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A pH under 7.1 is an emergency, due to the risk of cardiac arrhythmias, and may warrant treatment with intravenous bicarbonate. Bicarbonate is given at 50-100 mmol at a time under scrupulous monitoring of the arterial blood gas readings. This intervention, however, has some serious complications in lactic acidosis, and in those cases, should be used with great care.
If the acidosis is particularly severe and/or intoxication may be present, consultation with the nephrology team is considered useful, as dialysis may clear both the intoxication and the acidosis.
Several medical treatments shift potassium ions from the bloodstream into the cellular compartment, thereby reducing the risk of complications. The effect of these measures tends to be short-lived, but may temporize the problem until potassium can be removed from the body.
- Insulin (e.g. intravenous injection of 10-15 units of regular insulin along with 50 ml of 50% dextrose to prevent the blood sugar from dropping too low) leads to a shift of potassium ions into cells, secondary to increased activity of the sodium-potassium ATPase. Its effects last a few hours, so it sometimes must be repeated while other measures are taken to suppress potassium levels more permanently. The insulin is usually given with an appropriate amount of glucose to prevent hypoglycemia following the insulin administration.
- Salbutamol (albuterol), a β-selective catecholamine, is administered by nebulizer (e.g. 10–20 mg). This medication also lowers blood levels of K by promoting its movement into cells.
- Sodium bicarbonate may be used with the above measures if it is believed the person has metabolic acidosis.
Intake of carbohydrates which must be converted to G6P to be utilized (e.g., galactose and fructose) should be minimized. Although elemental formulas are available for infants, many foods contain fructose or galactose in the forms of sucrose or lactose. Adherence becomes a contentious treatment issue after infancy.
Severe cases require hemodialysis or hemofiltration, which are the most rapid methods of removing potassium from the body. These are typically used if the underlying cause cannot be corrected swiftly while temporizing measures are instituted or there is no response to these measures.
Potassium can bind to agents in the gastrointestinal tract. Sodium polystyrene sulfonate with sorbitol (Kayexalate) has been approved for this use and can be given by mouth or rectally. However, careful clinical trials to demonstrate the effectiveness of sodium polystyrene are lacking, and use of sodium polystyrene sulfonate, particularly if with high sorbitol content, is uncommonly but convincingly associated with colonic necrosis. There are no systematic studies (>6 months) looking at the long-term safety of this medication. Another medication by the name of patiromer was approved in 2015.
Loop diuretics (furosemide, bumetanide, torasemide) and thiazide diuretics (e.g., chlorthalidone, hydrochlorothiazide, or chlorothiazide) can increase kidney potassium excretion in people with intact kidney function.
Fludrocortisone, a synthetic mineralocorticoid, can also increase potassium excretion by the kidney in patients with functioning kidneys. Trials of fludrocortisone in patients on dialysis have shown it to be ineffective.
Patiromer is a selective sorbent that is taken by mouth and works by binding free potassium ions in the gastrointestinal tract and releasing calcium ions for exchange, thus lowering the amount of potassium available for absorption into the bloodstream and increasing the amount that is excreted via the feces. The net effect is a reduction of potassium levels in the blood serum.
Persistent elevation of uric acid above 6.5 mg/dl warrants treatment with allopurinol to prevent uric acid deposition in kidneys and joints.
Because of the potential for impaired platelet function, coagulation ability should be checked and the metabolic state normalized before surgery. Bleeding time may be normalized with 1–2 days of glucose loading, and improved with ddavp. During surgery, iv fluids should contain 10% dextrose and no lactate.
A patient with GSD, type 1b was treated with a liver transplant at UCSF Medical Center in 1993 that resulted in the resolution of hypoglycemic episodes and the need for the patient to stay away from natural sources of sugar. Other patients have undergone this procedure as well with positive results. Although a liver transplant resulted in the resolution of hypoglycemia it did not however resolve the chronic neutropenia and the risk of infection among patients.
Potassium replacement is often required as the metabolic problems are corrected. It is generally replaced at a rate 10 mEq per hour as long as there is adequate urinary output.
Treatment of HHS begins with reestablishing tissue perfusion using intravenous fluids. People with HHS can be dehydrated by 8 to 12 liters. Attempts to correct this usually take place over 24 hours with initial rates of normal saline often in the range of 1 L/h for the first few hours or until the condition stabilizes.
The goal for treatment of GSD type 0 is to avoid hypoglycemia. This is accomplished by avoiding fasting by eating every 3-4 hours during the day. At night, uncooked corn starch can be given because it is a complex glucose polymer. This will be acted on slowly by pancreatic amylase and glucose will be absorbed over a 6 hour period.
This is relatively straightforward. It involves correction of the acidemia with oral sodium bicarbonate, sodium citrate or potassium citrate. This will correct the acidemia and reverse bone demineralisation. Hypokalemia and urinary stone formation and nephrocalcinosis can be treated with potassium citrate tablets which not only replace potassium but also inhibit calcium excretion and thus do not exacerbate stone disease as sodium bicarbonate or citrate may do.
Ketosis is deliberately induced by use of a ketogenic diet as a medical intervention in cases of intractable epilepsy. Other uses of low-carbohydrate diets remain controversial. Carbohydrate deprivation to the point of ketosis has been argued to have both negative and positive effects on health.
Direct removal of lactate from the body (e.g. with hemofiltration) is difficult, with limited evidence for benefit. In type A lactic acidosis, treatment consists of effective management of the underlying cause, and limited evidence supports the use of sodium bicarbonate solutions to improve the pH (which is associated with increased carbon dioxide generation and may reduce the calcium levels).
In type B lactic acidosis produced by medication, withdrawal of the medication may be necessary to resolve the lactic acidosis.
Lactic acidosis in the context of mitochondrial disorders (type B3) may be treated with a ketogenic diet and possibly with dichloroacetate (DCA), although this may be complicated by peripheral neuropathy and has a weak evidence base.
To treat people with a deficiency of this enzyme, they must avoid needing gluconeogenesis to make glucose. This can be accomplished by not fasting for long periods, and eating high-carbohydrate food. They should avoid fructose containing foods (as well as sucrose which breaks down to fructose).
As with all single-gene metabolic disorders, there is always hope for genetic therapy, inserting a healthy copy of the gene into existing liver cells.
The administration of sodium bicarbonate solution to rapidly improve the acid levels in the blood is controversial. There is little evidence that it improves outcomes beyond standard therapy, and indeed some evidence that while it may improve the acidity of the blood, it may actually worsen acidity inside the body's cells and increase the risk of certain complications. Its use is therefore discouraged, although some guidelines recommend it for extreme acidosis (pH<6.9), and smaller amounts for severe acidosis (pH 6.9–7.0).
The underlying cause determines the prognosis of lactic acidosis. In sepsis, elevated lactate levels correlate with mortality. The mortality of lactic acidosis in people taking metformin was previously reported to be 50%, but in more recent reports this was closer to 25%.
A diet with carefully controlled levels of the amino acids leucine, isoleucine, and valine must be maintained at all times in order to prevent neurological damage. Since these three amino acids occur in all natural protein, and most natural foods contain some protein, any food intake must be closely monitored, and day-to-day protein intake calculated on a cumulative basis, to ensure individual tolerance levels are not exceeded at any time. As the MSUD diet is so protein-restricted, and adequate protein is a requirement for all humans, tailored metabolic formula containing all the other essential amino acids, as well as any vitamins, minerals, omega-3 fatty acids and trace elements (which may be lacking due to the limited range of permissible foods), are an essential aspect of MSUD management. These complement the MSUD patient's natural food intake to meet normal nutritional requirements without causing harm. If adequate calories cannot be obtained from natural food without exceeding protein tolerance, specialised low protein products such as starch-based baking mixtures, imitation rice and pasta may be prescribed, often alongside a protein-free carbohydrate powder added to food and/or drink, and increased at times of metabolic stress. Some patients with MSUD may also improve with administration of high doses of thiamine, a cofactor of the enzyme that causes the condition.
Patients with propionic acidemia should be started as early as possible on a low protein diet. In addition to a protein mixture that is devoid of methionine, threonine, valine, and isoleucine, the patient should also receive -carnitine treatment and should be given antibiotics 10 days per month in order to remove the intestinal propiogenic flora. The patient should have diet protocols prepared for him with a “well day diet” with low protein content, a “half emergency diet” containing half of the protein requirements, and an “emergency diet” with no protein content. These patients are under the risk of severe hyperammonemia during infections that can lead to comatose states.
Liver transplant is gaining a role in the management of these patients, with small series showing improved quality of life.
Potassium levels can fluctuate severely during the treatment of DKA, because insulin decreases potassium levels in the blood by redistributing it into cells via increased sodium-potassium pump activity. A large part of the shifted extracellular potassium would have been lost in urine because of osmotic diuresis. Hypokalemia (low blood potassium concentration) often follows treatment. This increases the risk of dangerous irregularities in the heart rate. Therefore, continuous observation of the heart rate is recommended, as well as repeated measurement of the potassium levels and addition of potassium to the intravenous fluids once levels fall below 5.3 mmol/l. If potassium levels fall below 3.3 mmol/l, insulin administration may need to be interrupted to allow correction of the hypokalemia.
Although the etiology is unconfirmed, transient hyperammonemia is known to be caused by increased levels of ammonia in the blood stream, as well as a failure of the urea cycle to convert enough of the ammonia into urea. Since transamination of proteins is a leading producer of ammonia, protein restriction may be recommended as a therapy to reduce the symptoms of the episode. THAN can also be treated by avoiding amino acids in TPN or total parenteral nutrition or by giving a high caloric diet to limit catabolism of the tissues and therefore to minimize the breakdown of endogenous protein. The most common treatments are dialysis (both peritoneal and hemodialysis), sodium benzoate, and arginine. Sodium Benzoate combines with glycine to be excreted in the form of hippuric acid. The goal of these treatments is to convert nitrogen to a compound that can be excreted more easily.
Usually MSUD patients are monitored by a dietitian. Liver transplantation is another treatment option that can completely and permanently normalise metabolic function, enabling discontinuation of nutritional supplements and strict monitoring of biochemistry and caloric intake, relaxation of MSUD-related lifestyle precautions, and an unrestricted diet. This procedure is most successful when performed at a young age, and weaning from immunosuppressants may even be possible in the long run. However, the surgery is a major undertaking requiring extensive hospitalisation and rigorous adherence to a tapering regime of medications. Following transplant, the risk of periodic rejection will always exist, as will the need for some degree of lifelong monitoring in this respect. Despite normalising clinical presentation, liver transplantation is not considered a cure for MSUD. The patient will still carry two copies of the mutated BKAD gene in each of their own cells, which will consequently still be unable to produce the missing enzyme. They will also still pass one mutated copy of the gene on to each of their biological children. As a major surgery the transplant procedure itself also carries standard risks, although the odds of its success are greatly elevated when the only indication for it is an inborn error of metabolism. In absence of a liver transplant, the MSUD diet must be adhered to strictly and permanently. However, in both treatment scenarios, with proper management, those afflicted are able to live healthy, normal lives without suffering the severe neurological damage associated with the disease.
There is no proven treatment for congenital lactic acidosis. Treatments that are occasionally used or that are under investigation include the ketogenic diet and dichloroacetate. Other treatments aim to relieve symptoms – for example, anticonvulsants may be used to relieve seizures.
The mortality rate for THAN is relatively high unless immediate treatment is obtained. The duration of hyperammonemia is directly correlated to morbidity as well as the associated neurological conditions. After the first hyperammonemic episode, there is no increased risk for future hyperammonemic episodes, and normal protein consumption can be continued.
Causes include:
The newest mnemonic was proposed in "The Lancet" reflecting current causes of anion gap metabolic acidosis:
- G — glycols (ethylene glycol & propylene glycol)
- O — oxoproline, a metabolite of paracetamol
- L — L-lactate, the chemical responsible for lactic acidosis
- D — D-lactate
- M — methanol
- A — aspirin
- R — renal failure
- K — ketoacidosis, ketones generated from starvation, alcohol, and diabetic ketoacidosis
The mnemonic MUDPILES is commonly used to remember the causes of increased anion gap metabolic acidosis.
- M — Methanol
- U — Uremia (chronic kidney failure)
- D — Diabetic ketoacidosis
- P — Paracetamol, Propylene glycol (used as an inactive stabilizer in many medications; historically, the "P" also stood for Paraldehyde, though this substance is not commonly used today)
- I — Infection, Iron, Isoniazid (which can cause lactic acidosis in overdose), Inborn errors of metabolism (an especially important consideration in pediatric patients)
- L — Lactic acidosis
- E — Ethylene glycol (Note: Ethanol is sometimes included in this mnemonic as well, although the acidosis caused by ethanol is actually primarily due to the increased production of lactic acid found in such intoxication.)
- S — Salicylates
Another frequently used mnemonic is KARMEL.
- K — Ketoacidosis
- A — aspirin
- R — Renal failure
- M — Methanol
- E — Ethylene glycol
- L — Lactic acidosis
Another frequently used mnemonic is KULT.
- K — Ketoacidosis (DKA, AKA)
- U — Uremia
- L — Lactic acidosis
- T — Toxins (Ethylene glycol, methanol, as well as drugs, such as aspirin, Metformin)
The preferred mnemonic of D. Robert Dufour, the chief of the Pathology and Laboratory Medicine Service, Veterans Affairs Medical Center, is DUMPSALE, which omits the I of MUDPILES as the proposed values of *I* are exceedingly rare in clinical practice.
- D — Diabetic ketoacidosis
- U — Uremia
- M — Methanol
- P — Paraldehyde
- S — Salicylates
- A — Alcoholic ketoacidosis
- L — Lactic acidosis
- E — Ethylene Glycol
The mnemonic for the [rare, in comparison] toxins is ACE GIFTs: Aspirin, Cyanide, Ethanolic ketosis, Glycols [ ethylene and propylene ], Isoniazid, Ferrous iron, Toluene. Most of these cause a lactic acidosis.
Some clinicians regard eliminating carbohydrates as unhealthy and dangerous. However, it is not necessary to eliminate carbohydrates from the diet completely to achieve ketosis. Other clinicians regard ketosis as a safe biochemical process that occurs during the fat-burning state. Ketosis, which is accompanied by gluconeogenesis (the creation of glucose de novo from pyruvate), is the specific state that concerns some clinicians. However, it is unlikely for a normally functioning person to reach life-threatening levels of ketosis, defined as serum beta-hydroxybutyrate (B-OHB) levels above 15 millimolar (mM) compared to ketogenic diets among non diabetics, which "rarely run serum B-OHB levels above 3 mM." This is avoided with proper basal secretion of pancreatic insulin. People who are unable to secrete basal insulin, such as type 1 diabetics and long-term type II diabetics, are liable to enter an unsafe level of ketosis, eventually resulting in a coma that requires emergency medical treatment. The anti-ketosis conclusions have been challenged by a number of doctors and advocates of low-carbohydrate diets, who dispute assertions that the body has a preference for glucose and that there are dangers associated with ketosis.
Treatment or management of organic acidemias vary; eg see methylmalonic acidemia, propionic acidemia, isovaleric acidemia, and maple syrup urine disease.
As of 1984 there were no effective treatments for all of the conditions, though treatment for some included a limited protein/high carbohydrate diet, intravenous fluids, amino acid substitution, vitamin supplementation, carnitine, induced anabolism, and in some cases, tube-feeding.
As of 1993 ketothiolase deficiency and other OAs were managed by trying to restore biochemical and physiologic homeostasis; common therapies included restricting diet to avoid the precursor amino acids and use of compounds to either dispose of toxic metabolites or increase enzyme activity.
When acidosis is present on blood tests, the first step in determining the cause is determining the anion gap. If the anion gap is high (>12 mEq/L), there are several potential causes.
High anion gap metabolic acidosis is a form of metabolic acidosis characterized by a high anion gap (a medical value based on the concentrations of ions in a patient's serum). An anion gap is usually considered to be high if it is over 12 mEq/L.
High anion gap metabolic acidosis is caused generally by acid produced by the body. More rarely, high anion gap metabolic acidosis may be caused by ingesting methanol or overdosing on aspirin. The Delta Ratio is a formula that can be used to assess elevated anion gap metabolic acidosis and to evaluate whether mixed acid base disorder (metabolic acidosis) is present.
The list of agents that cause high anion gap metabolic acidosis is similar to but broader than the list of agents that cause a serum osmolal gap.