Kidney ultrasound is normal but high creatinine may be caused by physiological reasons such as muscularity or over-consumption of meat, or pathological factors such as kidney diseases. 1. Physiological reasons: creatinine can be elevated during strenuous exercise, excessive consumption of meat, or muscular exercise, creatinine will be higher than normal, usually no need to worry too much, and it can be gradually returned to normal after eliminating the triggers. 2. Pathological factors: high creatinine may indicate renal diseases such as drug-induced renal injury, glomerulonephritis, early diabetic nephropathy, etc.; or pyelonephritis and other urinary tract infections; at this time, creatinine increase occurs when renal function decreases, but the disease does not lead to morphological changes in the kidneys, so renal ultrasound did not see any abnormality. It is recommended that patients with abnormal creatinine should go to the hospital in time to improve the relevant examinations under the guidance of the doctor, and should actively cooperate with the doctor for treatment if it is caused by pathological factors to avoid the delay of the condition.