Full-Spectrum Kidney and Hypertension Services

The kidneys produce a hormone called erythropoietin (EPO), which signals your bone marrow to make red blood cells. As kidney function declines, less EPO is produced, leading to fewer red blood cells.

Red blood cell levels are measured with a blood test called hemoglobin (Hgb). When your hemoglobin falls below about 12, this is called anemia. Common symptoms include fatigue and shortness of breath, which are often more noticeable when hemoglobin drops below 10–11.

Your body naturally produces acid. The kidneys help balance this by producing substances that neutralize (buffer) acid and keep your body in a healthy range.

When the kidneys are not working well, they may not produce enough of these buffering substances, leading to a condition called acidosis. Symptoms can include fatigue, headache, shortness of breath, and a general feeling of discomfort.

The kidneys regulate how much fluid stays in your body. For example, when you are dehydrated, your kidneys conserve water by producing less urine. When you drink more fluids, they produce more urine to remove the excess.

As kidney function declines, this balance is disrupted, and your body may retain too much fluid. This often first appears as swelling in your feet and ankles, especially after standing. Over time, swelling can worsen and spread to the legs. In more advanced cases, fluid can build up in the lungs, causing shortness of breath.

The kidneys help activate vitamin D, which is essential for maintaining healthy bones and regulating calcium levels.

When kidney function declines, vitamin D activation decreases. This affects the parathyroid glands, which produce a hormone called PTH that controls calcium levels. As a result, you may develop bone weakness, pain, or an increased risk of fractures.

Calcium can also deposit in places it shouldn’t, such as blood vessels or heart valves, potentially increasing the risk of heart disease.

The kidneys control the levels of potassium and phosphate in your blood. When kidney function declines, these levels can become too high.

High potassium (hyperkalemia) can cause muscle weakness and may lead to dangerous heart rhythm problems.

High phosphate (hyperphosphatemia) disrupts the balance of calcium, vitamin D, and PTH, contributing to bone disease and increasing the risk of heart and blood vessel problems.

The kidneys help regulate blood pressure in two main ways: by controlling fluid levels and by releasing certain hormones.

When the kidneys are not working properly, excess fluid builds up in the body, including in the blood vessels, which raises blood pressure. The kidneys may also produce hormones that cause blood vessels to tighten, further increasing pressure.

This creates a cycle: high blood pressure damages the kidneys, and damaged kidneys make blood pressure worse.

One of the kidneys’ main jobs is to remove waste products from the blood. As kidney function declines, these wastes build up in the body.

When kidney function falls to about 10–15%, symptoms may develop, including nausea, vomiting, poor appetite, swelling in the legs, shortness of breath, itching, and difficulty concentrating.

If kidney function drops to very low levels (typically an eGFR below 15 for people with diabetes and below 10 for others), treatment is needed to replace kidney function. This may include a kidney transplant or dialysis. There are two main types of dialysis: hemodialysis and peritoneal dialysis.