Pediatric Alport syndrome

What is pediatric Alport syndrome?

Alport syndrome is a rare, genetic disorder that damages the tiny blood vessels called glomeruli in a child’s kidneys. When glomeruli are damaged, they are unable to filter waste and remove extra fluid from the body as needed. This causes a gradual loss of kidney function and can lead to kidney disease, kidney failure and eventually, end-stage renal disease (ESRD).

The genes affected by Alport syndrome control a protein called collagen. Collagen plays an important role in normal kidney function and affects the eyes and ears. Therefore, children with Alport syndrome may also suffer from abnormalities in their eyes and ears that can lead to vision and hearing loss. 

Alport syndrome was first described by Dr. Cecil Alport who published a paper in 1927 describing the syndrome.

What are the different types of pediatric Alport syndrome?

There are three genetic types of Alport syndrome:

1. X-linked Alport syndrome (XLAS) -  the most common type of Alport syndrome, caused by mutations in the COL4A5 gene located on the X chromosome.

2. Autosomal recessive Alport syndrome (ARAS) - this happens when a child receives a copy of a defective gene from both parents.

3. Autosomal dominant Alport syndrome (ADAS) - the least common type of Alport syndrome, caused by mutations to the COL4A3 or COL4A4 genes.

What are the signs and symptoms of pediatric Alport syndrome?

Symptoms of Alport syndrome depend on the specific gene mutation. All children with Alport syndrome will have symptoms that affect the kidneys. The first and most common symptom of Alport symptoms is usually hematuria (blood in the urine).

Risk factors

Male children with Alport syndrome are more likely than females to have problems with hearing and vision.

Other symptoms may include:

• Edema (swelling in the ankles, legs and face)

• Hypertension (high blood pressure)

• Loss of kidney function

• Progressive hearing loss

• Proteinuria (protein in the urine)

• Vision problems that affect the cornea, lens and retina

Rarely, chest and abdominal aneurysms may occur in males with Alport syndrome.

What are the causes of pediatric Alport syndrome?

Alport syndrome is caused by mutations (changes) to specific genes before a child is born.