A diagnosis of an upper UTI is often supported by tenderness in which anatomical landmark?

A diagnosis of an upper urinary tract infection (UTI) is often supported by tenderness in the flank area because this region corresponds to the location of the kidneys and the ureters. Upper UTIs, which include pyelonephritis, involve inflammation of the kidneys, and patients typically experience pain or tenderness in the flank due to the irritation and inflammation of the renal tissues. This pain can also be exacerbated by movement or percussion over the area, providing further clinical support for the diagnosis.

In contrast, tenderness in the other areas, such as the pubic symphysis, mid-abdomen, or sacrum, may relate to different conditions or lower urinary tract infections rather than indicating an upper UTI. Therefore, the flank area is the most relevant anatomical landmark when considering the diagnosis of an upper urinary tract infection.