Acute kidney injury (AKI) is a common complication in children with hematological malignancies. Although AKI due to infiltration of tumor cells in children is rare, it negatively impacts treatment outcomes and increases the risk of mortality. We introduce a case of a child with acute lymphoblastic leukemia (ALL) who experienced kidney relapse resulting in asymptomatic AKI after remission from treatment, to remind clinicians not to overlook the primary disease in clinical judgment. In cases of unexplained AKI, kidney biopsy should be performed when feasible to get an accurate diagnosis and scientific treatment. In brief, children with leukemia who have achieved remission after treatment still need regular monitoring of urine routine and kidney function.

急性肾损伤（AKI）是血液系统恶性肿瘤儿童的常见并发症。尽管儿童中由肿瘤细胞浸润引起的 AKI 很少见，但它会对治疗结果产生负面影响并增加死亡风险。我们介绍一例急性淋巴细胞白血病（ALL）患儿治疗缓解后出现肾脏复发导致无症状AKI的病例，提醒临床医生在临床判断时不要忽视原发病。对于不明原因的AKI，在可行的情况下应进行肾活检，以得到准确的诊断和科学的治疗。总之，治疗后病情缓解的白血病患儿仍需要定期监测尿常规和肾功能。