| Phosphorylase Deficiency (MPD or PYGM) (Also known
as McArdle's Disease) |
| Onset: |
Childhood to adolescence. |
| Symptoms: |
Muscle cramps usually occurring after exercise. Intense exercise can cause
muscle destruction and possible kidney damage. |
| Progression: |
Variable severity and progression. |
| Inheritance: |
Autosomal recessive. |
| Acid Maltase Deficiency (AMD) (Also known
as Pompe's Disease) |
| Onset: |
Infancy to adulthood. |
| Symptoms: |
In infant form, disease is generalized and severe, with heart, liver and
tongue enlargement common. Adult form involves weakness of upper arms and
legs, trunk and respiratory muscles. |
| Progression: |
Progression varies. |
| Inheritance: |
Autosomal recessive. |
| Phosphofructokinase Deficiency (PFKM) (Also known
as Tarui's Disease) |
| Onset: |
Childhood. |
| Symptoms: |
Muscle fatigue that, upon exercise, can lead to severe cramps, nausea,
vomiting, muscle damage and discoloration of urine. |
| Progression: |
Progression varies widely. |
| Inheritance: |
Autosomal recessive. |
| Debrancher Enzyme Deficiency (DBD) (Also known as
Cori's or Forbes' Disease) |
| Onset: |
Early childhood in first year. |
| Symptoms: |
Generalized weakness and muscle wasting. Enlarged liver in infancy. Episodes
of low blood sugar. |
| Progression: |
Slow to variable progression. Muscular symptoms may be delayed until early
teens and adulthood. |
| Inheritance: |
Autosomal recessive. |
Mitochondrial Myopathy
(MITO) |
| Onset: |
Early infancy to adulthood. |
| Symptoms: |
Generalized muscle weakness, flaccid neck muscles and inability to walk.
Brain is often involved, with seizures, deafness, loss of balance and vision,
and retardation common. |
| Progression: |
Wide variety of progression and severity. |
| Inheritance: |
Maternal mitochondrial gene (mtDNA). |
| Carnitine Deficiency (CD) |
| Onset: |
Early childhood. |
| Symptoms: |
Varied weakness of shoulders, hips, face and neck muscles. |
| Progression: |
Progression varies and carnitine supplementation is often effective. |
| Inheritance: |
Autosomal recessive. |
| Carnitine Palmityl Transferase Deficiency
(CPT) |
| Onset: |
Young adulthood. |
| Symptoms: |
Inability to sustain moderate prolonged exercise. Prolonged exercise and/or
fasting can cause severe muscle destruction with urine discoloration and
kidney damage. |
| Progression: |
Severity varies. |
| Inheritance: |
Autosomal recessive. |
| Phosphoglycerate Kinase Deficiency
(PGK) |
| Onset: |
Childhood to adolescence. |
| Symptoms: |
Muscle pain and weakness, with muscle damage and urine discoloration possible
after vigorous exercise. |
| Progression: |
Severity varies. Avoid intense exercise. |
| Inheritance: |
X-linked recessive, autosomal recessive. |
| Phosphoglycerate Mutase Deficiency
(PGAM or PGAMM) |
| Onset: |
Childhood to adulthood. |
| Symptoms: |
Muscle pain, cramps, muscle damage and urine discoloration possible during
intense exercise of brief duration. |
| Progression: |
Severity varies. Avoid intense exercise. |
| Inheritance: |
Autosomal recessive. |
| Lactate Dehydrogenase Deficiency
(LDHA) |
| Onset: |
Childhood to adolescence. |
| Symptoms: |
Exercise intolerance with muscle damage and urine discoloration possible
following strenuous physical activity. |
| Progression: |
Severity varies. Avoid intense exercise. |
| Inheritance: |
Autosomal recessive. |
| Myoadenylate Deaminase Deficiency
(MAD) |
| Onset: |
Early adulthood to middle age. |
| Symptoms: |
Muscle fatigue and weakness during and after exertion, with muscle soreness
or cramping. May not attain prior performance levels.. |
| Progression: |
Severity varies. Usually nonprogressive and non-debilitating. |
| Inheritance: |
Autosomal recessive. |
