Presentation
Clinical description Patients usually present in early childhood with hepatomegaly, growth retardation, and mild delay in motor development. Fast-induced hypoglycemia and hyperlipidemia are variable and, if present, are generally mild. [orpha.net]
However, the focus of the book remains clinical, describing symptoms and signs at presentation, how to come to a diagnosis and methods for treatment. As with the previous edition, the book can be used in two main ways. [books.google.com]
Immune System
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Splenomegaly
Hepatomegaly is seen in all except: Type 0 (Glycogen synthase deficiency) Type IV or Anderson’s disease (Hepatomegaly may be absent and death is early, i.e. in 2 years due to early cirrhosis) Hepatomegaly with splenomegaly and other generalized signs [epomedicine.com]
Early infancy; rarely, the neonatal period, late childhood, or adulthood (manifesting as a variant nonprogressive or a neuromuscular form) Clinical features: Hepatomegaly with progressive cirrhosis and hypoglycemia, esophageal varices, and ascites; splenomegaly [merckmanuals.com]
Splenomegaly, liver cirrhosis, doll facies, osteoporosis, neurologic disease, elevated serum lactate, metabolic acidosis and renal tubular acidosis have been described very rarely. [wjgnet.com]
Deficiency Cardinal Clinical Features Distinctive Features Type 0 Glycogen synthase Fasting hypoglycemia and ketosis No hepatomegaly; postprandial hyperglycemia and hyperlactatemia Type IA Glucose-6-phosphatase Severe hypoglycemia; hepatomegaly; No splenomegaly [clinicaladvisor.com]
Liver, Gall & Pancreas
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Liver Fibrosis
An increased risk of cirrhosis due to liver fibrosis is observed in cases with autosomal recessive inheritance. [orpha.net]
In contrast, individuals with mutations in the PHKG2 subunit of the PHK enzyme usually have more severe symptoms; PHKG2 gene changes are particularly associated with recurrent hypoglycemia, hepatomegaly and rarely liver fibrosis. [agsdus.org]
PHKG2 deficiency is a more severe disorder with a high preponderance to liver fibrosis. There have been several reports of this morbidity but this seems to stabilise over time with treatment. Long-term outcome data are not available. [tp.amegroups.com]
Musculoskeletal
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Osteopenia
Full-cheeked round face and osteopenia have been reported on exceptional occasions in cases with an X-linked inheritance. An increased risk of cirrhosis due to liver fibrosis is observed in cases with autosomal recessive inheritance. [orpha.net]
Generalized osteopenia develops early and may lead to fractures. Hypophosphatemic rickets and osteoporosis later in life are constant features. [wjgnet.com]
Motor developmental delay can occur in GSD IIIa and both forms can be associated with osteopenia. [tp.amegroups.com]
Anterior pelvic tilt; Forward trunk lean Relatively spared muscles Hip flexors Spinal extensors Skeletal Contractures Hip flexors Iliotibial bands Plantar flexors: Foot Posterior tibial Plantar fascia Scoliosis: Less than untreated patients Bone issues: Osteopenia [neuromuscular.wustl.edu]
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Muscle Hypotonia
Clinical features are muscle hypotonia and cirrhosis. Death from liver disease usually occurs before age 2. [icd10data.com]
hypotonia, hypercholesterolemia Treatment: Nonspecific Type VIII/IXa: X-linked phosphorylase kinase PHKA2 (Xp22)* Type IXb Liver and muscle phosphorylase kinase PHKB (16q12-q13)* Type IXc Liver phosphorylase kinase PHKG2 (16p12.1-p11.2)* Type IXd Muscle [merckmanuals.com]
Face, Head & Neck
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Round Face
Full-cheeked round face and osteopenia have been reported on exceptional occasions in cases with an X-linked inheritance. An increased risk of cirrhosis due to liver fibrosis is observed in cases with autosomal recessive inheritance. [orpha.net]
Neurologic
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Excitement
The meeting was closed by two exciting lectures, given by Dr J. R. Hobbs, London, and Dr F. Ledley, Houston, on the outcome of bone marrow transplantation and on future aspects of gene therapy in patients with inborn errors of metabolism. [books.google.com]
Workup
His age at first diagnostic workup was 4 years. Of note, most mutations in Korean GSD IX patients were deletion or splicing mutations, except for one known missense mutation of c.884G A (p.Arg295His) [ 8 ]. [bmcmedgenet.biomedcentral.com]
Serum
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Fasting Hypoglycemia
[…] distention, hepatomegaly, renomegaly, mild fasting hypoglycemia and hyperlipidemia, glucose intolerance, renal Fanconi syndrome Treatment: Diet similar to that for diabetes, high fructose intake to maintain normoglycemia, replacement of renally lost [merckmanuals.com]
Differentiating patients with GSD type III from those with GSD type I solely on the basis of physical findings is not easy, but the hepatomegaly, increased liver glycogen content, fasting hypoglycemia, and muscle weakness are consistent with Cori disease [usmle.biochemistryformedics.com]
None of the patients experienced symptomatic fasting hypoglycemia at the time of diagnosis or during the follow-up period. [bmcmedgenet.biomedcentral.com]
As a consequence, patients with GSD type I have fasting hypoglycemia. Despite the metabolic block, the endogenous glucose formation is not fully inhibited. [emedicine.medscape.com]
Interrelationships of metabolic pathway disruption in von Gierke disease : In the absence of glucose-6-phosphatase activity free glucose cannot be release from the liver contibuting to severe fasting hypoglycemia. [themedicalbiochemistrypage.org]
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Triglycerides Elevated
They often show signs of transaminase and triglyceride elevation, but cirrhosis is very rare 4. [path.upmc.edu]
Colonoscopy
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Polyps
Review the latest developments in the field and get up-to-date clinical information on hot topics like polyps, capsule endoscopy, and pancreatic treatments. [books.google.com]
Biopsy
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Liver Biopsy
Diagnostic methods Biochemical diagnosis is made by measuring phosphorylase kinase activity in blood cells or in a liver biopsy. Some patients may have normal activity in red blood cells (XLG2 variant). Serum transaminase levels may be elevated. [orpha.net]
Liver biopsy revealed an increase in the glycogen content (6 percent of wet weight). In which of the following enzymes is a genetic deficiency most likely for this patient? A. Branching enzyme B. Debranching enzyme C. Glucose-6-phosphatase D. [usmle.biochemistryformedics.com]
One patient who was referred from an outside hospital was reported to be PAS in liver biopsy, but limited information was available because the liver biopsy had been performed at the outside hospital. [bmcmedgenet.biomedcentral.com]
Treatment
Management and treatment Most patients require no specific treatment. Hypoglycemia can be controlled by adequate dietary treatment (frequent meals rich in carbohydrates, and supplements of uncooked starch). [orpha.net]
Review the latest developments in the field and get up-to-date clinical information on hot topics like polyps, capsule endoscopy, and pancreatic treatments. [books.google.com]
Prognosis
Prognosis The clinical course is benign with patients reaching their full height and weight during adulthood. Life expectancy is normal. The documents contained in this web site are presented for information purposes only. [orpha.net]
Prognosis (prediction of future health) is generally considered good for the liver forms of the disease; however, prognosis for the muscle forms is still unknown. [agsdus.org]
Prognosis - Glycogen storage disease type 6- due to phosphorylation Not supplied. Treatment - Glycogen storage disease type 6- due to phosphorylation Not supplied. Resources - Glycogen storage disease type 6- due to phosphorylation Not supplied. [checkorphan.org]
Newer treatment possibilities provide hope for an improved outlook (prognosis). Most people with a glycogen storage disorder respond well to treatment. [patient.info]
Etiology
Etiology Phosphorylase kinase (PhK) is an enzyme which plays a key role in the regulation of glycogenolysis as it is required for glycogen phosphorylase activation. [orpha.net]
Localization myopathic GSD cardiac GSD hepatic GSD Etiology GSD MIM. Deficiency Eponym Gene MIM. [humpath.com]
Ongoing controversies regarding etiology, diagnosis, treatment In 2002, guidelines from the European Study on Glycogen Storage Disease Type I (ESGSDI) recommended liver transplantation in patients with type I GSD and unresectable hepatocellular adenomas [clinicaladvisor.com]
Development of guidelines to allow for systematic review and microarray studies are needed to better delineate the etiology of the HCC in patients with GSD-III. There are usually periportal fibrosis, and sometimes progress to micronodular cirrhosis. [wjgnet.com]
Epidemiology
Summary Epidemiology It is the most common presentation of glycogen storage disease due to PhK deficiency (see this term) with an incidence estimated at less than 1/100,000 births. [orpha.net]
Glycogenosis type 9E - Glycogenosis type IXd - Glycogenosis type IXe Classification (Orphanet): - Inborn errors of metabolism - Rare genetic disease - Rare neurologic disease Classification (ICD10): - Endocrine, nutritional and metabolic diseases - Epidemiological [csbg.cnb.csic.es]
Lamp-2 : Xq24 Phosphorylase (McArdle's), severe phenotype: 11q13 Triosephosphate isomerase : 12p13 Acid Maltase Deficiency (Glycogen storage disease 2 (GSD2); Pompe disease) Acid α-1,4-glucosidase (GAA) ; Chromosome 17q25.3; Recessive Nosology: LGMD 2V Epidemiology [neuromuscular.wustl.edu]
Relevant External Links for PHKB Genetic Association Database (GAD) PHKB Human Genome Epidemiology (HuGE) Navigator PHKB Atlas of Genetics and Cytogenetics in Oncology and Haematology: PHKB No data available for Genatlas for PHKB Gene Phosphorylase-kinase-deficient [genecards.org]
Pathophysiology
Pathophysiology Metabolic Pathway Metabolic pathways showing defects in various glycogen storage diseases, (ɔ) Image courtesy of WikiDoc.org, by " Dr. [wikidoc.org]
Prevention
The Lipid Research Clinics Coronary Primary Prevention Trial Results, II: the relationship of reduction in incidence of coronary heart disease to cholesterol lowering. [books.google.es]
Avoiding exercising in extreme heat helps prevent heat cramps. Heat cramps can also be avoided by taking salt tablets and water before prolonged exercise in extreme heat. [the-medical-dictionary.com]
Uncooked (raw) cornstarch (1-1.5 grams per kg) administered at bedtime prevents morning hypoglycemia and ketosis. Daytime hypoglycemia tends to be mild and snacks every 2 to 4 hours prevent hypoglycemia. [clinicaladvisor.com]
For some children, eating several small meals rich in sugars and starches every day helps prevent blood sugar levels from dropping. Cornstarch. [childrenliverindia.org]
Prevention There is no way to prevent GSDs. However, early treatment can help control the disease once a person has it. If you have a GSD or a family history of the disorder, you may want to consult a genetic counselor. [cancercarewny.com]