- Diarrhea (HP:0002014): Abnormally increased frequency (usually defined as three or more) loose or watery bowel movements a day. Evidence: PCS. Frequency: 1/1. (PMID:11479731)
- Encephalopathy (HP:0001298): Encephalopathy is a term that means brain disease, damage, or malfunction. In general, encephalopathy is manifested by an altered mental state. Evidence: PCS. Frequency: 9/10. (PMID:33045405)
- Hepatic steatosis (HP:0001397): Steatosis is a term used to denote lipid accumulation within hepatocytes. Evidence: PCS. Frequency: 4/5. (PMID:33045405)
- Elevated circulating aspartate aminotransferase concentration (HP:0031956): The concentration of aspartate aminotransferase (AST) in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:11479731)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 1/29. (PMID:33045405)
- Vomiting (HP:0002013): Forceful ejection of the contents of the stomach through the mouth by means of a series of involuntary spasmic contractions. Evidence: PCS. Frequency: 1/1. (PMID:11479731)
- Seizure (HP:0001250): A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Evidence: PCS. Frequency: 13/14. (PMID:33045405)
- Hepatomegaly (HP:0002240): Abnormally increased size of the liver. Evidence: PCS. Frequency: 15/18. (PMID:33045405)
- Increased circulating free fatty acid level (HP:0030781): A higher than normal levels of the fatty acids which can occur in plasma as a result of lipolysis in adipose tissue or when plasma triacyglycerols are taken into tissues. Evidence: PCS. Frequency: 13/13. (PMID:33045405)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 15/29. (PMID:33045405)
- Steatorrhea (HP:0002570): Greater than normal amounts of fat in the feces. This is a result of malabsorption of lipids in the small intestine and results in frothy foul-smelling fecal matter that floats. Evidence: PCS. Frequency: 1/2. (PMID:33045405)
- Elevated circulating alanine aminotransferase concentration (HP:0031964): An abnormally high concentration in the circulation of alanine aminotransferase (ALT). Evidence: PCS. Frequency: 1/1. (PMID:11479731)
- Ketonuria (HP:0002919): High levels of ketone bodies (acetoacetic acid, beta-hydroxybutyric acid, and acetone) in the urine. Ketone bodies are insignificant in the blood and urine of normal individuals in the postprandial or overnight-fasted state. Evidence: PCS. Frequency: 7/11. (PMID:33045405)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 13/29. (PMID:33045405)
- Elevated urinary 3-hydroxybutyric acid (HP:0040155): An increased amount of 3-hydroxybutyric acid in the urine. Evidence: PCS. Frequency: 6/7. (PMID:33045405)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:11228257)
- Hypoglycemia (HP:0001943): A decreased concentration of glucose in the blood. Evidence: PCS. Frequency: 25/28. (PMID:33045405)
- Increased circulating lactate dehydrogenase concentration (HP:0025435): An elevated level of the enzyme lactate dehydrogenase in the blood circulation. Evidence: PCS. Frequency: 1/1. (PMID:11479731)
- Elevated circulating hepatic transaminase concentration (HP:0002910): Elevations of the levels of SGOT and SGPT in the serum. SGOT (serum glutamic oxaloacetic transaminase) and SGPT (serum glutamic pyruvic transaminase) are transaminases primarily found in the liver and heart and are released into the bloodstream as the result of liver or heart damage. SGOT and SGPT are used clinically mainly as markers of liver damage. Evidence: PCS. Frequency: 13/16. (PMID:33045405)
- Dicarboxylic aciduria (HP:0003215): An increased concentration of dicarboxylic acid in the urine. Evidence: PCS. Frequency: 21/22. (PMID:33045405)
- Hypophosphatemia (HP:0002148): The concentration of phosphate ion in the blood circulation is below the lower limit of normal. Evidence: PCS. Frequency: 3/3. (PMID:33045405)
- Metabolic acidosis (HP:0001942): Metabolic acidosis (MA) is characterized by a fall in blood pH due to a reduction of serum bicarbonate concentration. This can occur as a result of either the accumulation of acids (high anion gap MA) or the loss of bicarbonate from the gastrointestinal tract or the kidney (hyperchloremic MA). By definition, MA is not due to a respirary cause. Evidence: PCS. Frequency: 20/22. (PMID:33045405)
- Coma (HP:0001259): The complete absence of wakefulness and consciousness, which is evident through a lack of response to any form of external stimuli. Evidence: PCS. Frequency: 16/20. (PMID:33045405)
- Hypoglycemic coma (HP:0001325): Coma induced by low blood sugar. Evidence: PCS. Frequency: 1/1. (PMID:11479731)
These phenotypes are associated with the disease 3-hydroxy-3-methylglutaryl-CoA synthase deficiency (OMIM:605911).