Minimal change disease

Other Names: Idiopathic minimal change nephrotic syndrome; Minimal change nephrotic syndrome; Minimal change glomerulopathy; MCNS

Minimal change disease is a kidney disease in which there is damage to the filtering units of the kidney (glomeruli). It is the most common cause of nephrotic syndrome in children. Nephrotic syndrome is a group of symptoms that include protein in the urine, low blood protein levels in the blood, high cholesterol levels, high triglyceride levels, and swelling.

Cause

Each kidney is made of more than a million units called nephrons, which filter blood and produce urine. In minimal change disease, there is damage to the glomeruli. These are the tiny blood vessels inside the nephron where blood is filtered to make urine and waste is removed. The disease gets its name because this damage is not visible under a regular microscope. It can only be seen under a very powerful microscope called an electron microscope. Minimal change disease is the most common cause of nephrotic syndrome in children. It is also seen in adults with nephrotic syndrome, but is less common.

The cause is unknown, but the disease may occur after or be related to:

• Allergic reactions
• Use of NSAIDs
• Tumors
• Vaccinations (flu and pneumococcal, though rare)
• Viral infections

Signs and symptoms

There may be symptoms of nephrotic syndrome, including:

• Foamy appearance of the urine
• Poor appetite
• Swelling (especially around the eyes, feet, and ankles, and in the abdomen)
• Weight gain (from fluid retention)
• Minimal change disease does not reduce the amount of urine produced. It rarely progresses to kidney failure.

Diagnosis

The health care provider may not be able to see any signs of the disease, other than swelling. Blood and urine tests reveal signs of nephrotic syndrome, including:

• High cholesterol
• High levels of protein in the urine
• Low levels of albumin in the blood
• A kidney biopsy and examination of the tissue with an electron microscope can show signs of minimal change disease.

Treatment

Corticosteroids are typically the first line of treatment for minimal change disease. The fluid retention and high blood pressure that often accompanies minimal change disease may be treated with the use of water pills (diuretics) in combination with a low sodium diet and blood pressure medications (such as angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blocker (ARB), calcium channel antagonists).

Other medications that may be used in instances of disease recurrence include those that are used to treat certain types of cancer (cyclophosphamide, chlorambucil, rituximab) and those that suppress the immune system (cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil).

There is an increased risk for the formation of blood clots (thromboembolic events) and infection in individuals with minimal change disease. It is recommended that individuals with minimal change disease stay active and should a blood clot occur, they may be treated with blood thinners. Infections, such as cellulitis, peritonitis, and pneumonia are common in individuals with minimal change disease and should be treated quickly.

Prognosis

In individuals who are not treated, there is an increased risk for infection and blood clotting events. About 5-10% of untreated adults may have spontaneous remission (resolution) of disease within a few months. One major indication of the long-term outcome of MCD is the initial response to corticosteroid treatment. About 80-95% of adults with MCD who receive treatment via corticosteroids experience complete remission of symptoms. About half of all adults treated for MCD have remission within four weeks, while 10-25% require longer treatment. MCD may recur or relapse in about half of all adults. This usually occurs within one year of treatment. Despite the potential for the disease to recur, the occurrence of kidney failure and end stage renal disease is rare.

NIH genetic and rare disease info

• NIH info on Minimal change disease

Minimal change disease is a rare disease.

Minimal change disease Resources
Latest articles Most recent articles Ongoing trials	Wikipedia