Global developmental delay, and Left ventricular hypertrophy

Childhood encephalopathy due to thiamine pyrophosphokinase deficiency is a rare inborn error of metabolism disorder characterized by early-onset, acute, encephalopathic episodes (frequently triggered by viral infections), associated with lactic acidosis and alpha-ketoglutaric aciduria, which typically manifest with variable degrees of ataxia, generalized developmental regression (which deteriorates with each episode) and dystonia. Other manifestations include spasticity, seizures, truncal hypotonia, limb hypertonia, brisk tendon reflexes and reversible coma.

CHILDHOOD ENCEPHALOPATHY DUE TO THIAMINE PYROPHOSPHOKINASE DEFICIENCY Is also known as encephalopathy, episodic, due to thiamine pyrophosphokinase deficiency

• Seizures
• Global developmental delay
• Generalized hypotonia
• Microcephaly
• Ataxia

SOURCES: OMIM ORPHANET MENDELIAN

Hypomyelinating leukodystrophy-13 is an autosomal recessive neurodegenerative disorder characterized by infantile onset of delayed psychomotor development, axial hypotonia, and spasticity associated with delayed myelination and periventricular white matter abnormalities on brain imaging. More variable neurologic deficits, such as visual impairment, may also occur. Some patients may experience cardiac failure during acute illness (summary by Edvardson et al., 2016).For a general phenotypic description and a discussion of genetic heterogeneity of HLD, see {312080}.

C11ORF73-RELATED AUTOSOMAL RECESSIVE HYPOMYELINATING LEUKODYSTROPHY Is also known as c11orf73-related autosomal recessive hypomyelinating leukoencephalopathy|hypomyelinating leukodystrophy due to hikeshi deficiency

• Global developmental delay
• Generalized hypotonia
• Ataxia
• Nystagmus
• Failure to thrive

SOURCES: ORPHANET OMIM MENDELIAN

X-linked myopathy with excessive autophagy (XMEA) is an X-linked recessive skeletal muscle disorder characterized by childhood onset of progressive muscle weakness and atrophy primarily affecting the proximal muscles. While onset is usually in childhood, it can range from infancy to adulthood. Many patients lose ambulation and become wheelchair-bound. Other organ systems, including the heart, are clinically unaffected. Muscle biopsy shows intracytoplasmic autophagic vacuoles with sarcolemmal features and a multilayered basal membrane (summary by Ramachandran et al., 2013; Kurashige et al., 2013, and Ruggieri et al., 2015).Danon disease (OMIM ), caused by mutation in the LAMP2 gene (OMIM ) on chromosome Xq24, is a distinct disorder with similar pathologic features.

MYOPATHY, X-LINKED, WITH EXCESSIVE AUTOPHAGY; MEAX Is also known as xmea

• Global developmental delay
• Generalized hypotonia
• Scoliosis
• Muscle weakness
• Flexion contracture

SOURCES: OMIM MENDELIAN

Congenital muscular dystrophy-dystroglycanopathy with brain and eye anomalies (type A), which includes both the more severe Walker-Warburg syndrome (WWS) and the slightly less severe muscle-eye-brain disease (MEB), is an autosomal recessive disorder with characteristic brain and eye malformations, profound mental retardation, congenital muscular dystrophy, and death usually in the first years of life. It represents the most severe end of a phenotypic spectrum of similar disorders resulting from defective glycosylation of DAG1 (OMIM ), collectively known as 'dystroglycanopathies' (Beltran-Valero de Bernabe et al., 2004).For a general phenotypic description and a discussion of genetic heterogeneity of muscular dystrophy-dystroglycanopathy type A, see MDDGA1 (OMIM ).

MUSCULAR DYSTROPHY-DYSTROGLYCANOPATHY (CONGENITAL WITH BRAIN AND EYE ANOMALIES), TYPE A, 5; MDDGA5 Is also known as walker-warburg syndrome or muscle-eye-brain disease, fkrp-related

• Intellectual disability
• Global developmental delay
• Generalized hypotonia
• Cataract
• Feeding difficulties

SOURCES: OMIM MENDELIAN

Glycogen storage disease due to acid maltase deficiency, infantile onset is the most severe form of glycogen storage disease due to acid maltase deficiency, characterized by cardiomegaly with respiratory distress, muscle weakness and feeding difficulties. It is often fatal.

GLYCOGEN STORAGE DISEASE DUE TO ACID MALTASE DEFICIENCY, INFANTILE ONSET Is also known as glycogenosis due to acid maltase deficiency, infantile onset|glycogen storage disease type ii, infantile onset|gsd type 2, infantile onset|alpha-1,4-glucosidase acid deficiency, infantile onset|gsd type ii, infantile onset|glycogenosis type ii, infantile

• Global developmental delay
• Failure to thrive
• Muscular hypotonia
• Cognitive impairment
• Feeding difficulties

SOURCES: ORPHANET MENDELIAN

Encephalopathy-hypertrophic cardiomyopathy-renal tubular disease syndrome is a rare mitochondrial disease due to a defect in coenzyme Q10 biosynthesis that manifests with a broad spectrum of signs and symptoms which may include: neonatal lactic acidosis, global developmental delay, tonus disorder, seizures, reduced spontaneous movements, ventricular hypertrophy, bradycardia, renal tubular dysfunction with massive lactic acid excretion in urine, severe biochemical defect of respiratory chain complexes II/III when assayed together and deficiency of coenzyme Q10 in skeletal muscle. Cerebral and cerebellar atrophy can be seen on magnetic resonance imaging and multiple choroid plexus cysts and symmetrical hyperechoic signal alterations in basal ganglia have been observed on ultrasound.

• Seizures
• Global developmental delay
• Generalized hypotonia
• Feeding difficulties
• Hyperreflexia

SOURCES: ORPHANET OMIM MENDELIAN

• Intellectual disability
• Seizures
• Global developmental delay
• Spasticity
• Hypertension

SOURCES: OMIM ORPHANET MENDELIAN

Glycogen storage disease due to LAMP-2 (Lysosomal-Associated Membrane Protein 2) deficiency is a lysosomal glycogen storage disease characterised by severe cardiomyopathy and variable degrees of muscle weakness, frequently associated with intellectual deficit.

GLYCOGEN STORAGE DISEASE DUE TO LAMP-2 DEFICIENCY Is also known as vacuolar cardiomyopathy and myopathy, x-linked|antopol disease|gsd due to lamp-2 deficiency|lysosomal glycogen storage disease without acid maltase deficiency, formerly|glycogenosis due to lamp-2 deficiency|gsd2b, formerly|gsd iib, formerly|glycogen stora

• Intellectual disability
• Global developmental delay
• Muscle weakness
• Pain
• Cognitive impairment

SOURCES: MESH ORPHANET OMIM MENDELIAN

MDDGB2 is an autosomal recessive congenital muscular dystrophy associated with mental retardation and mild structural brain abnormalities (Yanagisawa et al., 2007). It is part of a group of similar disorders, collectively known as 'dystroglycanopathies,' resulting from defective glycosylation of alpha-dystroglycan (DAG1 ) (Godfrey et al., 2007).For a discussion of genetic heterogeneity of congenital muscular dystrophy-dystroglycanopathy type B, see MDDGB1 (OMIM ).

MUSCULAR DYSTROPHY-DYSTROGLYCANOPATHY (CONGENITAL WITH MENTAL RETARDATION), TYPE B, 2; MDDGB2 Is also known as muscular dystrophy, congenital, pomt2-related

• Intellectual disability
• Global developmental delay
• Generalized hypotonia
• Microcephaly
• Scoliosis

SOURCES: OMIM MENDELIAN

Lethal polymalformative syndrome, Boissel type is a rare, genetic, lethal, multiple congenital anomalies/dysmorphic syndrome characterized by failure to thrive, severe developmental delay, severe postanatal microcephaly, frequent congenital cardiac defects and characteristic facial dysmorphysm (including coarse face with anteverted nostrils, thin vermillion, prominent alveolar ridge and retro- or micrognatia). Additional common features include neurologic abnormalities (hyper-/hypotonia, sensorineural deafness, hydrocephalus, cerebral atrophy, seizures), as well as brachydactyly, cutis marmorata and genital anomalies.

• Seizures
• Global developmental delay
• Hearing impairment
• Microcephaly
• Growth delay

SOURCES: MESH ORPHANET OMIM MENDELIAN