These images were obtained from a middle-aged individual with a history of chronic kidney disease stage IV, smoking, and coronary artery disease, who was admitted for exacerbation of congestive heart failure. Upon initial inspection, numerous small hyperechoic structures are evident in both kidneys, accompanied by shadowing on greyscale images and twinkle artifact on color Doppler – typical of kidney stones. There is some ascites as well. However, the patient lacked prior kidney stone history, hypercalcemia, hyperparathyroidism, neurogenic bladder, etc., common risk factors for nephrolithiasis. Another potential diagnosis for multiple echogenic foci in the kidneys is air, indicative of emphysematous pyelonephritis. Nevertheless, the patient showed no symptoms or signs of infection, maintained good diabetic control, and had no recent urinary tract instrumentation.

Take a closer look again. Observe that those hyperechoic structures are linear, progressing toward the renal hilum as the transducer fans. Additionally, some of these structures display a double-lined appearance. Given the context of coronary artery disease and smoking, these are likely vascular calcifications. As expected, a CT scan revealed extensive calcifications in the abdominal aorta and its branches, along with intrarenal arteries.