This is a health condition in which kidneys are affected. The primary cause of Alport syndrome is a mutation in the collagen genes. Protein and blood in the urine, hearing and vision problems, and kidney failure are the most common symptoms of this condition. Fortunately, several treatment methods are available to lessen the symptoms and improve overall health. Physicians usually prescribe ACE inhibitors and ARBs.
What is Alport Syndrome?
A genetic disease in which the kidneys do not create enough type IV collagen proteins. These proteins consist of 3 collagen chains called alpha chains that are twisted together like a rope. If this condition occurs, an individual may experience quite severe adverse reactions. However, if the body creates all chains but one is not produced correctly, the chains cannot combine and function. In such cases, certain mild symptoms can happen.
This IV collagen protein is very important in maintaining the filtration membrane in the kidneys (also called glomerular basement membranes or GBM). This membrane consists of a three-layer structure that is responsible for blood filtration. In addition, blood filtration helps the body get rid of toxins. GBM also helps to maintain blood cells and proteins in the blood and not go into the urine. If this membrane does not work correctly, proteins and blood cells may enter into urine (pee). As a result, a person will experience reduced kidney function over time.
IV collagen protein also can be found in the ears and eyes. That’s why people with this condition can experience vision or hearing problems.
Inherited Alport Syndrome
This disease has 3 genetic types. For example:
X-linked Alport Syndrome (XLAS)
In such cases, the condition is linked to the X chromosome. This one of two human chromosomes (X and Y) and the location where is created alpha 5 chain (COL3A5).
Men and people assigned to male at birth (AMAB) are more likely to experience severe symptoms because they have only one X chromosome. Females or people assigned to female at birth (AFAB) have two X chromosomes, which makes them experience mild symptoms. It occurs because a female can have one normal X chromosome and one abnormal.
However, males pass to their male child’s Y chromosome, which means that they cannot pass XLAS to the children. In all other cases, men pass the X chromosome to female children. In such cases, a female child can have XLAS.
Approximately, 60%-80% of all Alprost syndrome cases are XLAS.
Autosomal Recessive Alprost Syndrome (ARAS)
In such cases, the abnormal genes can pass to children if both parents have ARAS. There is a 50% chance that your biological children will have abnormal genes. However, it is not necessarily that they will have Alport syndrome. Roughly 15% of all Alport syndrome cases are ARAS. In addition, the ARAS does not depend on the child’s assigned sex.
Autosomal Dominant Alport Syndrome (ADAS)
ADAS like ARAS does not depend on a person’s assigned sex, which means the inheritance and severity are the same in all children. In case you have ADAS, there is a 50% chance that the abnormal gene will pass to your biological child. About 25%-35% of all Alport syndrome cases are ADAS.
Who Does Impact Alport Syndrome?
This health condition can affect anyone because it is an inherited disease. Therefore, whether one or both parents pass it to their children. In some circumstances, Alport syndrome can develop even if the parents do not have the mutated gene. Such cases account for roughly 15% of Alport syndrome cases.
Symptoms
This condition causes the glomerular basement membrane to not filter blood properly, which leads to a leakage of blood and proteins in the urine. Thus, the cells become inflamed and irritated. In addition, podocytes are certain cells that create GBMs. In case the surrounding cells are inflamed, podocytes try to increase IV collagen into the GBMs. Once this occurs, the membrane becomes thicker.
When the GBMs become thicker, it may lead to scar tissue (fibrosis) and some health problems (such as chronic kidney disease or even kidney failure).
Check below the most common clinical symptoms of this condition:
- Proteinuria (protein in the urine)
- Microscopic hematuria (bloody urine)
- Chronic kidney disease
- Kidney failure
- Hearing loss
- Vision problems
Usually, the first Alport syndrome symptom is microscopic hematuria. It means you have small blood cells in the urine that you cannot see with the naked eye. These blood cells are observed under a microscope only.
In addition, once kidney function begins to decrease, you may experience chronic kidney disease (CKD). Unfortunately, people with CKD usually do not have any symptoms until kidney failure. Check below some kidney failure symptoms:
- Swelling (edema around the hands, ankles, and other body parts)
- Fatigue (extreme tiredness)
- Nausea
- Vomiting
- Muscle cramps
Another common Alport Syndrome symptom is hearing loss but it mostly occurs in people with ARAS and men with XLAS. In any case, anyone with this health condition can experience hearing loss. It commonly decreases gradually and people realize it in severe cases.
Additionally, due to this genetic disease, people may also develop certain eye disorders. For example corneal abrasion. This condition provokes your eyes to hurt but not every time causes vision loss. In other cases, people with Alport syndrome can develop cataracts.
If you experience any of the previous symptoms or any others, it is recommended to visit a doctor at once.
Is Alport Syndrome Contagious?
Fortunately, this condition is not contagious, which means it cannot pass from one person to another. The only way this genetic disorder can pass to someone is heritable (from biological parents to biological children).
Diagnosis
Doctors will ask you some questions about your symptoms and medical and family history. Furthermore, to confirm this genetic disease they should perform certain tests. For example:
- Urinalysis (a urine test to check for the visual, chemical, and microscopic aspects of the pee)
- Creatinine clearance test or cystatin C blood tests (these tests are done to verify how well your kidneys filter the blood)
- Estimated glomerular filtration rate or eGFR (this test helps to understand how well the kidneys clean the blood)
- Kidney biopsy (during this procedure, your doctor will remove a small sample of your kidney and send it to the laboratory)
- Genetic tests (these tests help to identify the mutations in the collagen genes)
- Hearing test (some physicians may order you to do an audiogram)
- Eye examination – During this examination, physicians verify your vision and the surface of the eye. Healthcare providers may also perform an optical coherence tomography (OCT) imaging test.
Treatment
However, there is no cure for Alprost syndrome but with proper treatment, you can reduce the symptoms and improve overall health. The treatments involve a decrease in kidney decline and help to delay kidney failure. Check below some treatment options:
- Angiotensin-converting Enzyme (ACE) Inhibitors – These medications usually decrease the blood pressure and protein in the urine and protect your kidneys.
- Angiotensin II Receptor Blockers (ARBs) – These medicines are very similar to ACE inhibitors, which means they have the same benefits.
- Sodium-glucose Transported Type 2 (SGLT-2) Inhibitors – Physicians prescribe these medicines to reduce the risk of kidney failure in people with CKD or Alprost syndrome. In most cases, there is a combination of medicines including ACE inhibitors or ARBs with SGLT-2 inhibitors.
- Sodium-controlled Diet – It is advised to decrease the amount of salt and sodium in your diet because it can help to reduce blood pressure and keep your heart and kidneys healthy.
Frequently Asked Questions
Is it possible to prevent Alprost syndrome?
This genetic condition cannot be prevented but you can check your family history, which will help to prevent it from passing to your biological child. Early diagnosis and treatment is the best method to delay kidney failure. Consult with your doctor for more details.
Can a kidney transplant cure Alport syndrome?
A new kidney with normal IV collagen type and filtering membranes can help to cure this genetic disorder. However, the new kidney cannot help with other Alprost syndrome symptoms. For example hearing or vision loss.
How common is Alport syndrome?
This genetic disorder is considered rare. According to some researchers, approximately 200,000 people have Alport syndrome in the United States. However, experts continue to find people with mild forms of Alprost syndrome. It means that this condition can be more common than current data.
