Phenotypes associated with the disease mitochondrial DNA depletion syndrome 12B (cardiomyopathic type), autosomal recessive (OMIM:615418):
- Achilles tendon contracture (HP:0001771): A contracture of the Achilles tendon. Evidence: PCS. Frequency: 1/1. (PMID:16155110)
- Elevated circulating creatine kinase activity (HP:0003236): The activity of creatine kinase in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:16155110)
- Mild intellectual disability (HP:0001256): Mild intellectual disability (ID) is defined as a type of ID characterized by mildly sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) the range of 50-69. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Cataract (HP:0000518): A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: PCS. Frequency: 1/2. (PMID:25732997;PMID:22187496)
- Headache (HP:0002315): Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve. Evidence: PCS. Frequency: 1/1. (PMID:16155110)
- Cytochrome C oxidase-negative muscle fibers (HP:0003688): An abnormally reduced activity of the enzyme cytochrome C oxidase in muscle tissue. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Nausea and vomiting (HP:0002017): Nausea is a commonly encountered symptom that has been defined as an unpleasant painless subjective feeling that one will imminently vomit. Vomiting has been defined as the forceful expulsion of the contents of the stomach, duodenum, or jejunum through the oral cavity. While nausea and vomiting are often thought to exist on a temporal continuum, this is not always the case. There are situations when severe nausea may be present without emesis and less frequently, when emesis may be present without preceding nausea. Evidence: PCS. Frequency: 1/1. (PMID:16155110)
- Myalgia (HP:0003326): Pain in muscle. Evidence: PCS. Frequency: 1/1. (PMID:16155110)
- Multiple mitochondrial DNA deletions (HP:0003689): The presence of multiple deletions of mitochondrial DNA (mtDNA). Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Hyperalaninemia (HP:0003348): An increased concentration of alanine in the blood. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Exercise intolerance (HP:0003546): A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender. Evidence: PCS. Frequency: 2/2. (PMID:16155110;PMID:25732997)
- Skeletal muscle atrophy (HP:0003202): The presence of skeletal muscular atrophy (which is also known as amyotrophy). Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Ragged-red muscle fibers (HP:0003200): An abnormal appearance of muscle fibers observed on muscle biopsy. Ragged red fibers can be visualized with Gomori trichrome staining as irregular and intensely red subsarcolemmal zones, whereas the normal myofibrils are green. The margins of affect fibers appear red and ragged. The ragged-red is due to the accumulation of abnormal mitochondria below the plasma membrane of the muscle fiber, leading to the appearance of a red rim and speckled sarcoplasm. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Heart murmur (HP:0030148): An extra or unusual sound heard during a heartbeat caused vibrations resulting from the flow of blood through the heart. Evidence: PCS. Frequency: 1/1. (PMID:16155110)
- Easy fatigability (HP:0003388): Increased susceptibility to fatigue. Evidence: PCS. Frequency: 2/2. (PMID:16155110;PMID:22187496)
- Increased circulating lactate concentration (HP:0002151): Abnormally increased level of blood lactate (2-hydroxypropanoic acid). Lactate is produced from pyruvate by lactate dehydrogenase during normal metabolism. The terms lactate and lactic acid are often used interchangeably but lactate (the component measured in blood) is strictly a weak base whereas lactic acid is the corresponding acid. Lactic acidosis is often used clinically to describe elevated lactate but should be reserved for cases where there is a corresponding acidosis (pH below 7.35). Evidence: PCS. Frequency: 2/2. (PMID:16155110;PMID:25732997)
- Dyspnea (HP:0002094): Difficult or labored breathing. Dyspnea is a subjective feeling only the patient can rate, e.g., on a Borg scale. Evidence: PCS. Frequency: 1/1. (PMID:25732997)
- Increased CSF lactate (HP:0002490): Increased concentration of lactate in the cerebrospinal fluid. Evidence: PCS. Frequency: 1/1. (PMID:25732997)
- Fatigue (HP:0012378): A subjective feeling of tiredness characterized by a lack of energy and motivation. Evidence: PCS. Frequency: 1/1. (PMID:25732997)
- Hypertrophic cardiomyopathy (HP:0001639): Hypertrophic cardiomyopathy (HCM) is defined by the presence of increased ventricular wall thickness or mass in the absence of loading conditions (hypertension, valve disease) sufficient to cause the observed abnormality. Evidence: PCS. Frequency: 2/2. (PMID:25732997;PMID:22187496)
- Left ventricular hypertrophy (HP:0001712): Enlargement or increased size of the heart left ventricle. Evidence: PCS. Frequency: 2/2. (PMID:16155110;PMID:22187496)
- 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:16155110)
- Decreased activity of mitochondrial complex IV (HP:0008347): A reduction in the activity of the mitochondrial respiratory chain complex IV, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Severe lactic acidosis (HP:0004900): A severe form of lactic acidemia. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- Slowly progressive (HP:0003677): Applies to a disease manifestation that only slowly increases in scope or severity over the course of time. Evidence: PCS. (PMID:22187496)
- Obesity (HP:0001513): Accumulation of substantial excess body fat. Evidence: PCS. Frequency: 1/1. (PMID:22187496)
- EMG: myopathic abnormalities (HP:0003458): The presence of abnormal electromyographic patterns indicative of myopathy, such as small-short polyphasic motor unit potentials. Evidence: PCS. Frequency: 1/1. (PMID:22187496)