Alport syndrome Health Article

Definition

Alport syndrome is an inherited disorder that leads to kidney damage.

Alternative Names

Hereditary nephritis; Hematuria - nephropathy - deafness; Hemorrhagic familial nephritis; Hereditary deafness and nephropathy

Causes, incidence, and risk factors

Alport syndrome is an inherited form of kidney inflammation (nephritis). It's caused by a mutation in a gene for a protein in connective tissue, called collagen.

The disorder is uncommon, and most often affects males. Women can transmit the gene for the disorder to their children, even if they have no symptoms.

Risk factors include:

• End-stage kidney disease in male relatives
• Family history of Alport syndrome
• Glomerulonephritis
• Hearing loss before age 30
• Nephritis

Symptoms

The disorder damages the tiny blood vessels in the kidneys, called glomeruli, that filter wastes.

At first, there are no symptoms. Then the progressive destruction of the glomeruli leads to blood in the urine and decreases the effectiveness of the kidney's filtering system. There is a progressive loss of kidney function and a build-up of fluids and wastes in the body.

In women, the disorder is usually mild, with minimal or no symptoms. In men, the symptoms are more severe and get worse faster.

Symptoms include:

• Abnormal urine color
• Ankle, feet, and leg swelling
• Blood in the urine
• Cough
• Decrease or loss of vision, more common in males
• Loss of hearing, more common in males
• Swelling around the eyes
• Swelling, overall

The condition can progress to end-stage renal disease (ESRD) at an early age (between adolescence and age 40).

Note: There may be no symptoms in some cases. Symptoms of chronic kidney failure or heart failure may be present or may develop.

Signs and tests

• Changes to the eye, including the fundus (posterior inner part of eye), lens, cataracts, or lens protrusion (lenticonus)
• Elevated blood pressure
• Tiny amounts of blood in the urine (microscopic hematuria)

The following tests may be done:

• Urinalysis shows blood, protein, and other abnormalities.
• BUN and creatinine are elevated.
• Red blood cell count, hematocrit may decrease.
• Hematuria test is positive.
• Audiometry may show nerve deafness.
• Renal biopsy shows chronic glomerulonephritis with changes typical of Alport syndrome.