Like all other organs in the human body, the kidneys must be checked at all times in order to determine if there are any causes for concern. So naturally, many of us might wonder what a normal kidney size is, and what it means for our health.
What Is the Normal Kidney Size?
The average adult kidney size is around 10 to 12 cm which is roughly smaller than a clenched fist. But kidney size differs with age. To be more specific, refer to the bullet points below for the normal kidney size based on age group:
- Adult kidney size: 10-14 cm long for males and 9-13 cm long for females. The width ranges from 3-5 cm, 3 in antero-posterior thickness, and has a weight of 150-260 g. Usually, the left kidney is larger in size compared to the right kidney.
- Child kidney size: It depends on their age and size.
- 0 to 12 months: 5 cm
- 2 months to 6 months: 5.7 cm
- 6 months to 1 year: 6.2 cm
- 1 year to 5 years: 7.3 cm
- 5 years to 10 years: 8.5 cm
- 10 years to 15 years: 10 cm
- 15 years old and above: the kidney size for this particular age group is similar to the normal kidney size of adults.
Why Would a Kidney Shrink?
A shrinkage of a kidney is called kidney atrophy. Kidney atrophy happens for two main reasons:
- Congenital problem: the kidney does not fully develop since birth.
- The other reason happens after birth, and it can affect either one kidney or both kidneys. This happens when there is a low blood supply being sent to the kidney and/or the loss of nephrons.
Kidney atrophy also happens due to blockage and chronic infections. This shrinkage can lead to health issues such as kidney disease. And the more it decreases in size, the more severe the effects would be to the kidney. If both kidneys happen to shrink then that will lead to kidney failure.
Furthermore, small kidneys typically indicate an irreversible damage from a disease. In the Philippines, kidney shrinkage is commonly secondary to hypertension and diabetes, as well as long-standing kidney disease.
