IgA nephropathy usually doesn't cause symptoms in the early stages.

The disease can go unnoticed for decades and is sometimes first suspected when routine tests reveal protein and red blood cells in your urine that can't be seen without a microscope (microscopic hematuria).

Signs and symptoms of IgA nephropathy when kidney function is impaired include:

Cola- or tea-colored urine (caused by red blood cells in the urine)

Repeated episodes of cola- or tea-colored urine, sometimes even visible blood in your urine, usually during or after an upper respiratory or other type of infection

Pain in the side(s) of your back below your ribs (flank)

Foam in the toilet water from protein in your urine

Swelling (edema) in your hands and feet

High blood pressure

When to see a doctor

Make an appointment with your doctor if you notice blood in your urine.

Urinary bleeding may be caused by strenuous exercise, some foods, medications or a urinary tract infection.

But prolonged or repeated bleeding may indicate a serious medical problem and should always be evaluated.

Also see your doctor if your urine is foamy or if you develop sudden swelling in your hands and feet.