Hyperuricaemia or hyperuricemia is an abnormally high level of
uric acid
Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of ...
in the
blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the c ...
. In the pH conditions of body fluid, uric acid exists largely as urate, the ion form.
Serum uric acid concentrations greater than 6 mg/dL for females, 7 mg/dL for men, and 5.5 mg/dL for youth (under 18 years old) are defined as hyperuricemia.
The amount of urate in the body depends on the
balance
Balance or balancing may refer to:
Common meanings
* Balance (ability) in biomechanics
* Balance (accounting)
* Balance or weighing scale
* Balance as in equality or equilibrium
Arts and entertainment Film
* ''Balance'' (1983 film), a Bulgaria ...
between the amount of
purine
Purine is a heterocyclic compound, heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which includ ...
s eaten in food, the amount of urate synthesised within the body (e.g., through
cell turnover
The cell cycle, or cell-division cycle, is the series of events that take place in a cell that cause it to divide into two daughter cells. These events include the duplication of its DNA (DNA replication) and some of its organelles, and subs ...
), and the amount of urate that is excreted in urine or through the gastrointestinal tract.
[ Hyperuricemia may be the result of increased production of uric acid, decreased excretion of uric acid, or both increased production and reduced excretion.]
Signs and symptoms
Unless high blood levels of uric acid are determined in a clinical laboratory
A medical laboratory or clinical laboratory is a laboratory where tests are conducted out on clinical specimens to obtain information about the health of a patient to aid in diagnosis, treatment, and prevention of disease. Clinical Medical labor ...
, hyperuricemia may not cause noticeable symptoms in most people.[ Development of ]gout
Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of a red, tender, hot and swollen joint, caused by deposition of monosodium urate monohydrate crystals. Pain typically comes on rapidly, reaching maximal intensit ...
which is a painful, short-term disorder is the most common consequence of hyperuricemia, which causes deposition of uric acid crystals usually in joints of the extremities, but may also induce formation of kidney stone
Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine s ...
s, another painful disorder. Gout symptoms are typically inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
, swelling and redness of a joint, such as a toe or knee, accompanied by intense pain. Not all people with hyperuricemia develop gout.[
]
Causes
Many factors contribute to hyperuricemia, including genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar wor ...
, insulin resistance
Insulin resistance (IR) is a pathological condition in which cell (biology), cells fail to respond normally to the hormone insulin.
Insulin is a hormone that facilitates the transport of glucose from blood into cells, thereby reducing blood gluco ...
, hypertension
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...
, hypothyroidism
Hypothyroidism (also called ''underactive thyroid'', ''low thyroid'' or ''hypothyreosis'') is a disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormone. It can cause a number of symptoms, such as po ...
, chronic kidney disease
Chronic kidney disease (CKD) is a type of kidney disease in which a gradual loss of kidney function occurs over a period of months to years. Initially generally no symptoms are seen, but later symptoms may include leg swelling, feeling tired, vo ...
, obesity
Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's we ...
, diet
Diet may refer to:
Food
* Diet (nutrition), the sum of the food consumed by an organism or group
* Dieting, the deliberate selection of food to control body weight or nutrient intake
** Diet food, foods that aid in creating a diet for weight loss ...
, iron overload
Iron overload or hemochromatosis (also spelled ''haemochromatosis'' in British English) indicates increased total accumulation of iron in the body from any cause and resulting organ damage. The most important causes are hereditary haemochromatosi ...
, use of diuretic
A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics in ...
s (e.g. thiazide
Thiazide () refers to both a class of sulfur-containing organic molecules and a class of diuretics based on the chemical structure of benzothiadiazine. The thiazide drug class was discovered and developed at Merck and Co. in the 1950s. The first ...
s, loop diuretic
Loop diuretics are diuretics that act on the Na-K-Cl cotransporter along the thick ascending limb of the loop of Henle in the kidney. They are primarily used in medicine to treat hypertension and edema often due to congestive heart failure or c ...
s), and excessive consumption of alcoholic beverage
An alcoholic beverage (also called an alcoholic drink, adult beverage, or a drink) is a drink that contains ethanol, a type of alcohol that acts as a drug and is produced by fermentation of grains, fruits, or other sources of sugar. The c ...
s. Of these, alcohol consumption is the most important.
Causes of hyperuricemia can be classified into three functional types: increased production of uric acid, decreased excretion of uric acid, and mixed type. Causes of increased production include high levels of purine
Purine is a heterocyclic compound, heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which includ ...
in the diet and increased purine metabolism
Purine metabolism refers to the metabolic pathways to synthesize and break down purines that are present in many organisms.
Biosynthesis
Purines are biologically synthesized as nucleotides and in particular as ribotides, i.e. bases attached to r ...
. Causes of decreased excretion include kidney disease, certain drugs, and competition for excretion between uric acid and other molecules. Mixed causes include high levels of alcohol and/or fructose
Fructose, or fruit sugar, is a Ketose, ketonic monosaccharide, simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galacto ...
in the diet, and starvation.
Increased production of uric acid
A purine-rich diet is a common but minor cause of hyperuricemia. Diet alone generally is not sufficient to cause hyperuricemia (see Gout
Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of a red, tender, hot and swollen joint, caused by deposition of monosodium urate monohydrate crystals. Pain typically comes on rapidly, reaching maximal intensit ...
). Foods high in the purines adenine
Adenine () ( symbol A or Ade) is a nucleobase (a purine derivative). It is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The three others are guanine, cytosine and thymine. Its derivati ...
and hypoxanthine
Hypoxanthine is a naturally occurring purine derivative. It is occasionally found as a constituent of nucleic acids, where it is present in the anticodon of tRNA in the form of its nucleoside inosine. It has a tautomer known as 6-hydroxypurine. Hyp ...
may aggravate symptoms of hyperuricemia.
Various studies have found higher uric acid levels to be positively associated with consumption of meat and seafood and inversely associated with dairy food consumption.
Myogenic hyperuricemia, as a result of the Purine Nucleotide Cycle
Purine is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which include substituted purines a ...
running when ATP reservoirs in muscle cells are low, is a common pathophysiologic feature of glycogenoses such as GSD-III, GSD-V and GSD-VII, as they are metabolic myopathies which impair the ability of ATP (energy) production for the muscle cells to use.[Mineo I, Kono N, Hara N, Shimizu T, Yamada Y, Kawachi M, Kiyokawa H, Wang YL, Tarui S. Myogenic hyperuricemia. A common pathophysiologic feature of glycogenosis types III, V, and VII. N Engl J Med. 1987 Jul 9;317(2):75-80. doi: 10.1056/NEJM198707093170203. PMID: 3473284.] In these metabolic myopathies, myogenic hyperuricemia is exercise-induced; inosine, hypoxanthine and uric acid increase in plasma after exercise and decrease over hours with rest. Excess IMP (inosine monophosphate) is converted into uric acid. IMP → Inosine → Hypoxanthine → Xanthine → Uric Acid
Hyperuricemia experienced as gout
Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of a red, tender, hot and swollen joint, caused by deposition of monosodium urate monohydrate crystals. Pain typically comes on rapidly, reaching maximal intensit ...
is a common complication of solid organ transplant. Apart from normal variation (with a genetic component), tumor lysis syndrome
Tumor lysis syndrome (TLS) is a group of metabolic abnormalities that can occur as a complication from the treatment of cancer, where large amounts of tumor cells are killed off ( lysed) from the treatment, releasing their contents into the blood ...
produces extreme levels of uric acid, mainly leading to kidney failure
Kidney failure, also known as end-stage kidney disease, is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as eit ...
. The Lesch–Nyhan syndrome
Lesch–Nyhan syndrome (LNS) is a rare inherited disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT). This deficiency occurs due to mutations in the ''HPRT1'' gene located on the X chromosome. LNS ...
is also associated with extremely high levels of uric acid.
Decreased excretion of uric acid
The principal drugs that contribute to hyperuricemia by decreased excretion are the primary antiuricosurics. Other drugs and agents include diuretic
A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics in ...
s, salicylate
Salicylic acid is an organic compound with the formula HOC6H4CO2H. A colorless, bitter-tasting solid, it is a precursor to and a metabolite of aspirin (acetylsalicylic acid). It is a plant hormone, and has been listed by the EPA Toxic Substance ...
s, pyrazinamide
Pyrazinamide is a medication used to treat tuberculosis. For active tuberculosis, it is often used with rifampicin, isoniazid, and either streptomycin or ethambutol. It is not generally recommended for the treatment of latent tuberculosis. It i ...
, ethambutol
Ethambutol (EMB, E) is a medication primarily used to treat tuberculosis. It is usually given in combination with other tuberculosis medications, such as isoniazid, rifampicin and pyrazinamide. It may also be used to treat ''Mycobacterium avi ...
, nicotinic acid
Niacin, also known as nicotinic acid, is an organic compound and a form of vitamin B3, an essential human nutrient. It can be manufactured by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variet ...
, ciclosporin
Ciclosporin, also spelled cyclosporine and cyclosporin, is a calcineurin inhibitor, used as an immunosuppressant medication. It is a natural product. It is taken orally or intravenously for rheumatoid arthritis, psoriasis, Crohn's disease, ...
, 2-ethylamino-1,3,4-thiadiazole, and cytotoxic agent
Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa'').
Cell physiology
Treating cell ...
s.
The gene SLC2A9
Solute carrier family 2, facilitated glucose transporter member 9 is a protein that in humans is encoded by the ''SLC2A9'' gene.
This gene encodes a member of the SLC2A facilitative glucose transporter family. Members of this family play a signifi ...
encodes a protein that helps to transport uric acid in the kidney. Several single nucleotide polymorphism
In genetics, a single-nucleotide polymorphism (SNP ; plural SNPs ) is a germline substitution of a single nucleotide at a specific position in the genome. Although certain definitions require the substitution to be present in a sufficiently larg ...
s of this gene are known to have a significant correlation with blood uric acid. Hyperuricemia cosegregating with osteogenesis imperfecta
Osteogenesis imperfecta (; OI), colloquially known as brittle bone disease, is a group of genetic disorders that all result in bones that break easily. The range of symptoms—on the skeleton as well as on the body's other organs—may be mi ...
has been shown to be associated with a mutation in GPATCH8 using exome sequencing
Exome sequencing, also known as whole exome sequencing (WES), is a genomic technique for sequencing all of the protein-coding regions of genes in a genome (known as the exome). It consists of two steps: the first step is to select only the subse ...
A ketogenic diet
The ketogenic diet is a high- fat, adequate-protein, low-carbohydrate dietary therapy that in conventional medicine is used mainly to treat hard-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than ca ...
impairs the ability of the kidney to excrete uric acid, due to competition for transport between uric acid and ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bo ...
s.
Elevated blood lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...
is significantly correlated with both impaired kidney function and hyperuricemia (although the causal relationship among these correlations is not known). In a study of over 2500 people resident in Taiwan, a blood lead level
Blood lead level (BLL), is a measure of the amount of lead in the blood. Lead is a toxic heavy metal and can cause neurological damage, especially among children, at any detectable level. High lead levels cause decreased vitamin D and haemoglob ...
exceeding 7.5 microg/dL (a small elevation) had odds ratio
An odds ratio (OR) is a statistic that quantifies the strength of the association between two events, A and B. The odds ratio is defined as the ratio of the odds of A in the presence of B and the odds of A in the absence of B, or equivalently (due ...
s of 1.92 (95% CI: 1.18-3.10) for renal dysfunction and 2.72 (95% CI: 1.64-4.52) for hyperuricemia.
Mixed type
Causes of hyperuricemia that are of mixed type have a dual action, both increasing production and decreasing excretion of uric acid.
High intake of alcohol (ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl ...
), a significant cause of hyperuricemia, has a dual action that is compounded by multiple mechanisms. Ethanol increases production of uric acid by increasing production of lactic acid
Lactic acid is an organic acid. It has a molecular formula . It is white in the solid state and it is miscible with water. When in the dissolved state, it forms a colorless solution. Production includes both artificial synthesis as well as natu ...
, hence lactic acidosis
Lactic acidosis is a medical condition characterized by a build-up of lactate (especially -lactate) in the body, with formation of an excessively low pH in the bloodstream. It is a form of metabolic acidosis, in which excessive acid accumulates ...
. Ethanol also increases the plasma concentrations of hypoxanthine and xanthine via the acceleration of adenine nucleotide degradation, and is a possible weak inhibitor of xanthine dehydrogenase. As a byproduct of its fermentation process, beer
Beer is one of the oldest and the most widely consumed type of alcoholic drink in the world, and the third most popular drink overall after water and tea. It is produced by the brewing and fermentation of starches, mainly derived from ce ...
additionally contributes purines. Ethanol decreases excretion of uric acid by promoting dehydration
In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mil ...
and (rarely) clinical ketoacidosis
Ketoacidosis is a metabolic state caused by uncontrolled production of ketone bodies that cause a metabolic acidosis. While ketosis refers to any elevation of blood ketones, ketoacidosis is a specific pathologic condition that results in changes ...
.
High dietary intake of fructose
Fructose, or fruit sugar, is a Ketose, ketonic monosaccharide, simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galacto ...
contributes significantly to hyperuricemia. In a large study in the United States, consumption of four or more sugar-sweetened soft drink
A soft drink (see § Terminology for other names) is a drink that usually contains water (often carbonated), a sweetener, and a natural and/or artificial flavoring. The sweetener may be a sugar, high-fructose corn syrup, fruit juice, a su ...
s per day gave an odds ratio of 1.82 for hyperuricemia. Increased production of uric acid is the result of interference, by a product of fructose metabolism, in purine metabolism. This interference has a dual action, both increasing the conversion of ATP to inosine
Inosine is a nucleoside that is formed when hypoxanthine is attached to a ribose ring (also known as a ribofuranose) via a β-N9-glycosidic bond. It was discovered in 1965 in analysis of RNA transferase.
Inosine is commonly found in tRNAs and is e ...
and hence uric acid and increasing the synthesis of purine. Fructose also inhibits the excretion of uric acid, apparently by competing with uric acid for access to the transport protein SLC2A9. The effect of fructose in reducing excretion of uric acid is increased in people with a hereditary (genetic) predisposition toward hyperuricemia and/or gout.
Starvation
Starvation is a severe deficiency in caloric energy intake, below the level needed to maintain an organism's life. It is the most extreme form of malnutrition. In humans, prolonged starvation can cause permanent organ damage and eventually, dea ...
causes the body to metabolize its own (purine-rich) tissues for energy. Thus, like a high purine diet, starvation increases the amount of purine converted to uric acid. A very low calorie diet
A very-low-calorie diet (VLCD), also known as semistarvation diet and crash diet, is a type of diet with very or extremely low daily food energy consumption. Often described as a fad diet, it is defined as a diet of per day or less. Modern medica ...
lacking in carbohydrate
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ma ...
s can induce extreme hyperuricemia; including some carbohydrate (and reducing the protein) reduces the level of hyperuricemia. Starvation also impairs the ability of the kidney to excrete uric acid, due to competition for transport between uric acid and ketones.
Diagnosis
Hyperuricemia can be detected using blood and urine tests.
Treatment
Medications that aim to lower the uric acid concentration
Medication
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...
s used to treat hyperuricemia are divided into two categories: xanthine oxidase inhibitor A xanthine oxidase inhibitor is any substance that inhibits the activity of xanthine oxidase, an enzyme involved in purine metabolism. In humans, inhibition of xanthine oxidase reduces the production of uric acid, and several medications that inhi ...
s and uricosuric Uricosuric medications (drugs) are substances that increase the excretion of uric acid in the urine, thus reducing the concentration of uric acid in blood plasma. In general, this effect is achieved by action on the proximal tubule of the kidney. ...
s. For people who have recurring attacks of gout, one of these two categories of drugs is recommended. The evidence for people with asymptomatic hyperuricaemia to take these medications is not clear.
Xanthine oxidase inhibitors
Xanthine oxidase inhibitors, including allopurinol
Allopurinol is a medication used to decrease high blood uric acid levels. It is specifically used to prevent gout, prevent specific types of kidney stones and for the high uric acid levels that can occur with chemotherapy. It is taken by mouth ...
, febuxostat
Febuxostat, sold under the brand names Uloric and Adenuric among others, is a medication used long-term to treat gout due to high uric acid levels. It is generally recommended only for people who cannot take allopurinol. When initially started, m ...
and topiroxostat, decrease the production of uric acid, by interfering with xanthine oxidase
Xanthine oxidase (XO, sometimes XAO) is a form of xanthine oxidoreductase, a type of enzyme that generates reactive oxygen species. These enzymes catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthin ...
.
Uricosurics
Uricosuric agents (benzbromarone
Benzbromarone is a uricosuric agent and non-competitive inhibitor of xanthine oxidase used in the treatment of gout, especially when allopurinol, a first-line treatment, fails or produces intolerable adverse effects. It is structurally related to ...
, benziodarone, probenecid
Probenecid, also sold under the brand name Probalan, is a medication that increases uric acid excretion in the urine. It is primarily used in treating gout and hyperuricemia.
Probenecid was developed as an alternative to caronamide to competitive ...
, lesinurad
Lesinurad (brand name Zurampic) is a urate transporter inhibitor for treating high blood uric acid levels associated with gout. It is only recommended together with either allopurinol or febuxostat when these medications are not sufficient.
I ...
, sulfinpyrazone, ethebencid, zoxazolamine
Zoxazolamine (INN, USAN, BAN) (brand name Contrazole, Deflexol, Flexin, Miazol, Uri-Boi, Zoxamine, Zoxine) is a muscle relaxant that is no longer marketed. It was synthesized in 1953 and introduced clinically in 1955 but was withdrawn due to he ...
, and ticrynafen) increase the excretion of uric acid, by reducing the reabsorption of uric acid once it has been filtered out of the blood by the kidneys.
Some of these medications are used as indicated
In medicine, an indication is a valid reason to use a certain test, medication, procedure, or surgery. There can be multiple indications to use a procedure or medication. An indication can commonly be confused with the term diagnosis. A diagnosis ...
, others are used off-label
Off-label use is the use of pharmaceutical drugs for an unapproved indication or in an unapproved age group, dosage, or route of administration. Both prescription drugs and over-the-counter drugs (OTCs) can be used in off-label ways, although m ...
. In people receiving hemodialysis
Hemodialysis, also spelled haemodialysis, or simply dialysis, is a process of purifying the blood of a person whose kidneys are not working normally. This type of dialysis achieves the extracorporeal removal of waste products such as creatinin ...
, sevelamer
Sevelamer (rINN) is a phosphate binding medication used to treat hyperphosphatemia in patients with chronic kidney disease. When taken with meals, it binds to dietary phosphate and prevents its absorption. Sevelamer was invented and developed by ...
can significantly reduce serum uric acid, apparently by adsorbing urate in the gut. In women, use of combined oral contraceptive pill
The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as "the pill", is a type of birth control that is designed to be taken orally by women. The pill contains two important hormones: progest ...
s is significantly associated with lower serum uric acid. Following Le Chatelier's principle
Le Chatelier's principle (pronounced or ), also called Chatelier's principle (or the Equilibrium Law), is a principle of chemistry used to predict the effect of a change in conditions on chemical equilibria. The principle is named after French c ...
, lowering the blood concentration of uric acid may permit any existing crystals of uric acid to gradually dissolve into the blood, whence the dissolved uric acid can be excreted. Maintaining a lower blood concentration of uric acid similarly should reduce the formation of new crystals. If the person has chronic gout
Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of a red, tender, hot and swollen joint, caused by deposition of monosodium urate monohydrate crystals. Pain typically comes on rapidly, reaching maximal intensit ...
or known tophi
A tophus (Latin: "stone", plural tophi) is a deposit of monosodium urate crystals, in people with longstanding high levels of uric acid in the blood, a condition known as hyperuricemia. Tophi are pathognomonic for the disease gout. Most people wit ...
, then large quantities of uric acid crystals may have accumulated in joints and other tissues, and aggressive and/or long duration use of medications may be needed. Precipitation of uric acid crystals, and conversely their dissolution, is known to be dependent on the concentration of uric acid in solution, pH, sodium concentration, and temperature.
Non-medication treatments for hyperuricemia include a low purine
Purine is a heterocyclic compound, heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which includ ...
diet (see Gout
Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of a red, tender, hot and swollen joint, caused by deposition of monosodium urate monohydrate crystals. Pain typically comes on rapidly, reaching maximal intensit ...
) and a variety of dietary supplements. Treatment with lithium
Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid el ...
salts has been used as lithium improves uric acid solubility.
pH
Serum pH is neither safely nor easily altered. Therapies that alter pH principally alter the pH of urine, to discourage a possible complication of uricosuric therapy: formation of uric acid kidney stones due to increased uric acid in the urine (see Nephrolithiasis
Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine s ...
). Medications that have a similar effect include acetazolamide
Acetazolamide, sold under the trade name Diamox among others, is a medication used to treat glaucoma, epilepsy, altitude sickness, periodic paralysis, idiopathic intracranial hypertension (raised brain pressure of unclear cause), urine alkalin ...
.
Temperature
Low temperature is a reported trigger of acute gout. An example would be a day spent standing in cold water, followed by an attack of gout the next morning. This is believed to be due to temperature-dependent precipitation of uric acid crystals in tissues at below normal temperature. Thus, one aim of prevention is to keep the hands and feet warm, and soaking in hot water may be therapeutic.
Prognosis
Increased levels predispose for gout
Gout ( ) is a form of inflammatory arthritis characterized by recurrent attacks of a red, tender, hot and swollen joint, caused by deposition of monosodium urate monohydrate crystals. Pain typically comes on rapidly, reaching maximal intensit ...
and, if very high, kidney failure
Kidney failure, also known as end-stage kidney disease, is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as eit ...
. Metabolic syndrome
Metabolic syndrome is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL).
Metabolic syndrome ...
often presents with hyperuricemia. Prognosis is good with regular consumption of allopurinol
Allopurinol is a medication used to decrease high blood uric acid levels. It is specifically used to prevent gout, prevent specific types of kidney stones and for the high uric acid levels that can occur with chemotherapy. It is taken by mouth ...
.
People with gout, and by inference hyperuricemia, are significantly less likely to develop Parkinson's disease
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...
, unless they also require diuretic
A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics in ...
s.
See also
* Hypouricemia
Hypouricemia or hypouricaemia is a level of uric acid in blood serum that is below normal. In humans, the normal range of this blood component has a lower threshold set variously in the range of 2 mg/dL to 4 mg/dL, while the upper thres ...
* Hyperuricosuria
Hyperuricosuria is a medical term referring to the presence of excessive amounts of uric acid in the urine. For men this is at a rate greater than 800 mg/day, and for women, 750 mg/day. Notable direct causes of hyperuricosuria are dissol ...
* Metabolic Myopathies (myogenic hyperuricemia)
* Purine Nucleotide Cycle
Purine is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which include substituted purines a ...
* Uric Acid
Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of ...
References
Further reading
*
External links
GeneReviews/NCBI/NIH/UW entry on UMOD-Related Kidney Disease Includes: Familial Juvenile Hyperuricemic Nephropathy, Medullary Cystic Kidney Disease 2
OMIM entries on UMOD-Related Kidney Disease Includes: Familial Juvenile Hyperuricemic Nephropathy, Medullary Cystic Kidney Disease 2
GeneReviews/NCBI/NIH/UW entry on Familial Juvenile Hyperuricemic Nephropathy Type 2
OMIM entries on Familial Juvenile Hyperuricemic Nephropathy Type 2
{{Authority control
Uric acid
Abnormal clinical and laboratory findings for blood
Inborn errors of purine-pyrimidine metabolism