Hyperreflexia, and Progressive neurologic deterioration

ABri amyloidosis is a rare, neurodegenerative disease characterized by progressive cognitive impairment, spastic tetraparesis, and cerebellar ataxia resulting from amyloid deposits in the brain. Spasticity with increased deep tendon reflexes and tone are early symptoms, muscular rigidity evolves later. Progressive mental deterioration usually starts with apathy and impaired memory with progression to complete disorientation.

ABRI AMYLOIDOSIS Is also known as presenile dementia with spastic ataxia|fbd|cerebral amyloid angiopathy, british type|familial dementia, british type|dementia, familial british

• Ataxia
• Spasticity
• Hyperreflexia
• Tremor
• Hypertonia

SOURCES: MESH ORPHANET OMIM MENDELIAN

MMDS5 is an autosomal recessive disorder characterized mainly by progressive neurologic deterioration beginning in early infancy. Affected individuals have essentially no psychomotor development and have early-onset seizures with neurologic decline and spasticity. Brain imaging shows severe leukodystrophy with evidence of dys- or delayed myelination. Death usually occurs in early childhood (summary by Shukla et al., 2017).For a general description and a discussion of genetic heterogeneity of multiple mitochondrial dysfunctions syndrome, see MMDS1 (OMIM ).

• Seizures
• Global developmental delay
• Spasticity
• Feeding difficulties
• Hyperreflexia

SOURCES: OMIM MENDELIAN

Rapid-onset dystonia-parkinsonism (RDP) is a very rare movement disorder, characterized by the abrupt onset of parkinsonism and dystonia, often triggered by physical or psychological stress.

RAPID-ONSET DYSTONIA-PARKINSONISM Is also known as dyt12|dystonia-parkinsonism, rapid-onset|rdp|dystonia 12

• Intellectual disability
• Seizures
• Generalized hypotonia
• Ataxia
• Motor delay

SOURCES: ORPHANET OMIM MESH MENDELIAN

Hereditary diffuse leukoencephalopathy with axonal spheroids and pigmented glia is a rare autosomal dominant disease characterized by a complex phenotype including progressive dementia, apraxia, apathy, impaired balance, parkinsonism, spasticity and epilepsy.

HEREDITARY DIFFUSE LEUKOENCEPHALOPATHY WITH AXONAL SPHEROIDS AND PIGMENTED GLIA Is also known as dementia, familial, neumann type|adult-onset leukoencephalopathy with axonal spheroids and pigmented glia|fpsg|familial progressive subcortical gliosis|leukoencephalopathy with neuroaxonal spheroids, autosomal dominant|pold|alsp|pigmentary orthochromatic

• Seizures
• Ataxia
• Spasticity
• Cognitive impairment
• Hyperreflexia

SOURCES: MESH ORPHANET OMIM MENDELIAN

This disease is characterised by progressive cerebellar ataxia with pyramidal and spinal cord dysfunction, associated with distinctive MRI anomalies and increased lactate in the abnormal white matter.

LEUKOENCEPHALOPATHY WITH BRAIN STEM AND SPINAL CORD INVOLVEMENT-HIGH LACTATE SYNDROME Is also known as mitochondrial aspartyl-trna synthetase deficiency|leukoencephalopathy with brain stem and spinal cord involvement-lactate elevation syndrome|lbsl

• Intellectual disability
• Seizures
• Generalized hypotonia
• Ataxia
• Nystagmus

SOURCES: MESH OMIM ORPHANET MENDELIAN

Tetrahydrobiopterin (BH4)-deficient hyperphenylalaninemia (HPA) comprises a genetically heterogeneous group of progressive neurologic disorders caused by autosomal recessive mutations in the genes encoding enzymes involved in the synthesis or regeneration of BH4. BH4 is a cofactor for phenylalanine hydroxylase (PAH ), tyrosine hydroxylase (TH ) and tryptophan hydroxylase (TPH1 ), the latter 2 of which are involved in neurotransmitter synthesis. The BH4-deficient HPAs are characterized phenotypically by hyperphenylalaninemia, depletion of the neurotransmitters dopamine and serotonin, and progressive cognitive and motor deficits (Dudesek et al., 2001).HPABH4A, caused by mutations in the PTS gene, represents the most common cause of BH4-deficient hyperphenylalaninemia (Dudesek et al., 2001). Other forms of BH4-deficient HPA include HPABH4B (OMIM ), caused by mutation in the GCH1 gene (OMIM ), HPABH4C (OMIM ), caused by mutation in the QDPR gene (OMIM ), and HPABH4D (OMIM ), caused by mutation in the PCBD1 gene (OMIM ). Niederwieser et al. (1982) noted that about 1 to 3% of patients with hyperphenylalaninemia have one of these BH4-deficient forms. These disorders are clinically and genetically distinct from classic phenylketonuria (PKU ), caused by mutation in the PAH gene.Two additional disorders associated with BH4 deficiency and neurologic symptoms do not have overt hyperphenylalaninemia as a feature: dopa-responsive dystonia (OMIM ), caused by mutation in the SPR gene (OMIM ), and autosomal dominant dopa-responsive dystonia (DYT5 ), caused by mutation in the GCH1 gene. Patients with these disorders may develop hyperphenylalaninemia when stressed.

HYPERPHENYLALANINEMIA, BH4-DEFICIENT, A; HPABH4A Is also known as hyperphenylalaninemia, tetrahydrobiopterin-deficient, due to pts deficiency|6-pyruvoyl-tetrahydropterin synthase deficiency|pts deficiency

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

SOURCES: OMIM MENDELIAN

• Seizures
• Generalized hypotonia
• Microcephaly
• Spasticity
• Hyperreflexia

SOURCES: OMIM MENDELIAN

HYPERPHENYLALANINEMIA, BH4-DEFICIENT, B; HPABH4B Is also known as gtp cyclohydrolase i deficiency|hyperphenylalaninemia, tetrahydrobiopterin-deficient, due to gtp cyclohydrolase i deficiency

• Intellectual disability
• Seizures
• Global developmental delay
• Generalized hypotonia
• Strabismus

SOURCES: OMIM MENDELIAN

• Global developmental delay
• Microcephaly
• Nystagmus
• Spasticity
• Tremor

SOURCES: OMIM MENDELIAN

Mitochondrial complex III deficiency, nuclear type 8, is an autosomal recessive disorder characterized by progressive neurodegeneration with onset in childhood. Affected individuals may have normal or delayed early development, and often have episodic acute neurologic decompensation and regression associated with febrile illnesses. The developmental regression results in variable intellectual disability and motor deficits, such as hypotonia, axial hypertonia, and spasticity; some patients may lose the ability to walk independently. Laboratory studies show increased serum lactate and isolated deficiency of mitochondrial complex III in skeletal muscle and fibroblasts. Brain imaging shows a characteristic pattern of multifocal small cystic lesions in the periventricular and deep cerebral white matter (summary by Dallabona et al., 2016).For a discussion of genetic heterogeneity of mitochondrial complex III deficiency, see MC3DN1 (OMIM ).

• Intellectual disability
• Global developmental delay
• Generalized hypotonia
• Ataxia
• Nystagmus

SOURCES: OMIM MENDELIAN