Pediatric Myopathies Flashcards
Four general domains of pediatric development.
- Gross Motor
- Fine Motor
- Language
- Cognitive/Social - Emotional and Behavioral
DMD:
- clinical presentation
- **inheritance, pattern
- genetic abnormality
Cannot move against gravity.
- X-linked recessive, frameshift mutation
- absence of dystrophin
What do you do if a child fails a developmental screen?
refer more more testing
BMD:
- clinical presentation
- inheritance, pattern
- genetic abnormality
Can initially move against gravity, but progress to not being able to. ambulatory for another 4 years
- X-linked recessive, frameshift mutation
- dysfunctional amount of dystrophin
Gowers sign
To stand from lying position: A child “walks” their hand up their legs to knees and pushes off to toes to get to a standing position.
seen in DMD and DMD
Presentation of congenital muscular dystrophies
- Present at birth or early infancy - Hypotonia. Severe muscle weakness (proximal>distal), JOINT CONTRACTURES
- May present with: Malformations of the eyes. Malformations of the brain. Cardiomyopathy. Rigid spine
How does GGTP help differentiate between muscle disease and liver disease?
If liver enzymes are elevated (ALT, AST, Aldolase, lactate dehydrogenase) GGTP level can help determine if the liver is involved.
If GGTP is low, then it’s muscle related.
Does congenital myasthenia syndrome involve antibodies?
There are NO ANTIBODIES to acetylcholine receptor and anti‐muscle specific kinase as seen in myasthenia gravis
Spinal Muscular Atrophy clinical picture
AR
• Progressive muscle weakness - Proximal weaker than distal. Absence of deep tendon reflexes. Due to degenerations of:
• Anterior motor neurons
• Brain stem nuclei
Describe statin induced myopathy
Statins can cause: Necrotizing and inflammatory myopathy
• Muscle weakness
• Pain
• Tenderness
CK increases!
What is the importance of serum CK measurement in genetic or acquired muscle diseases.
• Elevation of CK to more than 10 times normal in Statin Induced Myopathy
Mitochondrial myopathies:
- course
- prognosis, when does it present?
- Genetics
• Organs dependent on aerobic metabolism are most affected: Heart, Skeletal muscles, Brain
-Genetics - maternal inheritance if mitochondrial DNA, nuclear gene mutaitons=AD or AR
can present at ANY age - supportive care only
What is M‐CHAT‐R
Modified Checklist for Autism in Toddlers‐Revised
(administer at 18 mos and 24mos)
specifically looks at social interaction and language skills
What development age will:
• Babbles (consonants)
• Sits momentarily
6 months
What development age will: • Momma/dadda (nonspecific) • Pulls up • Cruises • Sits well without support
9months
What development age will:
• Separation anxiety
• Momma/dadda (specific)
• Stacks 3 cubes
1 year
What development age will: • 2 words together • 2/4 of language understood by people who don’t live in the home • Starting interest in potty training • 6 blocks • Copy a line
2 years
What development age will: • Tricycle • 3 numbers, 3 colors, 3 words together • Playing in groups (3 is a group) • 9 blocks • ¾ of speech understood by strangers
3 years
What development age will:
• 4 body parts
• 4/4 (100%) of speech understandable by strangers
• Past tense (b4)
• Copies a cross (1 line at 2 yrs, 2 lines at 4 yrs)
4 years
What development age will:
• Ties shoes
• Skips
• Draws a person with 6 parts
6 years
Males on mom’s side have something - means what inheritance
X-linked recessive
50%
- Rarely have anti ‐gravity neck flexor strength
- Delayed walking, difficulty running
- Broad‐based, waddling, lordotic gait.
- Gowers sign (due to proximal muscle weakness)
DMD
- Ambulation in DMD no longer possible after __ to __ years
- compromised respiratory status by __ or __ decades
- Cardiomyopathy develops in DMD around __ years
12-13
2nd-3rd decade
15 years
- Proximal muscle weakness after 5 years of age
- Maintenance of independent walking until after age 16 years
- Preserve anti‐gravity strength of *neck flexor muscles
- Age of death varies between fourth and sixth decades of life
BMD
live 30-50 years old
Genetics of congenital muscular dystrophies.
AR, mutations in multiple genes
What is this and what is the tx? AR, alpha-glucosidase gene mutation. • Usually presents in early infancy • Generalized weakness and hypotonia • ***Hypertrophic cardiomayopathy*** • Respiratory failure • Feeding difficulty • Hearing loss
Glycogen Storage Disorder type 2 (pompe disease)
• Enzymatic treatments are available (Myozyme) that may help reduce cardiac mass and improve ejection fraction.
What is this: • Muscle stiffness due to myotonia • Relieved by brief exercise • Muscles are generally hypertrophic • Proximal and distal muscle weakness are possible
Myotonia Congenita (Mutation in Cl cnahhel - CLCN 1 geme mutation)
two types of Periodic Paralysis. when do they occur?
(Periodic Paralysis: Repeated episodes of flaccid paralysis of the
4 extremities)
- Hypocalcemic - occurs after exercise and carbohydrate‐rich foods
- Hyperkalemic - occurs while eating potassium‐rich food or during rest after exercise
Labs in muscle disease
- serum CK
- myoglobin (shows up with blood in urine - but no blood in microscopic)
- AST/ALT elevation
what four liver enzymes are also in muscle, so can be elevated?
AST, ALT, aldolase, lactate dehydrogenase
