Understanding Enlarged Kidneys: Causes and Related Conditions

When our ancestors evolved, they didn't just develop one of everything; they developed two. This bilateral symmetry is how we evolved, with two eyes, two arms, two legs, and two lungs. While it isn't ideal to have two brains, it is comforting to know that if one kidney fails, we have another.

Why do we have two kidneys instead of one large one?

According to evolutionary theory, the reason for having two kidneys, rather than one, is simple: redundancy. If you have two kidneys, you can function and live a normal life even if one of them stops working. This redundancy is crucial because it allows the body to maintain its critical functions during medical emergencies.

Normal Kidney Size and Enlargement

The normal size of kidneys is around 4-5 inches in length (10 to 12 cm). Kidney enlargement, or hydronephrosis, is a medical condition that can be caused by underlying diseases. This condition can be serious and requires medical attention.

Causes of Enlarged Kidneys

Polycystic Kidney Disease

One of the most common causes of kidney enlargement is Polycystic Kidney Disease (PKD). This is a genetic disorder that causes multiple cysts to grow within the kidneys. As these fluid-filled cysts expand, they can cause the kidneys to enlarge. People with PKD often experience symptoms such as back pain, high blood pressure, frequent urination, and swelling. If left untreated, PKD can lead to kidney failure.

Kidney Stones

The development of kidney stones inside the kidneys can also cause them to grow, leading to kidney enlargement. Kidney stones can grow very large and cause painful symptoms, including frequent and painful urination, nausea, fever, and pain in the back, abdomen, or sides.

Unilateral Hydronephrosis

Unilateral hydronephrosis is another cause of kidney enlargement. This condition involves kidney swelling due to backed-up urine. It is often a result of a more serious problem, such as an obstruction in the urinary tract or a tumor on the bladder. In addition to the enlarged kidney, abdominal masses may also be present in individuals with this condition.

Factors Leading to One Kidney Being Larger Than the Other

From my experience, it's not unusual to see kidneys that are not exactly the same size. However, there are conditions that can cause one kidney to be significantly larger than the other. These include infections, a faulty drainage system, and other underlying issues. It's important to consult with a doctor regarding your concerns. If you experience symptoms such as increased or decreased urination, swelling in your legs or extremities, or blood in your urine, you should seek medical attention immediately.

Conclusion

In conclusion, while having two kidneys provides redundancy and improved health outcomes, there are various conditions that can cause one kidney to be larger than the other or for both kidneys to enlarge. It's essential to be aware of the symptoms and seek medical advice if you are concerned about any abnormalities in your kidney function.