In clinical practice, creatinine 100 μmol/L is possible to be normal or abnormal. The normal range of blood creatinine varies depending on gender and laboratory and testing methods. If it does not exceed the upper limit of laboratory normal, it should be considered normal. If it exceeds the upper limit of normal it is abnormal and the causes are divided into physiological and pathological conditions. In the physiological condition, a mild increase in creatinine can generally occur with a large amount of meat consumption and exercise within three days, and it is recommended to review the test again after three days of a light diet. If the patient is still higher than normal after recheck, it is recommended to actively clarify the cause. The kidney has an obvious compensatory function, and creatinine will only be higher than normal when the kidney is damaged by 50% or more. The most common causes are obstructive nephropathy, glomerulonephritis, diabetic nephropathy, hypertensive kidney damage and vasculitis-related kidney damage, etc. You can check blood routine, urine routine, urinary ultrasound, rheumatism and immunity and other related examinations to clarify the cause and then actively treat the symptoms.