A 65-year-old male was admitted to Peking Union Medical College Hospital. The patient had intermittent fever for 2 months with a maximum body temperature of 39.3 ℃ and elevated serum creatinine levels for 1 week. He had no other suggestive symptoms or positive signs. Laboratory test results suggested acute kidney injury and a sharp elevation in serum lactic dehydrogenase levels. Abdominal enhanced computed tomography (CT) revealed multiple low-density lesions, and further biopsy pathology demonstrated chronic inflammation. Thereafter, positron emission tomography (PET)/CT showed abnormally elevated uptake value for the bones throughout the entire body, in addition to the liver and brain. Repeated bone marrow biopsy finally confirmed metastatic bone cancer, which possibly originated from the kidney according to immunohistochemical staining. In this rare case of fever of unknown origin, the primary lesion was a renal tumor with bone, liver, and brain metastases. Enhanced CT and PET/CT provided negative results, and the diagnosis was eventually confirmed by repeated bone marrow pathology.
患者男，65岁，因间断发热2个月余，肌酐升高1周就诊。患者间断发热，体温最高39.3 ℃，入院后无其他伴随症状及阳性体征，伴急性肾损伤，外周血乳酸脱氢酶明显增高，尿常规正常，腹部增强CT发现肝多发低密度灶，肝穿刺活检病理提示慢性炎症。PET-CT显示全身骨、肝脏、脑摄取增高，多次骨髓活检病理确诊为骨转移癌，免疫组化标记物提示肾脏来源肿瘤。本例不明原因发热患者提示，虽然腹部增强CT及PET-CT均未发现肾脏病灶，依靠多次重复骨髓活检病理，明确诊断肾脏恶性肿瘤（骨、肝、脑转移）。.