Alport syndrome is an inherited (usually X-linked) disorder involving damage to the kidney, blood in the urine , and in some families, loss of hearing . The disorder may also include eye defects .

Alternative Names

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

Causes, incidence, and risk factors

Alport syndrome is very similar to hereditary nephritis. There may be nerve deafness and congenital eye abnormalities associated with Alport syndrome. The cause is a mutation in a gene for collagen. The disorder is uncommon, and most often affects males since the genetic defect is typically found on the X chromosome. In women, the disorder is usually mild, with minimal or no symptoms. Women can transmit the gene for the disorder to their children, even if the woman has no symptoms of the disorder. In men, the symptoms are more severe and progress faster. The disorder causes chronic glomerulonephritis with destruction of the glomeruli. Initially, there are no symptoms. Progressive destruction of the glomeruli causes blood in the urine and decreases the effectiveness of the kidney's filtering system. There is progressive loss of kidney function and accumulation of fluids and wastes in the body, with eventual progression to end-stage renal (kidney) disease at an early age. ESRD , caused by Alport syndrome, often develops between adolescence and age 40. Risk factors include having a family history of Alport syndrome, nephritis, end-stage renal disease in male relatives, hearing loss before age 30, bloody urine , glomerulonephritis , and similar disorders.

Signs and tests

Examination is nonspecific, except for blood in the urine . Minute amounts of blood (microscopic hematuria ) is present from birth in nearly all affected males. The blood pressure may be elevated. Examination of the eyes may show fundus (posterior inner part of eye) or lens changes, cataracts , or lens protrusion (lenticonus). Examination of the ears shows no structural changes.

Treatment

Treatment goals include monitoring and controlling progression of the disease and treatment of symptoms. The most important task is strict control of high blood pressure . Treatment of chronic renal failure will become necessary. This may include dietary modifications, fluid restriction, and other treatments. Ultimately, chronic renal failure progresses to end-stage renal disease , requiring dialysis or transplantation. Surgical repair of cataracts ( cataract extraction ), or repair of the anterior lenticonus is possible. Loss of hearing is likely to be permanent. Counseling and education to increase coping skills, and learning new skills such as lipreading or sign language may be of some benefit. Hearing aids are helpful. Young men with Alport syndrome should use hearing protection in noisy environments. Genetic counseling may be recommended because of the inherited pattern of the disorder.

Expectations (prognosis)

In women, there is usually a normal life span with no manifestation except for blood in the urine . Rarely, women exhibit hypertension , edema , and nerve deafness as a complication of pregnancy . In men, deafness , visual difficulties, and renal failure are likely by age 50.

Complications

Calling your health care provider

Call for an appointment with your health care provider if symptoms indicating Alport syndrome may be present, or if there is a history of Alport syndrome and children are planned. Call your health care provider if urine output decreases or stops. (This may be a symptom of chronic renal failure .)

Prevention

This uncommon disorder is inherited. Awareness of risk factors, such as a family history of the disorder, may allow the condition to be detected early.