Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
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.
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.
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.
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%.
In the United States, hyperkalemia is induced by lethal injection in capital punishment cases. Potassium chloride is the last of the three drugs administered and actually causes death. Injecting potassium chloride into the heart muscle disrupts the signal that causes the heart to beat. This same amount of potassium chloride would do no harm if taken orally and not injected directly into the blood.
The primary treatment goal is prevention of hypoglycemia and the secondary metabolic derangements by frequent feedings of foods high in glucose or starch (which is readily digested to glucose). To compensate for the inability of the liver to provide sugar, the total amount of dietary carbohydrate should approximate the 24-hour glucose production rate. The diet should contain approximately 65–70% carbohydrate, 10–15% protein, and 20–25% fat. At least a third of the carbohydrates should be supplied through the night, so that a young child goes no more than 3–4 hours without carbohydrate intake
In the last 30 years, two methods have been used to achieve this goal in young children: (1) continuous nocturnal gastric infusion of glucose or starch; and (2) night-time feedings of uncooked cornstarch. An elemental formula, glucose polymer, and/or cornstarch can be infused continuously through the night at a rate supplying 0.5–0.6 g/kg/h of glucose for an infant, or 0.3–0.4 for an older child. This method requires a nasogastric or gastrostomy tube and pump. Sudden death from hypoglycemia has occurred due to malfunction or disconnection, and periodic cornstarch feedings are now preferred to continuous infusion.
Cornstarch is an inexpensive way to provide gradually digested glucose. One tablespoon contains nearly 9 g carbohydrate (36 calories). Although it is safer, less expensive, and requires no equipment, this method does require that parents arise every 3–4 hours to administer the cornstarch. A typical requirement for a young child is 1.6 g/kg every 4 hours.
Long-term management should eliminate hypoglycemic symptoms and maintain normal growth. Treatment should achieve normal glucose, lactic acid, and electrolyte levels, and only mild elevations of uric acid and triglycerides.
The several different causes of lactic acidosis include:
- Genetic conditions
- Biotinidase deficiency, multiple carboxylase deficiency, or nongenetic deficiencies of biotin
- Diabetes mellitus and deafness
- Fructose 1,6-bisphosphatase deficiency
- Glucose-6-phosphatase deficiency
- GRACILE syndrome
- Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes
- Pyruvate dehydrogenase deficiency
- Pyruvate carboxylase deficiency
- Drugs
- Linezolid
- Phenformin
- Metformin
- Isoniazid toxicity
- Propofol
- Propylene glycol (D-lactic acidosis)
- Nucleoside reverse transcriptase inhibitors
- Abacavir/dolutegravir/lamivudine
- Emtricitabine/tenofovir
- Potassium cyanide (cyanide poisoning)
- Fialuridine
- Other
- Impaired delivery of oxygen to cells in the tissues (e.g., from impaired blood flow (hypoperfusion))
- Bleeding
- Polymyositis
- Ethanol toxicity
- Sepsis
- Shock
- Advanced liver disease
- Diabetic ketoacidosis
- Excessive exercise (overtraining)
- Regional hypoperfusion (e.g., bowel ischemia or marked cellulitis)
- Cancers such as Non-Hodgkin's and Burkitt lymphomas
- Pheochromocytoma
The most significant acute problem in childhood is a vulnerability to episodes of metabolic acidosis precipitated by minor illnesses. If a vomiting illness persists longer than 2–4 hours, the child should be seen and assessed for dehydration, acidosis, and hypoglycemia. If these are developing, intravenous fluids should be provided at a rate above maintenance. For mild acidosis, an effective fluid is 10% dextrose in ½ normal saline with 20 mEq/l KCl, but if acidosis is severe, 75–100 mEq/l and 20 mEq/l of K acetate can be substituted for the NaCl and KCl.
Sodium zirconium cyclosilicate (ZS-9) is an investigational selective oral sorbent that binds potassium in the gastrointestinal tract in exchange for sodium and hydrogen ions.
Causes of increased anion gap include:
- Lactic acidosis
- Ketoacidosis
- Chronic renal failure (accumulation of sulfates, phosphates, urea)
- Intoxication:
- Organic acids, salicylates, ethanol, methanol, formaldehyde, ethylene glycol, paraldehyde, isoniazid
- Sulfates, metformin
- Massive rhabdomyolysis
A mnemonic can also be used - MUDPILES
- M-Methanol
- U-Uremia (chronic kidney failure)
- D-Diabetic ketoacidosis
- P-Paraldehyde
- I-Infection, Iron, Isoniazid, Inborn errors of metabolism
- 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
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.
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.
In dairy cattle, ketosis is a common ailment that usually occurs during the first weeks after giving birth to a calf. Ketosis is in these cases sometimes referred to as "acetonemia". A study from 2011 revealed that whether ketosis is developed or not depends on the lipids a cow uses to create butterfat. Animals prone to ketosis mobilize fatty acids from adipose tissue, while robust animals create fatty acids from blood phosphatidylcholine (lecithin). Healthy animals can be recognized by high levels of milk glycerophosphocholine and low levels of milk phosphocholine. Point of care diagnostic tests are available and are reasonably useful.
In sheep, ketosis, evidenced by hyperketonemia with beta-hydroxybutyrate in blood over 0.7 mmol/L, occurs in pregnancy toxemia. This may develop in late pregnancy in ewes bearing multiple fetuses, and is associated with the considerable glucose demands of the conceptuses. In ruminants, because most glucose in the digestive tract is metabolized by rumen organisms, glucose must be supplied by gluconeogenesis, for which propionate (produced by rumen bacteria and absorbed across the rumen wall) is normally the principal substrate in sheep, with other gluconeogenic substrates increasing in importance when glucose demand is high or propionate is limited. Pregnancy toxemia is most likely to occur in late pregnancy because most fetal growth (and hence most glucose demand) occurs in the final weeks of gestation; it may be triggered by insufficient feed energy intake (anorexia due to weather conditions, stress or other causes), necessitating reliance on hydrolysis of stored triglyceride, with the glycerol moiety being used in gluconeogenesis and the fatty acid moieties being subject to oxidation, producing ketone bodies. Among ewes with pregnancy toxemia, beta-hydroxybutyrate in blood tends to be higher in those that die than in survivors. Prompt recovery may occur with natural parturition, Caesarean section or induced abortion. Prevention (through appropriate feeding and other management) is more effective than treatment of advanced stages of ovine ketosis.
In general, the cause of a hyperchloremic metabolic acidosis is a "loss of base", either a gastrointestinal loss or a renal loss.
- Gastrointestinal loss of bicarbonate ()
- Severe diarrhea (vomiting will tend to cause hypochloraemic alkalosis)
- Pancreatic fistula with loss of bicarbonate rich pancreatic fluid
- Nasojejunal tube losses in the context of small bowel obstruction and loss of alkaline proximal small bowel secretions
- Chronic laxative abuse
- Renal causes
- Proximal renal tubular acidosis with failure of resorption
- Distal renal tubular acidosis with failure of secretion
- Long-term use of a carbonic anhydrase inhibitor such as acetazolamide
- Other causes
- Ingestion of ammonium chloride, hydrochloric acid, or other acidifying salts
- The treatment and recovery phases of diabetic ketoacidosis
- Volume resuscitation with 0.9% normal saline provides a chloride load, so that infusing more than 3-4L can cause acidosis
- Hyperalimentation ("i.e.", total parenteral nutrition)
Hyperchloremic acidosis is a form of metabolic acidosis associated with a normal anion gap, a decrease in plasma bicarbonate concentration, and an increase in plasma chloride concentration (see anion gap for a fuller explanation). Although plasma anion gap is normal, this condition is often associated with an "increased" urine anion gap, due to the kidney's inability to secrete ammonia.
Insulin is given to reduce blood glucose concentration; however, as it also causes the movement of potassium into cells, serum potassium levels must be sufficiently high or dangerously low blood potassium levels may result. Once potassium levels have been verified to be greater than 3.3 mEq/l, then an insulin infusion of 0.1 units/kg/hr is started. The goal for resolution is a blood glucose of less than 200 mg/dL.
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.
In non-diabetic persons, ketonuria may occur during acute illness or severe stress. Approximately 15% of hospitalized patients may have ketonuria, even though they do not have diabetes. In a diabetic patient, ketone bodies in the urine suggest that the patient is not adequately controlled and that adjustments of medication, diet, or both should be made promptly. In the non diabetic patient, ketonuria reflects a reduced carbohydrate metabolism and an increased fat metabolism.
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.
The main causes of hypokalemic acidosis are systemic disorders that can be divided into:
- Carbonic anhydrase inhibitors such as acetazolamide
- Dialysis, in the post-treatment
- Diarrhea
- Renal tubular acidosis
- Treated DKA with insulin therapy
- VIPoma
Hypokalemic acidosis is a normal anion gap metabolic acidosis that has various direct and associated symptoms. Symptoms are associated with hypokalemia instead of hyperkalemia.
Glycogen-storage disease type 0 is most commonly diagnosed during infancy and early childhood.
Screening for ketonuria is done frequently for acutely ill patients, presurgical patients, and pregnant women. Any diabetic patient who has elevated levels of blood and urine glucose should be tested for urinary ketones. In addition, when diabetic treatment is being switched from insulin to oral hypoglycemic agents, the patient's urine should be monitored for ketonuria. The development of ketonuria within 24 hours after insulin withdrawal usually indicates a poor response to the oral hypoglycemic agents. Diabetic patients should have their urine tested regularly for glucose and ketones, particularly when acute infection or other illness develops.
In conditions associated with acidosis, urinary ketones are tested to assess the severity of acidosis and to monitor treatment response. Urine ketones appear before there is any significant increase in blood ketones; therefore, urine ketone measurement is especially helpful in emergency situations.
Three common causes of ketoacidosis are alcohol, starvation, and diabetes, resulting in alcoholic ketoacidosis, starvation ketoacidosis, and diabetic ketoacidosis respectively.
In diabetic ketoacidosis, a high concentration of ketone bodies is usually accompanied by insulin deficiency, hyperglycemia, and dehydration. Particularly in type 1 diabetics the lack of insulin in the bloodstream prevents glucose absorption, thereby inhibiting the production of oxaloacetate through reduced levels of pyruvate, and can cause unchecked ketone body production (through fatty acid metabolism) potentially leading to dangerous glucose and ketone levels in the blood. Hyperglycemia results in glucose overloading the kidneys and spilling into the urine (transport maximum for glucose is exceeded). Dehydration results following the osmotic movement of water into urine (Osmotic diuresis), exacerbating the acidosis.
In alcoholic ketoacidosis, alcohol causes dehydration and blocks the first step of gluconeogenesis by depleting oxaloacetate. The body is unable to synthesize enough glucose to meet its needs, thus creating an energy crisis resulting in fatty acid metabolism, and ketone body formation.
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.