Hyperoxaluria And Oxalosis

High levels of oxalate in your urine are called hyperoxaluria. Oxalate is a substance your body naturally produces, and it's also found in some foods. Having too much oxalate in your urine can be a problem.

Hyperoxaluria can be caused by a genetic condition, problems with your intestines, or eating too many foods high in oxalate. Early diagnosis and treatment are crucial for healthy kidney function in the long run.

Oxalosis happens when the kidneys aren't working properly, as a result of hyperoxaluria. This leads to too much oxalate building up in your blood. The excess oxalate can then deposit in blood vessels, bones, and other organs, causing damage.

Hyperoxaluria often first shows up as a kidney stone. These stones can cause a variety of symptoms. You might experience:

• Sharp, intense pain: This pain can be felt in your back, side, lower abdomen, or groin.
• Colored urine: Your urine might appear pink, red, or brown because of blood in it.
• Frequent urination: You may feel the need to urinate more often than usual.
• Painful urination: Peeing itself can be painful.
• Difficulty urinating: You might have trouble urinating or only pass a small amount of urine.
• Other symptoms: Other possible symptoms include chills, fever, nausea, or vomiting.

These symptoms can be caused by other conditions, so it's important to see a doctor if you experience them.

Kidney stones aren't very common in kids. When they do occur in children and teens, it's often because of a health issue, like a condition called hyperoxaluria. This means there's too much oxalate in the body, which can lead to kidney stones.

Any child or teenager with a kidney stone should see a doctor for a checkup. Part of this checkup should involve testing how much oxalate is in their urine. Adults who have repeated kidney stones should also get tested for high oxalate levels in their urine. This helps doctors figure out the cause and recommend the best treatment.

Hyperoxaluria: Too Much Oxalate in Your Urine

Hyperoxaluria is a condition where your body builds up too much oxalate, a chemical substance, in your urine. This can lead to various health problems, especially kidney issues. There are three main types:

1. Primary Hyperoxaluria:

This is a rare, inherited condition passed down through families. It happens because of a change in a specific gene. Normally, the liver produces a protein that keeps oxalate levels in check. In primary hyperoxaluria, either the liver doesn't make enough of this protein, or the protein doesn't work correctly. The body then tries to get rid of the extra oxalate through the kidneys, which filter waste from the blood. However, too much oxalate can combine with calcium to form hard deposits called kidney stones and crystals. These can damage the kidneys and eventually lead to kidney failure.

Kidney stones often appear early in life, usually causing problems in childhood and adolescence. Many people with primary hyperoxaluria develop kidney problems in their young adult years, and some even experience kidney failure in infancy. Thankfully, not everyone with this condition will experience kidney failure.

2. Enteric Hyperoxaluria:

This type of hyperoxaluria happens when problems in the intestines cause the body to absorb more oxalate from the food you eat. This increased oxalate then ends up in your urine. Certain intestinal conditions, like Crohn's disease or short bowel syndrome (where parts of the small intestine have been removed), can contribute to enteric hyperoxaluria.

Sometimes, other health problems interfere with the small intestine's ability to absorb fats from food. Normally, oxalate in the gut combines with calcium and is eliminated in the stool. But, when there's more fat in the gut, calcium gets used up binding to the fat instead. This leaves the oxalate free to be absorbed into the bloodstream and filtered out by the kidneys. Procedures like Roux-en-Y gastric bypass surgery, which can alter fat absorption, also increase the risk of enteric hyperoxaluria.

3. Hyperoxaluria from a High-Oxalate Diet:

Eating a lot of foods high in oxalate can raise your risk of hyperoxaluria, or kidney stones, even if you don't have the other types. Foods like nuts, chocolate, tea, spinach, potatoes, beets, and rhubarb contain higher levels of oxalate. If you have diet-related or enteric hyperoxaluria, or have primary hyperoxaluria, your doctor might recommend limiting these foods to help manage your oxalate levels.

Primary hyperoxaluria can harm the kidneys if left untreated. Over time, the kidneys might stop working properly, a condition known as kidney failure. For some people, this is the first noticeable sign of the disease.

Kidney failure can cause several symptoms:

• Reduced or absent urination: You might urinate less often or not at all.
• Fatigue and illness: You may feel constantly tired and unwell.
• Loss of appetite: You might not feel hungry.
• Stomach upset and vomiting: You could experience nausea, vomiting, or both.
• Pale or discolored skin: Your skin might look paler than usual, or its color might change. This is sometimes linked to a low red blood cell count, also called anemia.
• Swelling in the hands and feet: Swelling, or edema, can occur in these areas.

Oxalosis develops when a person has primary or enteric hyperoxaluria and their kidneys aren't working effectively to remove extra oxalate. Without proper kidney function, oxalate builds up in the body. This buildup starts in the blood and then spreads to other parts, including the eyes, bones, skin, muscles, blood vessels, heart, and other organs.

In the later stages of oxalosis, the buildup of oxalate can cause serious problems outside the kidneys. These issues can include:

• Bone problems: Oxalate can damage bones.
• Anemia: The body might not produce enough red blood cells, leading to anemia.
• Skin sores or ulcers: Sores on the skin can develop.
• Heart and eye issues: Oxalate buildup can affect the heart and eyes.
• Growth and development problems in children: Children with oxalosis might experience problems with growth and development.

Diagnosing Hyperoxaluria: A Step-by-Step Guide

Hyperoxaluria is a condition where the body produces too much oxalate, a substance that can lead to kidney stones and other health problems. Doctors use a variety of tests to diagnose it and determine the extent of the condition.

Initial Evaluation:

Your doctor will likely start with a thorough physical examination. They'll also ask about your medical history, including any previous illnesses or surgeries, and your dietary habits. A detailed understanding of your diet is important because certain foods can increase oxalate levels in the body.

Diagnostic Tests:

Several tests can help determine if you have hyperoxaluria and the type.

• Urine Tests: You'll need to collect your urine for a full 24 hours in a special container. The lab will analyze this urine sample to measure oxalate levels and other relevant substances.

• Blood Tests: These tests assess kidney function and measure oxalate levels in your blood. This helps doctors understand how the kidneys are handling the excess oxalate.

• Stone Analysis: If you've had kidney stones, analyzing them can reveal if oxalate is the main component. This is done after the stone is passed or removed.

• Imaging Tests: X-rays, ultrasounds, and CT scans can identify kidney stones or calcium oxalate buildup in your body. These tests provide visual confirmation of potential issues.

More Detailed Tests (if needed):

If initial tests suggest hyperoxaluria, further investigations may be necessary to pinpoint the specific cause and its impact on your body.

• Genetic Testing (DNA): This test looks for gene changes that cause primary hyperoxaluria, a genetic form of the condition.

• Kidney Biopsy: This involves taking a small tissue sample from your kidney to examine for oxalate buildup.

• Echocardiogram: This imaging test checks for oxalate deposits in the heart.

• Eye Exam: Doctors may examine your eyes to look for oxalate deposits.

• Bone Marrow Biopsy: This test examines bone marrow for oxalate buildup.

• Liver Biopsy: In rare cases, a liver biopsy is done to check for enzyme deficiencies that can contribute to hyperoxaluria. This is usually only necessary if genetic testing doesn't provide a clear cause.

Family Considerations:

If you're diagnosed with primary hyperoxaluria, your family members, especially siblings, are at increased risk. They should also be screened for the condition. If you have a child with primary hyperoxaluria, genetic counseling can help you understand the risks and make informed decisions about future pregnancies, including genetic testing options. Genetic counselors experienced with hyperoxaluria can guide you through this process.

Hyperoxaluria Treatment: Managing Kidney Problems

Hyperoxaluria is a condition where your body produces too much oxalate, a substance that can form crystals in your kidneys. The treatment for hyperoxaluria depends on several factors, including the type of hyperoxaluria, the symptoms, how severe the condition is, and how well you respond to different treatments. Your healthcare team will work with you to find the best approach.

Medications

Several medications can help manage hyperoxaluria. A key medication for primary hyperoxaluria is lumasiran (Oxlumo). This medicine directly reduces the amount of oxalate in your body. Vitamin B6 (pyridoxine), in higher-than-normal doses, can also help reduce oxalate in the urine for some people with primary hyperoxaluria. Other medications, such as phosphates and citrates, are available to help prevent calcium oxalate crystals from forming. Your doctor might also prescribe thiazide diuretics depending on the other substances found in your urine. If you have enteric hyperoxaluria, taking calcium supplements with meals can help oxalate bind with calcium in your digestive system and be eliminated through your stool.

Lifestyle Changes

Drinking plenty of fluids is another important part of managing hyperoxaluria. If your kidneys are functioning well, increasing your water or other fluid intake helps flush out oxalate and prevent kidney stones.

Dietary changes are particularly important for people with enteric or diet-related hyperoxaluria. Your healthcare team may recommend restricting foods high in oxalate, such as certain fruits and vegetables (e.g., spinach, rhubarb, beets), nuts, and some types of chocolate. They might also advise you to limit salt and animal protein, and sugar intake. While dietary changes can help, they may not be effective for everyone with primary hyperoxaluria. Always follow the advice of your healthcare team.

Managing Kidney Stones

Kidney stones are a common problem for people with hyperoxaluria. Small stones often pass on their own. However, if a stone is large, painful, or blocks urine flow, it may need to be removed or broken down into smaller pieces to pass through your urinary tract.

Advanced Treatment Options

Over time, hyperoxaluria can damage your kidneys. If your kidneys are not functioning well enough, dialysis may be necessary. Dialysis filters waste from your blood, but it can't completely eliminate oxalate. A kidney transplant or, in some cases, a combined kidney and liver transplant, might be considered. A liver transplant is sometimes the only way to cure certain types of primary hyperoxaluria, as the liver plays a role in oxalate metabolism. The decision about which treatment is best for you will depend on the severity of your condition and your overall health.