Nephrotic Syndrome: What It Is, Causes, Symptoms, Treatment & Types

What Is Nephrotic Syndrome?

Nephrotic syndrome causes a cluster of symptoms that appear when the kidneys' filtering units, called glomeruli, become damaged and start leaking protein into the urine.

Healthy glomeruli hold protein back. When they fail, albumin spills through, and albumin levels in the blood fall. Fluid that was being held in the bloodstream shifts out into the body's tissues, causing swelling. The liver, responding to low protein, increases lipid production, which often results in high cholesterol in these patients.

What Are the Types of Nephrotic Syndrome?

The condition splits into primary forms and secondary forms. Within those two categories, the main subtypes include:

How Does Nephrotic Syndrome Progress?

Nephrotic syndrome does not follow a fixed staging system like some chronic diseases. Instead, it progresses through different clinical phases depending on the extent of kidney damage, the response to treatment, and whether the condition relapses. The phases of nephrotic syndrome are described below:

How Common is Nephrotic Syndrome in India?

India has 2.9 children per 100,000 paediatric cases of nephrotic syndrome. Applied to India's population size, that's a substantial absolute number of paediatric patients, many in the early years of school.

The overall disease burden in India is considered to be rising, driven by increasing rates of diabetes and related kidney complications among the adult population.

What Are the Symptoms of Nephrotic Syndrome?

The symptoms of nephrotic syndrome usually develop as protein loss through urine increases. While some people first notice mild swelling or foamy urine, others may develop more severe symptoms as the disease progresses. The early warning signs and advanced symptoms include:

Diseases Similar to Nephrotic Syndrome

Kidney disorders can often cause swelling, changes in urination, and reduced kidney function, making them easy to confuse. However, they differ in their underlying causes, symptoms, treatment approach, and long-term outlook. The table below highlights the key differences among three kidney conditions, including nephrotic syndrome, for better understanding:

Nephrotic Syndrome Vs. Nephritic Syndrome Vs. Chronic Kidney Disease

What Causes Nephrotic Syndrome?

The primary cause of nephrotic syndrome is glomerular injury. But what caused the injury determines the course of action.

• Idiopathic Causes: MCD, or minimal change disease, is the reason for most cases amongst children. However, some causes may include certain medications, viral infections, or an allergic reaction to certain triggers.

• Poorly Controlled Diabetes: Among adults, a major cause of secondary nephrotic syndrome is believed to be uncontrolled levels of diabetes.

• Membranous Nephropathy: Thickening of the glomerular membrane, commonly seen in adults.

• Autoimmune Conditions: Commonly seen in females of reproductive age, lupus nephritis is one of the leading autoimmune conditions that may lead to nephrotic syndrome.

• Chronic Viral Infections: Long-term viral infections like HIV, Hep B, and Hep C may cause significant glomerular damage over time.

• Infections: Hepatitis B, hepatitis C, HIV, and certain other infections may affect the kidneys.

• Certain Medicines: Long-term use of some medicines, including NSAIDs, can increase the risk.

• Inherited or Genetic Disorders: Rare genetic conditions can affect kidney function and cause nephrotic syndrome.

• Focal Segmental Glomerulosclerosis (FSGS): Scarring of parts of the kidney's filtering units.

What Are the Complications of Nephrotic Syndrome?

Nephrotic syndrome can lead to serious health complications if untreated:

• Infections: Patients with nephrotic syndrome already have reduced immune defenses, which can increase the chances of getting other infections.

• Blood Clots: Loss of clotting factor proteins (coagulation disorders) keeps such an individual at high risk of blood clot formation. Common complications include deep vein thrombosis (DVT), renal vein thrombosis (RVT), and pulmonary embolism.

• Cardiovascular Disease: High cholesterol levels are one of the most common symptoms in nephrotic syndrome patients. High cholesterol levels can lead to endothelial dysfunction, hypertension, and the risk of atherosclerosis.

• Malnutrition: Continued loss of protein via urine, coupled with a loss of appetite, can lead to malnutrition.

• Severe Oedema: Persistent fluid retention can cause swelling in the legs, abdomen, and around the eyes.

• Chronic Kidney Disease: Persistent kidney damage may gradually reduce kidney function.

• Acute Kidney Injury: A sudden decline in kidney function can occur in some cases.

When Should I See My Healthcare Provider?

Seek medical attention if you notice symptoms suggestive of nephrotic syndrome.

• When you see facial puffiness every day, around the time of waking up.

• Unusually foamy urine, where the foam doesn’t clear up in seconds.

• Swelling of the limbs and torso, coupled with inexplicable tiredness.

• Sudden onset of fever, loss of appetite, and appearance of weight gain.

• Shortness of breath even in the absence of strenuous exercise or swollen and painful limbs.

How Is Nephrotic Syndrome Diagnosed?

Doctors may recommend the following tests to diagnose nephrotic syndrome:

Overview Table

How Is Nephrotic Syndrome Treated?

Two things happen at the same time: managing symptoms and going after the underlying cause.

Common Medicines Used to Treat Nephrotic Syndrome

Commonly prescribed medicines to treat nephrotic syndrome include:

• Prednisolone (Corticosteroid): It suppresses the abnormal immune response, reduces inflammation in the glomeruli, and helps decrease protein leakage into the urine.

• ACE Inhibitors and ARBs (Enalapril, Ramipril, Losartan): These medicines lower blood pressure and reduce the amount of protein lost in the urine, helping protect kidney function over the long term.

• Diuretics (Furosemide, Torsemide): Commonly known as water tablets, these medicines help remove excess fluid from the body and relieve swelling in the legs, face, and abdomen.

• Statins (Atorvastatin, Rosuvastatin): High cholesterol is common in nephrotic syndrome. Statins help reduce cholesterol levels and lower the long-term risk of cardiovascular disease.

• Immunosuppressive Medicines (Tacrolimus, Cyclosporine, Cyclophosphamide, Mycophenolate Mofetil, Rituximab): These medicines are used in patients with steroid-resistant, steroid-dependent, or frequently relapsing nephrotic syndrome. They help control the immune system and reduce further kidney damage.

• Warfarin or Enoxaparin: Blood thinners may be recommended for patients at high risk of developing blood clots.

Note: The choice of medicine depends on the patient's age, the underlying kidney disease, and the severity of nephrotic syndrome. Treatment should always be guided by a nephrologist.

Living with Nephrotic Syndrome in India: Challenges and Caregiving

Treatment of nephrotic syndrome often includes long-term medical care, periodic checkups, and regular monitoring. Some of the major challenges and essential care points for nephrotic syndrome patients include the following:

What Is the Prognosis for Nephrotic Syndrome?

Minimal change disease (MCD), which causes nephrotic syndrome, generally has a favourable prognosis in children. Around 80% respond to initial treatments. Relapses may happen, sometimes frequently, and some children continue to relapse through adolescence, but the majority outgrow the condition without long-term kidney damage.

The concern lies with children who are steroid-resistant from the start, as such resistance usually indicates an underlying pathology other than MCD.

Secondary forms, kidney health largely depends on how well the underlying disease is controlled, whether that's blood sugar, a viral infection, or an autoimmune condition.

Can Nephrotic Syndrome Be Prevented?

The following measures may help reduce the risk of nephrotic syndrome:

• Control Diabetes and Blood Pressure: Blood sugar and blood pressure control are the most important steps an adult can take to reduce the risk of diabetic nephropathy, the leading secondary cause of nephrotic syndrome globally.

• Treat Viral Infections Early: Early treatment of hepatitis B and C may help prevent significant glomerular damage.

• Reduce Nephrotoxic Medications: Nonsteroidal anti-inflammatory drugs (NSAIDs) are harmful due to their toxic effects on the nephron and kidneys in general. Unprescribed and uncontrolled usage of over-the-counter NSAIDs should be avoided.

• Follow Up Regularly: A health checkup once or twice a year is the best way to keep your body in check before a disease fully matures.

Nephrotic Syndrome Treatment Cost in India

The cost of treating nephrotic syndrome in India varies depending on the underlying kidney illness, intensity of symptoms, tests necessary, response to treatment, and development of consequences such as renal failure. The approximate cost range are listed below:

Note: The treatment costs mentioned above are approximate estimates and may vary depending on the hospital, city, treating specialist, disease severity, investigations required, and the patient's overall health. Patients should consult their healthcare provider or hospital for an accurate treatment estimate.

Does Health Insurance Cover Nephrotic Syndrome?

Nephrotic syndrome involves multiple hospitalisations, specialist consultations, diagnostic tests, and long-term medication. These are usually covered under standard health insurance plans in India. Coverage typically includes inpatient hospitalisation, nephrology consultations, biopsy procedures, and prescribed medications. Coverage may vary depending on the plan and the insurer.

It is advisable to review individual policy terms carefully before purchasing health insurance to understand policy coverage inclusions and exclusions.

How Much Health Insurance Coverage Is Needed for Nephrotic Syndrome?

As with any disease, the insurance coverage needed depends on the treatment approach, severity of the disease, and location. Overall, a minimum coverage of ₹25 lakh is a fair starting point, especially when long-term kidney care risks are considered.

However, it is important to remember that nephrotic syndrome has a risk of relapse, so higher coverage may be wise. Patients at a higher risk of relapse may include people with compromised immune systems and CKD (chronic kidney disease).

Dialysis can cost approximately ₹3-₹8 lakh per year. Kidney transplant procedures may cost around ₹8-₹20 lakh, excluding post-operative care and lifelong medication. Therefore, higher coverage up to ₹1 crore for health insurance would be beneficial in such situations.