Acute nephritic syndrome

Glomerulonephritis - acute; Acute glomerulonephritis; Nephritis syndrome - acute

Acute nephritic syndrome is often caused by an immune response triggered by an infection or other disease.

Common causes in children and adolescents include:

• Hemolytic uremic syndrome
• Henoch-Schönlein purpura
• IgA nephropathy
• Post-streptococcal glomerulonephritis

Common causes in adults include:

• Abdominal abscesses
• Goodpasture syndrome
• Hepatitis B or C
• Infective endocarditis
• Membranoproliferative GN I
• Membranoproliferative GN II
• Rapidly progressive (crescentic) glomerulonephritis
• SLE or lupus nephritis
• Vasculitis
• Viral diseases such as mononucleosis, measles, mumps

The inflammation affects the function of the glomerulus. This is the part of the kidney that filters blood to make urine and remove waste. As a result, blood and protein appear in the urine, and excess fluid builds up in the body.

Swelling of the body occurs when the blood loses a protein called albumin. Albumin keeps fluid in the blood vessels. When it is lost, fluid collects in the body tissues.

Blood loss from the damaged kidney structures leads to blood in the urine.

Common symptoms of nephritic syndrome are:

• Blood in the urine (urine appears dark, tea-colored, or cloudy)
• Decreased urine output (little or no urine may be produced)
• Swelling of the face, eye socket, legs, arms, hands, feet, abdomen, or other areas
• High blood pressure

Other symptoms that may occur include:

• Blurred vision, usually from burst blood vessels in the retina of the eye
• Cough containing mucus or pink, frothy material from fluid buildup in the lungs
• Shortness of breath, from fluid buildup in the lungs
• General ill feeling (malaise), drowsiness, confusion, aches and pains, headache

Symptoms of acute kidney failure or chronic kidney disease may develop.

During an examination, your health care provider may find the following signs:

• High blood pressure
• Abnormal heart and lung sounds
• Signs of excess fluid (edema) such as swelling in the legs, arms, face, and belly
• Enlarged liver
• Enlarged veins in the neck

Tests that may be done include:

• Blood electrolytes
• Blood urea nitrogen (BUN)
• Creatinine - blood
• Creatinine clearance
• Potassium test
• Protein in the urine
• Urinalysis
• Urine appearance and color

A kidney biopsy will show inflammation of the glomeruli, which may indicate the cause of the condition.

Tests to find the cause of acute nephritic syndrome may include:

• ANA titer (lupus)
• Antiglomerular basement membrane antibody
• Antineutrophil cytoplasmic antibody for vasculitis (ANCA)
• Blood culture
• Culture of the throat or skin
• Serum complement (C3 and C4)

The goal of treatment is to reduce inflammation in the kidney and control high blood pressure. You may need to stay in a hospital to be diagnosed and treated.

Your provider may recommend:

• Bedrest until you feel better with treatment
• A diet that limits salt, fluids, and potassium
• Medicines to control high blood pressure, reduce inflammation, or to remove fluid from your body
• Kidney dialysis, if needed

You can often ease the stress of illness by joining support groups where members share common experiences and problems.

The outlook depends on the disease that is causing the nephritis. When the condition improves, symptoms of fluid retention (such as swelling and cough) and high blood pressure may go away in 1 or 2 weeks. Urine tests may take months to return to normal.

Children tend to do better than adults and usually recover completely. Only rarely do they develop complications or progress to chronic glomerulonephritis and chronic kidney disease.

Adults do not recover as well or as quickly as children. Although it is unusual for the disease to return, in some adults, the disease does return and they will develop end-stage kidney disease and may need dialysis or a kidney transplant.

Call your provider if you have symptoms of acute nephritic syndrome.

Often, the disorder cannot be prevented, although treatment of illness and infection may help to reduce the risk.