- Progressive neurologic deterioration (HP:0002344). Evidence: IEA. (OMIM:252920)
- Hearing impairment (HP:0000365): A decreased magnitude of the sensory perception of sound. Evidence: IEA. (OMIM:252920)
- 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: IEA. (OMIM:252920)
- Asymmetric septal hypertrophy (HP:0001670): Hypertrophic cardiomyopathy with an asymmetrical pattern of hypertrophy, with a predilection for the interventricular septum and myocyte disarray. Evidence: IEA. (OMIM:252920)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: IEA. (OMIM:252920)
- Hepatomegaly (HP:0002240): Abnormally increased size of the liver. Evidence: IEA. (OMIM:252920)
- Coarse facial features (HP:0000280): Absence of fine and sharp appearance of brows, nose, lips, mouth, and chin, usually because of rounded and heavy features or thickened skin with or without thickening of subcutaneous and bony tissues. Evidence: IEA. (OMIM:252920)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 8/16. (PMID:11153910)
- Aggressive behavior (HP:0000718): Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires). Evidence: IEA. (OMIM:252920)
- Ovoid thoracolumbar vertebrae (HP:0003309). Evidence: IEA. (OMIM:252920)
- Hyperactivity (HP:0000752): Hyperactivity is a condition characterized by constant and unusually high levels of activity, even in situations where it is deemed inappropriate. Evidence: IEA. (OMIM:252920)
- Heparan sulfate excretion in urine (HP:0002159): An increased concentration of heparan sulfates in the urine. Evidence: IEA. (OMIM:252920)
- Hirsutism (HP:0001007): Abnormally increased hair growth referring to a male pattern of body hair (androgenic hair). Evidence: IEA. (OMIM:252920)
- Intellectual disability (HP:0001249): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: PCS. Frequency: 16/16. (PMID:11153910)
- Splenomegaly (HP:0001744): Abnormal increased size of the spleen. Evidence: IEA. (OMIM:252920)
- Diarrhea (HP:0002014): Abnormally increased frequency (usually defined as three or more) loose or watery bowel movements a day. Evidence: IEA. (OMIM:252920)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 8/16. (PMID:11153910)
- Reduced tissue alpha-N-acetylglucosaminidase activity (HP:6000360): Concentration or activity of alpha-N-acetylglucosaminidase (EC 3.2.1.50) below the lower limit of normal. This enzyme can be measured in multiple tissues including leukocytes and cultured fibroblasts. It is also known as alpha-acetylglucosaminidase, N-acetyl-alpha-D-glucosaminidase, N-acetyl-alpha-glucosaminidase, and alpha-D-2-acetamido-2-deoxyglucosidase. Evidence: PCS. Frequency: 7/7. (PMID:12202988)
- Cardiomegaly (HP:0001640): Increased size of the heart, clinically defined as an increased transverse diameter of the cardiac silhouette that is greater than or equal to 50% of the transverse diameter of the chest (increased cardiothoracic ratio) on a posterior-anterior projection of a chest radiograph or a computed tomography. Evidence: IEA. (OMIM:252920)
- Joint stiffness (HP:0001387): Joint stiffness is a perceived sensation of tightness in a joint or joints when attempting to move them after a period of inactivity. Joint stiffness typically subsides over time. Evidence: TAS. (OMIM:252920)
- Dense calvaria (HP:0000250): An abnormal increase of density of the bones making up the calvaria. Evidence: IEA. (OMIM:252920)
- Dysostosis multiplex (HP:0000943). Evidence: PCS. Frequency: 16/16. (PMID:11153910)
- 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:11153910)
- Coarse hair (HP:0002208): Hair shafts are rough in texture. Evidence: IEA. (OMIM:252920)
- Thickened ribs (HP:0000900): Increased thickness (diameter) of ribs. Evidence: IEA. (OMIM:252920)
- Recurrent upper respiratory tract infections (HP:0002788): An increased susceptibility to upper respiratory tract infections as manifested by a history of recurrent upper respiratory tract infections (running ears - otitis, sinusitis, pharyngitis, tonsillitis). Evidence: IEA. (OMIM:252920)
- Synophrys (HP:0000664): Meeting of the medial eyebrows in the midline. Evidence: IEA. (OMIM:252920)
These phenotypes are associated with the disease mucopolysaccharidosis type 3B (OMIM:252920).