Global developmental delay, and Hepatomegaly

Pyridoxine-dependent epilepsy (PDE) is a rare neurometabolic disease characterized by recurrent intractable seizures in the prenatal, neonatal and postnatal period that are resistant to anti-epileptic drugs (AEDs) but that are responsive to pharmacological dosages of pyridoxine (vitamin B6).

PYRIDOXINE-DEPENDENT EPILEPSY Is also known as antiquitin deficiency|vitamin b6-dependent seizures

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

SOURCES: ORPHANET MENDELIAN

Vitamin B12-unresponsive methylmalonic acidemia type mut0 is an inborn error of metabolism characterized by recurrent ketoacidotic comas or transient vomiting, dehydration, hypotonia and intellectual deficit, which does not respond to administration of vitamin B12.

VITAMIN B12-UNRESPONSIVE METHYLMALONIC ACIDEMIA TYPE MUT0 Is also known as complete deficiency of methylmalonyl-coa mutase|vitamin b12-unresponsive methylmalonic aciduria type mut0

• Intellectual disability
• Global developmental delay
• Growth delay
• Muscular hypotonia
• Anemia

SOURCES: ORPHANET MENDELIAN

GLYCOGEN STORAGE DISEASE VI; GSD6 Is also known as phosphorylase deficiency glycogen-storage disease of liver|hers disease|gsd vi

• Intellectual disability
• Global developmental delay
• Short stature
• Growth delay
• Failure to thrive

SOURCES: OMIM MENDELIAN

Glycogen storage disease type IX is a metabolic disorder resulting from a deficiency of hepatic phosphorylase kinase, a hexadecameric enzyme comprising 4 copies each of 4 unique subunits encoded by 4 different genes: alpha (PHKA2), beta (PHKB ), gamma (PHKG2 ), and delta (CALM1 ). Mutations within the PHKA2, PHKB, and PHKG2 genes result in GSD9A, GSD9B (OMIM ), and GSD9C (OMIM ), respectively. GSD IXa is an X-linked recessive disorder, whereas the others are autosomal recessive.GSD IXa has been further divided into types IXa1 (GSD9A1), with no PHK activity in liver or erythrocytes, and IXa2 (GSD9A2), with no PHK in liver, but normal activity in erythrocytes. The clinical presentation of both subtypes is the same, and both are caused by mutations in the PHKA2 gene. However, mutations that result in IXa2 are either missense or small in-frame deletions or insertions enabling residual enzyme expression in erythrocytes (Keating et al., 1985; Hendrickx et al., 1994; Beauchamp et al., 2007).See also X-linked muscle PHK deficiency (GSD9D ), caused by mutation in the gene encoding the muscle-specific alpha PHK subunit (PHKA1 ).

GLYCOGEN STORAGE DISEASE IXA1; GSD9A1 Is also known as glycogen storage disease viii, formerly|gsd8, formerly|gsd viii, formerly|liver glycogenosis, x-linked, type i|xlg1

• Intellectual disability
• Global developmental delay
• Short stature
• Growth delay
• Failure to thrive

SOURCES: OMIM MENDELIAN

Alpha-N-acetylgalactosaminidase (NAGA) deficiency type 3 is a rare clinically heterogeneous type of NAGA deficiency (see this term) with developmental, neurologic and psychiatric manifestations presenting at an intermediate age.

ALPHA-N-ACETYLGALACTOSAMINIDASE DEFICIENCY TYPE 3 Is also known as naga deficiency type 3|schindler disease type 3

• Intellectual disability
• Seizures
• Global developmental delay
• Strabismus
• Cataract

SOURCES: ORPHANET MENDELIAN

Combined oxidative phosphorylation defect type 9 is a rare mitochondrial disease due to a defect in mitochondrial protein synthesis characterized by initially normal growth and development followed by the infantile-onset of failure to thrive, psychomotor delay, poor feeding, dyspnea, severe hypertrophic cardiomyopathy and hepatomegaly. Laboratory studies report increased plasma lactate and alanine, abnormal liver enzymes and decreased activity of mitochondrial respiratory chain complexes I, III, IV, and V.

COMBINED OXIDATIVE PHOSPHORYLATION DEFECT TYPE 9 Is also known as coxpd9

• Global developmental delay
• Failure to thrive
• Feeding difficulties
• Hepatomegaly
• Cardiomyopathy

SOURCES: ORPHANET OMIM MENDELIAN

• Intellectual disability
• Global developmental delay
• Ataxia
• Delayed speech and language development
• Hepatomegaly

SOURCES: OMIM MENDELIAN

Hemophagocytic lymphohistiocytosis is a hyperinflammatory disorder clinically diagnosed based on the fulfillment of 5 of 8 criteria, including fever, splenomegaly, bicytopenia, hypertriglyceridemia and/or hypofibrinogenemia, hemophagocytosis, low or absent natural killer (NK) cell activity, hyperferritinemia, and high soluble IL2 receptor levels (IL2R ). The disorder typically presents in infancy or early childhood. Persistent remission is rarely achieved with chemo- or immunotherapy; hematopoietic stem cell transplantation is the only cure (summary by Muller et al., 2014).For a phenotypic description and a discussion of genetic heterogeneity of familial hemophagocytic lymphohistiocytosis (FHL), see {267700}.

HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS, FAMILIAL, 4; FHL4 Is also known as hlh4|hplh4

• Seizures
• Global developmental delay
• Generalized hypotonia
• Anemia
• Hepatomegaly

SOURCES: OMIM MENDELIAN

Wolman disease represents the most severe manifestation of lysosomal acid lipase deficiency. Milder phenotypes as a whole are referred to as cholesterol ester storage disease (see this term). The acid lipase enzyme plays an essential role in lysosomal hydrolysis of both esterified cholesterol and triglycerides of lipoproteic origin. In Wolman disease, the rarest form of acid lipase deficiency, these lipids accumulate in most tissues.

• Global developmental delay
• Growth delay
• Anemia
• Hepatomegaly
• Fever

SOURCES: ORPHANET MENDELIAN

ALG2-CDG is a form of congenital disorders of N-linked glycosylation characterized by iris coloboma, cataract, infantile spasms, developmental delay and abnormal coagulation factors. The disease is caused by loss-of-function mutations in the gene ALG2 (9q31.1). Transmission is autosomal recessive.

ALG2-CDG Is also known as congenital disorder of glycosylation type 1i|cdg ii|cdgii|cdg syndrome type ii|mannosyltransferase 2 deficiency|carbohydrate deficient glycoprotein syndrome type ii|cdg1i|congenital disorder of glycosylation type ii|cdg-ii

• Intellectual disability
• Seizures
• Global developmental delay
• Nystagmus
• Cataract

SOURCES: OMIM ORPHANET MENDELIAN