• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
GLYCOGEN STORAGE DISORDERS
 

GLYCOGEN STORAGE DISORDERS

on

  • 288 views

 

Statistics

Views

Total Views
288
Views on SlideShare
288
Embed Views
0

Actions

Likes
0
Downloads
3
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    GLYCOGEN STORAGE DISORDERS GLYCOGEN STORAGE DISORDERS Presentation Transcript

    • GLYCOGEN STORAGE DISORDERS These are a group of inherited disorders associated with glycogen metabolism, familial in incidence and characterized by deposition of normal or abnormal type and quantity of glycogen in the tissues
    • There are 6 classical types of glycogen storage diseases  Type1)Von gierke’s disease Type2)Pompe’s disease Type3)Limit dextrinosis(Forbe’s disease) Type4)Amylopectinosis(anderson’s disease) Type5)McArdle’s disease Type6)Her’s disease
    • TYPE 1:Von gierke’s disease  ENZYME DEFICIENCY :glucose-6phosphatase  INHERITANCE : Autosomal recessive  Liver cells and intestinal mucosal cells are fully loaded with glycogen and metabolically unavailable
    • CLINICAL AND BIOCHEMICAL FEATURES OF VON GIERKE’S DISEASE  Only little amount of glucose is available is derived from liver  So the children with this disease may tend to develop hypogycemia  Fat is used as a energy source so it may lead to LIPAEMIA,ACEDEMIA and KETOSIS  Excess of Acetyl coA is diverted for chosterol synthesis this may lead to elevated level of cholestrol and results in XANTHOMAS
    • Cont….  Increased fatty acid synthesis can produce fatty infiltration of liver  PERSISTENT HYPOGLYCAEMIA has 2 effects Hypoglycemia inhibits insulin which in turn inhibits protein synthesis which results in DWARFISM Hypoglycemia stimulates the secretion of CATECHOLAMINES which cause muscle glycogen to break down producing lactic acid and LACTIC ACIDOSIS  Increased blood lactic acid competes with urate excretion by kidneys leading to increased blood uric acid levels  Children with increased uric acid synthesis may develop the symptoms of GOUT
    • PROGNOSIS Children with this disease may die young and some of them survive till adolescence
    • TYPE 2: POMPE’S DISEASE  ENZYME DEFICIENCY : ACID MALTASE enzyme which is present in lysosome and catalyses the breakdown of oligosaccharides  INHERITANCE : AUTOSOMAL RECESSIVE  Here the glycogen structure is normal and the organs which are involved is HEART,LIVER,SMOOTH MUSCLE,AND STRAITED MUSCLE  All the tissue contain excess of glycogen
    • CLINICAL FEATURES  Enlargement of heart (cardiomegaly)  Muscle weakness
    • PROGNOSIS  Infants usually die due to cardiac failure and broncho pnuemonia  Death usually occurs before 9 months
    • TYPE 3 : LIMIT DEXTRINOSIS(FORBE’S DISEASE)  ENZYME DEFICIENCY : DEBRANCHING ENZYME  INHERITANCE : AUTOSOMAL RECESSIVE  GLYCOGEN STRUCTURE : LIMIT DEXTRIN TYPE  Organs involved are heart liver and muscle
    • CLINICAL AND BIOCHEMICAL FEATURES • • • • • HEPATOMEGALY MODERATE HYPOGLYCEMIA ACIDOSIS PROGRESSIVE MYOPATHY Enzyme deficiency can be demonstrated in leucocytes
    • PROGNOSIS  Survives well to adultlife
    • TYPE 4 : AMYLOPECTINOSIS(ANDERSON’S DISEASE)  ENZYME DEFICIENCY : BRANCHING ENZYME  INHERITANCE : NOT DEFINETELY KNOWN  Glycogen deposited is abnormal type, few branch points and very long inner and outer unbranched chains  LIVER is the mainly affected organ and other organs are HEART, KIDNEY, and MUSCLES  Deposition is seen in RE SYSTEM
    • CLINICAL AND BIOCHEMICAL FEATURES  HEPATOMEGALY  SPLENOMEGALY  MODERATE HYPOGLYCEMIA  NODULAR CIRRHOSIS OF LIVER  HEPATIC FAILURE  Enzyme deficiency can be demonsrated in leucocytes and liver
    • PROGNOSIS  Usually fatal  Longest survival is reported as 4 years
    • TYPE 5 : McArdle’s disease  ENZYME DEFICIENCY : MUSCLE PHOSPHORYLASE  INHERITANCE : AUTOSOMAL RECESSIVE  Glycogen deposited in normalstructure and the organs involved are skeletal muscles
    • CLINICAL FEATURES Muscle cramps on exercise Pain Stiffness and weakness of muscles
    • EPINEPHRINE TEST  After administration of epinephrine rise in blood glucose occurs which shows that hepatic phosphorylase activity is normal
    • TYPE 6 : Her’s disease ENZYME DEFICIENCY : LIVER PHOSPHORYLASE Glycogen deposited is normal in structure Organs affected are mainly LIVER and LEUCOCYTES
    • CLINICAL AND BIOCHEMICAL FEATURES  HEPATOMEGALY  MODERATE HYPOGLYCEMIA  MILD ACIDOSIS