What is Hyperoxaluria?
Hyperoxaluria is a condition in which you have too much oxalate in your urine. Oxalate in a natural chemical in your body, and it’s also found in certain types of food. But too much oxalate in your body can cause serious problems. High levels of oxalate are toxic because oxalate cannot be broken down by the body and accumulates in the kidneys that may cause kidney stones.
Hyperoxaluria can be caused by inherited disorders, an intestinal disease, weight loss surgery, or eating too much oxalate-rich foods. The long term health of your kidneys depends on early diagnosis and prompt treatment of hyperoxaluria.
(in the urine)
Are There Different Types of Hyperoxaluria?
There are several types:
Primary Hyperoxaluria is an inherited (genetic) disease – you are born with it. It can present at any age and at any time. PH often goes underdiagnosed and is misdiagnosed. Recurrent kidney stones in adults or any kidney stone in a child is usually the most common sign that you might have PH.
Enteric Hypeoxaluria is a condition in which excess oxalate from foods is absorbed into the gastrointestinal (GI) tract which causes high levels of oxalate in the urine.
Dietary Hyperoxaluria is a result of a high intake of oxalate rich foods.
What Causes Primary Hyperoxaluria?
PH is a family of rare, genetic liver disorders that can damage the kidneys. The liver normally makes proteins, called enzymes, that prevent the body from making too much oxalate. In PH, the liver doesn’t create enough of this enzyme, or the enzyme doesn’t work properly.
Although kidney stones are the most common and often the first symptom of hyperoxaluria, not all individuals with hyperoxaluria will have kidney stones. If you experience the below signs and symptoms, you should further investigate to understand the cause, because it could be hyperoxaluria:
- Urinary tract infection
- Blood in the urine
- Kidney stones as a child, even only 1
- Failure to thrive (not growing adequately as a baby
- Recurrent kidney stones
- Nephrocalcinosis (finding crystals in kidney tissue)
- Kidney failure
- High levels of oxalate
Life Stage Manifestations
|Insufficient weight gain||Multiple kidney stones|
|Formation of kidney stones||Progressive kidney stones (including kidney failure)|
|Early end-stage renal failure||Multi-organ dysfunction|
Prevalence of Hyperoxaluria
Approximately 1 to 3 of every million people have Primary Hyperoxaluria (PH). Type 1 is the most common form, accounting for approximately 80% of cases. Types 2 and 3 each account for about 10% of cases
The prevalence of Enteric Hyperoxaluria (EH) has been estimated at 5-24% of all patients with gastrointestinal diseases associated with malabsorption. EH is a frequent complication of inflammatory bowel diseases (IBD), ileal resection and Roux-en-Y gastric bypass (RYGB) and is well-known to cause kidney stones, and nephrocalcinosis. EH can also contribute to chronic kidney disease (CKD) and kidney failure.
Inheritance and Genetics
A genetic disease or disorder is the result of changes, or mutations, in an individual’s DNA. A mutation is a change in the letters (DNA sequence) that make up a gene. This is sometimes referred to as a “spelling” mistake. To have an autosomal recessive disorder, you inherit two mutated genes, one from each parent.
PH is inherited in an autosomal recessive pattern. The genetic mutations that cause PH control the production of different enzymes found primarily in the liver in PH type I and PH type II, and in the kidney and liver in PH type III. The significance of the enzyme found in the kidney remains to be determined.