A 50year old man went to the emergency service with an unspecific abdominal pain complaint. We performed a multidetector computed tomography (MDCT) of the abdomen, with and without iodinated intravenous contrast, that showed a hypodense nodule formation with regular and well delimited outlines, few heterogeneous foci and fat density (-35 HU), sizing about 1.8cm from the inferior pole of the left kidney (Figure 1). The patient was relieved of the pain and was discharged from hospital in the same day. After a month, the patient returned to the emergency service with a worse abdominal pain and an altered hemodynamic state. We performed another MDCT of the abdomen which detected the same nodule spontaneously dense and larger, with 2.2cm. We also detected an extend subcapsular renal and retroperitoneal hematoma, all aspects related to a spontaneous renal bleeding (Figure 2). We choose a more conservative treatment with hemodynamic support and stabilization in an intensive care unit. The patient improved in the hemodynamic parameters, after a month of hospitalization and then hospital discharge, and remains in outpatient treatment with no complaints for 1year.
DiscussionThe display of fat in a kidney tumor by MDCT, as described in the case, is very suggestive of a RAML. 3 Other kidney tumors can also psent high levels of fat, such as the clear cell renal cell carcinoma, liposarcomas, atypical Wilms' tumor and teratomas. However, a cortical renal mass manly composed of fat (less than -20 HU) can be diagnosed as a RAML.
4-6Int J Radiol Radiat Ther. 2017;2(1):6-7.6