Phenotypes associated with the disease congenital myasthenic syndrome 10 (OMIM:254300):
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. (PMID:16917026)
- Easy fatigability (HP:0003388): Increased susceptibility to fatigue. Evidence: IEA. (OMIM:254300)
- Fatigable weakness (HP:0003473): A type of weakness that occurs after a muscle group is used and lessens if the muscle group has some rest. That is, there is diminution of strength with repetitive muscle actions. Evidence: PCS. (PMID:16917026)
- Distal amyotrophy (HP:0003693): Muscular atrophy affecting muscles in the distal portions of the extremities. Evidence: IEA. (OMIM:254300)
- Bulbar palsy (HP:0001283): Bulbar weakness (or bulbar palsy) refers to bilateral impairment of function of the lower cranial nerves IX, X, XI and XII, which occurs due to lower motor neuron lesion either at nuclear or fascicular level in the medulla or from bilateral lesions of the lower cranial nerves outside the brain-stem. Bulbar weakness is often associated with difficulty in chewing, weakness of the facial muscles, dysarthria, palatal weakness and regurgitation of fluids, dysphagia, and dysphonia. Evidence: IEA. (OMIM:254300)
- Reduced vital capacity (HP:0002792): An abnormal reduction on the vital capacity, which is defined as the total lung capacity (volume of air in the lungs at maximal inflation) less the residual volume (i.e., volume of air in the lungs following maximal exhalation) of the lung. Evidence: PCS. Frequency: 4/10. (PMID:16917026)
- Muscle spasm (HP:0003394): Sudden and involuntary contractions of one or more muscles. Evidence: IEA. (OMIM:254300)
- Gowers sign (HP:0003391): A phenomenon whereby patients are not able to stand up without the use of the hands owing to weakness of the proximal muscles of the lower limbs. Evidence: IEA. (OMIM:254300)
- Weakness of facial musculature (HP:0030319): Reduced strength of one or more muscles innervated by the facial nerve (the seventh cranial nerve). Evidence: PCS. Frequency: 19/19. (PMID:16917026)
- Anti-neuromuscular Junction acetylcholine receptor antibody positivity (HP:0030208): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against neuromuscular junction acetylcholine receptors. Evidence: PCS. Frequency: 0/19. (PMID:16917026)
- Mildly elevated creatine kinase (HP:0008180). Evidence: IEA. (OMIM:254300)
- Tongue atrophy (HP:0012473): Wasting of the tongue. Evidence: PCS. Frequency: 4/10. (PMID:16917026)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. (PMID:16917026)
- Ptosis (HP:0000508): The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective). Evidence: PCS. Frequency: 13/19. (PMID:16917026)
- Decreased fetal movement (HP:0001558): An abnormal reduction in quantity or strength of fetal movements. Evidence: IEA. Frequency: Occasional (HP:0040283). (OMIM:254300)
- 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: IEA. (OMIM:254300)
- Waddling gait (HP:0002515): Weakness of the hip girdle and upper thigh muscles, for instance in myopathies, leads to an instability of the pelvis on standing and walking. If the muscles extending the hip joint are affected, the posture in that joint becomes flexed and lumbar lordosis increases. The patients usually have difficulties standing up from a sitting position. Due to weakness in the gluteus medius muscle, the hip on the side of the swinging leg drops with each step (referred to as Trendelenburg sign). The gait appears waddling. The patients frequently attempt to counteract the dropping of the hip on the swinging side by bending the trunk towards the side which is in the stance phase (in the German language literature this is referred to as Duchenne sign). Similar gait patterns can be caused by orthopedic conditions when the origin and the insertion site of the gluteus medius muscle are closer to each other than normal, for instance due to a posttraumatic elevation of the trochanter or pseudarthrosis of the femoral neck. Evidence: IEA. (OMIM:254300)
- Respiratory insufficiency due to muscle weakness (HP:0002747). Evidence: IEA. (OMIM:254300)
- Proximal amyotrophy (HP:0007126): Amyotrophy (muscular atrophy) affecting the proximal musculature. Evidence: TAS. (OMIM:254300)
- Axial muscle weakness (HP:0003327): Reduced strength of the axial musculature (i.e., of the muscles of the head and neck, spine, and ribs). Evidence: PCS. Frequency: 16/18. (PMID:16917026)
- Ophthalmoparesis (HP:0000597): Ophthalmoplegia is a paralysis or weakness of one or more of the muscles that control eye movement. Evidence: IEA. Frequency: Occasional (HP:0040283). (OMIM:254300)