, Model for End-stage Liver Disease score, and operative macroscopic/microscopic findings. Additionally, there was no significant difference in biliary complications. Among these 104 patients, 14 (13.5%) developed biliary complications: seven anastomotic strictures, two intrahepatic duct strictures, two anastomotic stricture combined intrahepatic duct stricture, one bile leakage, one bile leakage combined with anastomotic stricture, and one external biliary compression. Nine patients with anastomotic stricture underwent endoscopy with a stent, which was successful only in two patients. The other six patients underwent choledochojejunostomy with excellent results. CONCLUSIONS: This study showed choledochocholedochostomy with or without a T-tube after liver transplantation did not influence the biliary complications. The biliary complications of anastomotic stricture after liver transplantation can be managed by endoscopy with a stent. If endoscopy fails, surgical intervention should be considered immediately.     

胆道镜在肝移植术后早期胆道内胆栓治疗中的应用

目的探讨胆道镜在肝移植术后早期胆道内胆栓治疗中的应用价值。方法31例原位肝移植,胆道重建采取胆总管端端吻合,并行T管引流,术后6～20周经T管造影提示胆道内结石形成,均伴有不同程度的肝功能异常。在进行胆道镜治疗前,采用16F外引流管经T管途径扩张及支撑窦道,1周后经窦道放入胆道镜达肝总管,用活检钳及取石网篮取出结石,逐级探查肝内胆道,必要时取活检组织,同时观察胆道吻合口、受者的胆道及Oddi括约肌情况。术后置入外引流管。结果除1例在扩张窦道过程中撕裂窦道外,其余病例均操作顺利,可完整取出胆树状铸型胆栓。31例中,22例(70.97%)治疗有效,术后肝功能基本恢复正常,拔除引流管后病情稳定;8例(25.81%)病情得到控制,术后肝功能基本恢复正常,拔除引流管后病情反复,需再次置入外引流管支撑;1例(3.22%)治疗后未见明显好转,病情进行性加重,接受再次肝移植。结论胆道镜下可直观了解胆道情况,解除胆道梗阻,可作为治疗肝移植术后早期胆道内胆栓的一种手段。     

肝移植术后胆道狭窄的临床特点及治疗效果(附60例报告)

目的 探讨肝移植术后并发胆道狭窄的临床特点及治疗效果.方法 回顾性分析60例肝移植术后胆道狭窄患者的临床资料.并对其临床特点和治疗效果进行了分析和讨论.结果 肝移植术后胆道狭窄的主要症状为胆道梗阻和胆管炎表现.其平均诊断时间为术后(195.5±146.5)d.胆道狭窄早期,肝功能损害主要为血清丙氨酸转氨酶、总胆红素、谷氨酰转肽酶及碱性磷酸酶水平升高,而白蛋白降低;胆道狭窄晚期时,丙氨酸转氨酶水平下降,出现"胆酶分离"现象.经内窥镜逆行胰胆管造影(ERCP)检查发现,胆道狭窄部位为单纯吻合口狭窄6例;肝门部和/或合并吻合口狭窄11例;肝内胆管弥漫性狭窄11例;吻合口合并肝内胆管弥漫性/节段性狭窄32例.其它并发症还包括胆管内有异物、狭窄近端扩张、胆管扭曲及十二指肠乳头旁憩室等.经ERCP介入治疗,取出胆管内异物、坏死组织、结石以及狭窄段球囊扩张等处理后,33例患者治愈,18例好转,9例治疗无效.结论 肝移植术后胆道狭窄的临床表现既有特征性,又有多样性,且合并症较多;采用ERCP介入治疗胆道狭窄效果理想.     

原位肝移植术后胆道并发症治疗经验

目的总结原位肝移植术后胆道并发症的治疗经验。方法1999年2月至2004年2月,我中心采用胆总管-胆总管端端吻合术施行原位肝移植236例,96例采用置“T”管引流的胆管间断吻合;39例采用未置“T”管的胆管间断吻合技术;101例采用未置“T”管、前壁间断后壁连续的胆管吻合。结果全组术后32例(13·3%)发生胆道并发症,其中胆管狭窄24例(10·0%),胆漏6例(2·5%),胆管结石2例(0·8%)。3组胆道并发症发生率分别为17·7%、15·4%和7·9%,其中肝门部/肝内胆管狭窄发生率分别为8·3%,2·6%和1·0%。第3组胆道并发症发生率和胆管狭窄发生率显著降低(P<0·05)。20例胆管狭窄患者接受放射和/或内镜介入治疗,其中单纯吻合口狭窄治愈率90%,肝门部/肝内胆管狭窄治愈率60%。结论弃用“T”管的胆管前壁间断后壁连续的吻合方式能显著减少胆道并发症;非缺血相关性胆管吻合口狭窄和单纯肝门部胆管狭窄应首选介入治疗。     

Role of magnetic resonance imaging in the detection of anastomotic biliary strictures after liver transplantation

Introduction

Biliary complications after orthotopic liver transplantation (OLT) are the principal cause of morbidity and graft dysfunction, ranging in incidence from 5.8% to 30% of cases. Biliary strictures are the most frequent type of late complication. The aim of this study was to evaluate the role of magnetic resonance cholangiography (MRC) to detect biliary anastomotic strictures among patients undergone OLT with abnormal liver function tests.

Materials and methods

One hundred twenty-one of 300 patients who underwent OLT were evaluated by MRC for clinically suspected anastomotic biliary strictures. In all patients, we performed various precholangiographic sequences including T1- and T2-weighted and MRC (radial SE 2D and SS-TSE 3D). Magnetic resonance imaging findings were subdivided as absence or presence of an anastomotic stricture. Diagnostic confirmation was obtained by endoscopic retrograde cholangiography (n = 32), percutaneous transhepatic cholangiography (n = 21) or surgical treatment (n = 18).

Results

MRC detected 56 anastomotic biliary strictures, 53 of which were confirmed by other imaging modalities. MRC showed two false-negative cases and three false-positive cases. The sensitivity, specificity, positive and negative predictive values, and accuracy of MRC to detect biliary strictures were 96%, 96%, 95%, 97%, and 96%, respectively.

Conclusion

MRC proved to be a reliable noninvasive technique to visualize the biliary anastomosis and depict biliary strictures after OLT. MRC should be used when a biliary anastomotic stricture is suspected in an OLT patient.