Pain in the right flank with high fever and raised infection parameters
Although a mass in the kidney is always suspicious for a renal cell carcinoma, in this case the aspect of the mass and the clinical findings were more suggestive for a focal pyelonephritis with abscess formation. The follow up confirmed this diagnosis.
References
Vourganti S, Agarwal PK, Bodner DR, Dogra VS. Ultrasonographic evaluation of renal infections.Radiol Clin North Am. 2006 Nov;44(6):763-75. Review.