Nephrology: Understanding the kidneys

The kidneys serve as essential organs that play an important role in the general health and well-being of the body. They are in charge of filtering and eliminating waste materials from the blood, as well as regulating fluid and electrolyte balance. Nephrology is a subspecialty of medicine concerned with the study of the kidneys and how they function. In the modern world, where chronic illnesses are on the rise, the function of Nephrology in the healthcare system is becoming increasingly important. 

What is Nephrology?

Nephrology refers to the study of the kidneys and related disorders that affect their functions. The treatment of chronic kidney disease, kidney stones, glomerulonephritis, and urinary tract infections all fall under Nephrology.

What are the functions of the kidneys?

The renal system includes a pair of bean-shaped organs called kidneys. They assist the body in excreting waste in the form of urine. They are also helpful in filtering blood and sending it back to the heart.

The kidneys carry out several essential functions of the body, which may include the following.

• They help maintain the total fluid balance in the body

• They filter and maintain a healthy balance of minerals in the blood

• They filter out waste materials, extra fluid, and toxic substances from the body

• They produce hormones that help in the production of red blood cells, manage bone health, and regulate blood pressure

Symptoms of kidney disease

Kidney diseases may exhibit various symptoms. Among them, the most common symptoms may include the following.

• Having difficulty sleeping

• Muscles cramping

• Bloody and frothy urine

• Tiredness and fatigue

• Changes in urination

• Ankle and foot edema

• Loss of appetite

• Persistent pruritus

• Swelling near the eye area

• Difficulty concentrating

Tests to diagnose kidney disease

If your doctor suspects that your kidneys are not functioning properly, you may have to undergo a kidney function test (KFT). These are standard blood and urine tests that can detect renal issues. If you have other health conditions like diabetes or high blood pressure that may affect your kidneys, your doctor might suggest taking a kidney function test.

Your doctor will perform tests to evaluate your glomerular filtration rate (GFR) and assess the condition of your kidneys. Your GFR reveals how quickly your kidneys remove waste from your blood in one minute. GFR is calculated using a formula that takes into account age, body size, gender, and ethnicity. A GFR of more than 60 could be considered normal if there is no other sign of renal issues.

The other tests under KFT may include the following.

• Urinalysis: A urinalysis analyses the presence of blood and protein in your urine. Your doctor might need a 24-hour urine collection sample. This may help doctors determine how quickly a waste product called creatinine is getting cleared from your body.

• Serum creatinine test: This blood test determines whether there are high levels of creatinine in your blood. The function of the kidneys is to filter out the creatinine from the blood completely. Hence, a high creatinine level indicates a renal issue.

• Blood urea nitrogen (BUN): The blood urea nitrogen (BUN) test examines the levels of nitrogen in the blood. The breakdown of proteins produces urea nitrogen in the blood.

Stages of kidney disease

Below are the five stages of chronic kidney disease.

• Stage 1: It indicates a normal functioning kidney with a GFR of more than 90 mL/min

• Stage 2: Indicates mildly reduced kidney function with a GFR of 60–89 mL/min

• Stage 3A: Shows GFR of 45–59 mL/min

• Stage 3B: Indicates GFR of 30–44 mL/min

• Stage 4: Shows severe decrease in kidney function with a GFR of 15–29 mL/min

• Stage 5: Indicates kidney failure with a GFR of less than15mL/min

What are the various types of kidney disease?

There are five common kidney diseases. Here’s a list. 

1. Chronic kidney disease (CKD)

It is the most common type of kidney disease. Chronic kidney disease is a prolonged condition caused by high blood pressure. 

2. Kidney Stones

When minerals and other chemicals in the blood get deposited in the kidneys, they form solid lumps (stones). Kidney stones often come out of the body through urination but are extremely painful to pass.

3. Glomerulonephritis

It is caused due to the inflammation of the glomeruli. Glomeruli are exceptionally minute structures that filter blood inside the kidneys. Glomerulonephritis can be caused by infections or medicinal side effects.

4. Polycystic kidney disease

This causes the kidneys to develop multiple cysts or small sacs of fluid inside them. These cysts can impair kidney function and may lead to failure of the kidneys.

5. Urinary tract infections

This occurs when microorganisms enter the urinary tract and cause infection. Bacteria are the most prevalent cause of UTIs, while fungi can infect the urinary system in rare cases. Most UTIs are caused by E. coli bacteria that reside in the gut.

Treatment of kidney disease

The treatment of kidney disorders is determined by the origin and severity of the problem. It typically involves addressing the disease's underlying cause. To treat kidney problems, your doctor might use one or more of the following procedures.

1. Medication

You may be prescribed blood pressure drugs by your doctor to help decrease the progression of renal disease. Even if you do not have high blood pressure, you may be administered these drugs to help maintain kidney function.

Your doctor may also treat you with cholesterol-lowering medications. These drugs can help lower blood cholesterol levels and keep the kidneys healthy. Based on your symptoms, your doctor may also recommend medications to address edema and anaemia.

2. Diet and lifestyle changes

Implementing dietary modifications is as important as taking medicine. Following a healthy lifestyle can help minimise the risk of kidney disease. These factors include the following.

• Taking insulin to manage diabetes

• Nutritious diet

• Exercise regularly and stay physically active

• Manage your weight

• Avoid fatty foods

• Cut down on your salt intake

• Eat low-fat dairy products

• Limit alcohol usage

• Quit smoking

3. Dialysis

Dialysis is an artificial method of purifying blood. It serves its purpose when the kidneys fail to function. People with advanced renal disease must undergo dialysis.

Dialysis is classified into two categories.

• Haemodialysis: In this process, blood is pushed through a special machine that filters out waste materials and fluid.

• Peritoneal dialysis: This process includes a cleansing fluid called dialysate, which is injected through a catheter tube into the peritoneal cavity of the abdomen. Dialysate accumulates waste materials from blood vessels in the peritoneum, which is the lining of the abdomen. After that, the dialysate is emptied from the body.

4. Kidney transplant

If you have a final-stage renal disease (ESRD), in which both of your kidneys fail to function, you may require a kidney transplant. This is a condition related to permanent kidney failure.  During a kidney transplant, a healthy kidney from a donor is used to replace a failed kidney through surgery. The kidney could come from either a deceased organ donor or a living donor.

Frequently Asked Questions

Here are some frequently asked questions about Nephrology.

How can kidney disease be prevented?

Kidney disease can be prevented by taking the following measures.

• Drink enough water

• If you have diabetes, keep a check on your blood sugar levels

• Manage your blood pressure

• Cut down your salt intake

• Quit smoking

• Be careful while taking OTC medications

What is the simple meaning of Nephrology?

Nephrology deals with the study of the kidneys and related disorders that affect their functions. 

What are the three signs of kidney disease?

Bloody and frothy urine, changes in urination, and ankle and foot edema can be the three warning signs of kidney disease.

Sources:

• https://www.niddk.nih.gov/health-information/kidney-disease/kidneys-how-they-work#:~:text=Each%20of%20your%20 kidneys%20 is,your%20blood%20and%20removes%20wastes.

• https://www.ncbi.nlm.nih.gov/books/NBK535404/#:~:text=Some%20common%20symptoms%20and%20signs,Loss%20of%20appetite

• https://www.niddk.nih.gov/health-information/kidney-disease/chronic-kidney-disease-ckd/tests-diagnosis

• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089693/

• https://www.niddk.nih.gov/health-information/professionals/advanced-search/explain-kidney-test-results#:~:text=A%20blood%20test%20and%20a,glomerular%20filtration%20rate%20(GFR).

• https://www.nichd.nih.gov/health/topics/urinary/conditioninfo/causes#:~:text=A%20UTI%20develops%20when%20microbes,the%20bowel%2C%20cause%20most%20UTIs.

• https://www.niddk.nih.gov/health-information/kidney-disease/kidney-failure/choosing-treatment

• https://www.niddk.nih.gov/health-information/kidney-disease/kidney-failure/peritoneal-dialysis

• https://www.niddk.nih.gov/health-information/kidney-disease/kidney-failure/kidney-transplant

Disclaimer: The content on this page is generic and shared only for informational and explanatory purposes. Please consult a doctor before making any health-related decisions.