Ultrasonography (US) plays a major diagnostic role in the pre- and post-transplant evaluation of recipient and donor. In most cases, US remains the only necessary imaging modality. After pediatric kidney transplantation, US can ensure immediate bedside diagnosis of vessel patency and possible postoperative non-vascular complications. Criteria for US diagnosis of kidney vessel thrombosis and stenosis in the transplant will be presented. Non-vascular complications after kidney transplantation include hydronephrosis, hematoma, lymphocele, and abscess. US can detect suggestive, but nevertheless non-specific, acute signs (sudden increase in volume and elevated resistive index), and chronic rejection, which therefore remains a histological diagnosis. US is of little or no help in detection of tubular necrosis or drug toxicity, but it can exclude other differential diagnoses. This educational review provides a practical and systematic approach to a multimodal US investigation of the kidney transplant. It includes a short overview on possible indications for contrast-enhanced ultrasonography (CEUS) in children after kidney transplantation.

超声检查 (US) 在接受者和供者的移植前和移植后评估中起着重要的诊断作用。在大多数情况下，US 仍然是唯一必要的成像方式。小儿肾移植后，超声可以确保立即床边诊断血管通畅和可能的术后非血管并发症。将介绍美国诊断移植肾血管血栓形成和狭窄的标准。肾移植后的非血管并发症包括肾积水、血肿、淋巴囊肿和脓肿。US 可以检测到提​​示性但非特异性的急性体征（体积突然增加和电阻指数升高）和慢性排斥反应，因此仍然是组织学诊断。US 在检测肾小管坏死或药物毒性方面几乎没有帮助，但它可以排除其他鉴别诊断。这篇教育综述为美国肾脏移植的多模式调查提供了一种实用且系统的方法。它包括对肾移植后儿童超声造影 (CEUS) 可能适应症的简短概述。