Symptoms in humans include all those of typical metabolic acidosis (nausea, vomiting, generalized muscle weakness, and laboured and deep breathing). Causes
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
Leigh syndrome
Drugs
Linezolid
Paracetamol/acetaminophen poisoning
Metformin: this risk is low (less than 10 cases for 100,000 patient years), but the risk of metformin-induced lactic acidosis (MALA) increases in certain situations where both the plasma levels of metformin are increased and lactate clearance is impaired. The older related and now withdrawn drug phenformin carried a much higher risk of lactic acidosis. Isoniazid toxicity
Propofol
Epinephrine
Propylene glycol (D-lactic acidosis)
Nucleoside reverse-transcriptase inhibitors
Abacavir/dolutegravir/lamivudine
Emtricitabine/tenofovir
Potassium cyanide (cyanide poisoning)
Fialuridine
Other
Thiamine deficiency (especially during TPN)
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-Hodgkins and Burkitt lymphomas
Pheochromocytoma
Tumor lysis syndrome
D-lactic acidosis due to intestinal bacterial flora production in short gut syndrome

Pathophysiology
Glucose metabolism begins with glycolysis, in which the molecule is broken down into pyruvate in ten enzymatic steps. A significant proportion of pyruvate is converted into lactate (usually 10:1). The human metabolism produces about 20 mmol/kg of lactic acid every 24 hours. This happens predominantly in tissues (especially muscle) that have high levels of the "A" isoform of the enzyme lactate dehydrogenase (LDHA), which predominantly converts pyruvate into lactate.
A cutaneous myxoma, or superficial angiomyxoma, consists of a multilobulated myxoid mass containing stellate or spindled fibroblasts with pools of mucin forming cleft-like spaces. There is often a proliferation of blood vessels and an inflammatory infiltrate. Staining is positive for vimentin, negative for cytokeratin and desmin, and variable for CD34, Factor VIIIa, SMA, MSA and S-100.Clinically, it may present as solitary or multiple flesh-colored nodules on the face, trunk, or extremities. It may occur as part of the Carney complex, and is sometimes the first sign. Local recurrence is common. See also
Myxoma
Skin lesion


== References ==