LRG1 and pulmonary artery-aorta diameter ratio measurement: Although no studies have evaluated the role of LRG1 in prerenal (due to hypovolemia or dehydration) or renal failure, it should be considered that the diagnostic yield of urinary LRG1 in the context of PAA may be confounded in 1) patients with undiagnosed pre-existing renal pathology, and 2) patients with prerenal failure due to dehydration.