Hyperoxaluria is a serious disease characterized by increased excretion of oxalic acid in urine. Oxalic acid is a metabolic end product that is normally rapidly degraded into carbon dioxide and water. However, if this degradation does not work properly, or if too much oxalic acid enters the body through the diet, then calcium oxalates which are difficult to dissolve with calcium can be deposited as urinary stones in the urine-draining organs.
As a result, the kidneys in particular are damaged. There are both primary and secondary forms of hyperoxaluria. Thus, primary hyperoxaluria are always genetic and can be divided into three types. In all three types there are enzyme defects which lead to increased oxalic acid formation or reduced oxalic acid degradation in the organism. The oxalic acid must be excreted in the urine.
It combines with calcium to calcium oxalate, which crystallizes both in the kidneys and sometimes in other organs. Secondary hyperoxaluria is often associated with other metabolic diseases that lead to increased levels of calcium in the blood. Furthermore, it is also caused by an increased intake of oxalic acid foods.
The primary hyperoxaluria has genetic defects. Thus, type 1 primary hyperoxaluria is an autosomal recessive metabolic disease characterized by a defect in the liver enzyme glyoxylate aminotransferase. The enzyme is responsible for the conversion of glyoxylate to glycine.
When this enzyme is inoperable, glyoxylate accumulates, which is then degraded into oxalic acid. Also in primary type II hyperoxaluria (PH II), the concentration of oxalic acid is increased. Here the enzyme glyoxylate reductase / hydroxypyruvate reductase is defective. As a result, oxalate accumulates because glyoxylate can not be converted.
In PH III, the enzyme 2-keto-4-hydroxy-glutarate aldolase is inoperable, which also leads to an increased concentration of oxalic acid. The oxalic acid must be excreted in the urine. At very high concentrations of oxalic acid, however, it precipitates as calcium salt and forms urinary stones in the kidneys. The constant deposition of calcium oxalate causes kidney inflammation and scarring reactions that eventually impair kidney function.
There is also a systemic oxalosis. Oxalose precipitates calcium oxalate in many other organs as its concentration of oxalic acid in the blood is increased. Affected are among other things, vascular walls, eyes, heart muscle, skin, bones or the central nervous system. This results in typical impairments of the affected organs such as blindness, bone oxalysis, cardiac arrhythmias or anemia.
Organ failure even threatens death. The secondary forms of hyperoxaluria are often based on other metabolic diseases associated with increased release of calcium. Calcium then binds increasingly with existing oxalic acid to oxalates, which in turn can precipitate.
This includes hyperparathyroidism, Cushing's disease, sarcoidosis, bone metastases, multiple myeloma, and vitamin D overdose. In addition, secondary hyperoxaluria can also develop with over intake of oxalic acid through the diet. Especially oxalic acid is present in rhubarb, sorrel, spinach or cocoa products.
The symptoms of hyperoxaluria can be manifold. The course of the disease can vary greatly even among the same individuals, even in the same form. Typical is the increased concentration of oxalates in the urine. Mostly it comes to stone formation in the urine laxative organs.
In primary hyperoxaluria, the formation of oxalate in the kidneys and other organs can be so severe that significant kidney damage and other tissue damage occurs as early as infancy. Other people with primary hyperoxaluria may experience only occasional kidney stones at older ages. Overall, there are symptoms characterized by severe renal dysfunction, urinary calcifications, renal colic, hematuria, fever, and kidney failure.
When the kidneys are no longer working effectively, the levels of oxalate in the blood also increase, which can lead to the development of oxalosis in various tissues. It then leads to cardiac arrhythmia, hypertension, partial tissue necrosis (gangrene) and limited mobility of the joints.
The diagnosis of hyperoxaluria is made by measuring the oxalic acid concentration in the urine. Oxalic acid excretion should not exceed 40 milligrams per day.
Hyperoxaluria causes kidney problems in most patients. Other tissues in the patient's body may be affected by the disease. It increasingly leads to stone formation in the kidneys and thus to considerable pain in the patient. The tissue on the kidneys and other organs can be severely damaged by hyperoxaluria, so that it may be necessary to work with restrictions on these organs.
Most patients also suffer from fever and a general malaise. In the worst case, complete renal failure may occur if the hyperoxaluria is not promptly treated by a physician. Furthermore, high blood pressure occurs, which in the worst case can lead to a heart attack. An untreated hyperoxaluria leads to a reduced life expectancy.
Acute emergencies can usually be treated with a high supply of fluid. In severe cases, however, the transplantation of various organs in the patient is necessary. This can lead to complications or other complaints. However, these depend on the exact circumstances of the disease and can not be generally predicted.
Symptoms and ailments such as urinary stones, renal colic or fever may be the cause of hyperoxaluria. A doctor should be consulted if the symptoms persist for longer than two to three days. If additional symptoms occur during the course of the illness, such as signs of hematuria or kidney dysfunction, the family doctor must be consulted immediately. For serious complications, such as cardiac arrhythmia or tissue necrosis, visit the hospital.
In severe cases, the emergency doctor should be called immediately. This is especially true when the symptoms occur suddenly and are associated with deficits. In this case, medical advice is best sought immediately. Individuals diagnosed with genetic defects are particularly susceptible to the development of hyperoxaluria. Similarly, people with Cushing's disease, sarcoidosis or hyperparathyroidism. Those who belong to these groups at risk, the best with these symptoms immediately to a doctor. In addition to the family doctor, a specialist in internal medicine or a nephrologist can be consulted.
Hyperoxaluria is first treated by increased hydration. Furthermore, inhibitors are administered which prevent the crystal formation of calcium oxalate. These include magnesium, citrate or bicarbonate. The urine is kept as alkaline as possible in order to keep calcium oxalate in solution.
In patients who are very sensitive to vitamin B6, pyridoxine is substituted to reduce the production of oxalate. These treatments may delay the course of severe primary hyperoxaluria. However, in many cases combined kidney-to-liver transplantation is needed as a child to prevent enzyme-induced oxalate formation and save patients' lives.
The prognosis of hyperoxaluria is very different. Untreated, it can take a very heavy course. A particularly poor prognosis is the type I primary hyperoxaluria. It is genetically conditioned like the other two primary forms of the disease. Secondary hyperoxaluria is in turn based on another disorder.
Common to all hyperoxaluria, however, is the deposition of calcium oxalate in the organism. Due to the high degree of saturation with calcium oxalate in the urine, the crystals precipitate especially in the kidneys and cause severe kidney dysfunction in the course of time. The oxalates appear as kidney stones, which constantly damage the kidney tissue. The disease can also run mildly into old age, with only occasional kidney stones are diagnosed. However, in other cases, such as primary type 1 hyperoxaluria, severe kidney damage occurs early in childhood. Without treatment, hyperoxaluria is often fatal.
Oxalose (deposition of oxalate crystals) often spreads to the whole organism after the functional impairment of the kidneys has increased. Heart muscle, blood vessels, eyes, skin, bones and central nervous system are often affected. As a result, complications such as cardiac arrhythmia, blindness, untreatable anemia, vascular disease or oxalate bone disease occur. Partly the illnesses are fatal. In many cases, even intensive therapy with high fluid administration and drug-induced inhibition of crystal formation can only delay the course of the disease, but not prevent it. Sometimes a combined liver and kidney transplant needs to be done.
Prevention of primary hyperoxaluria is not possible because it is genetic. With a corresponding disposition oxalic acid-containing foods should be avoided. Overall, the consumption of very large amounts of rhubarb, spinach or cocoa-containing products should be limited as they may eventually lead to secondary hyperoxaluria.
In the case of hyperoxaluria, the person concerned is primarily dependent on a rapid diagnosis with the subsequent treatment in order to prevent further complications and complaints from this disease. The sooner a doctor is visited, the better is usually the further course of the disease. The person concerned should therefore contact a doctor at the first symptoms and signs of hyperoxaluria, as it can also lead to death in the worst case.
A self-healing can not occur in this disease, so that treatment is always necessary. The measures of aftercare are limited. In most cases, treatment of hyperoxaluria is medicated. It is important to ensure a correct dosage and also on a regular intake.
Especially in children, parents must check the correct intake and dosage. For side effects or interactions, first contact a doctor. Furthermore, regular examinations of the internal organs are very important to detect damage to the internal organs and to treat it in a timely manner. Hyperoxaluria may therefore limit or significantly reduce the life expectancy of the person affected.
The complaints can be avoided in most cases relatively simply by a change in diet. However, even the early detection of the disease has a very positive effect on the course and can avoid discomfort and damage to the kidneys.
As a rule, the person concerned should abstain from oxalic acid-containing foods in case of hyperoxaluria. The intake of cocoa-containing products should be restricted as much as possible. Furthermore, the affected person must abstain in his diet on spinach or rhubarb. For the most part, hyperoxaluria does not represent a major limitation in the patient's daily routine and dietary intake. By taking pyridoxine, sufferers can reduce oxalate in the body. It is only to pay attention to regular intake, so it does not come to further complaints.
The acute complaints of the disease are treated most by an increased supply of fluid. Since the disease can also damage the kidneys or the heart, those affected should regularly participate in examinations. For mental health problems or depression, conversations with other people with hyperoxaluria or close associates and parents often help.