DMD Flashcards
DMD primarily affects which muscles?
quadracepts and gluteal
Which type of myofibers are affected?
Fast twich Tyoe 2B
Characteristics of DMD
muscle wasting
weakness
myofiber size variation with muscle necrosis
fat accumulation
paradoxical hypertrophy of calf muscles
DMD is a gene mutation on?
Xp21
What protein is dysrupted?
Dystrophin which is primarily located in skeletal muscle
loss of ambulation and caridiopulmonary compromise occurs by age
20
function of dystrophin
stabilize plasma membrane maintain stregnth of muscle fibers
Considered a ___ mypoathy
proximal
Genetic RF
X linked,
Males > females
women must have a defective gene on both X alleles to have a severe presentation
Chance in future pregnancies
50%
Average life expectancy
mid 30’s
Ultimate cause of death
progressive to cardiomyopathy and pulmonary failure
average age at loss of ambulation
9-10 years old
steriods prolong this by 2-3 years
Endocrine
Delayed puberty
alterations in growth
diabetes, adrenal insufficiency
educate parents on adrenal crisis
obesity
disposed to OSA
vision problems
steroids can cause cataracts
dental problems
due to bone density
orthopedic concerns
osteoporosis
scoliosis
fractures
decreased ROM, contractures and pain
GI disturbances
dysphagia, constipation, GERD, FTT, gastroporesis, vitamin deficiencies
Cardiovascular
progressive cardiomyopathies-> HF
hypercholesterolemia & hypertension
Respiratory
recurrent pneumonias
progressive -> respiratory failure
psychosocial concerns/co-conditions
ADHD
learning disabilities
language disorders
autism
history clues (3)
Family member with DMD
incidental lab findings
complications with anesthesia
abnormal labs
elevated CK, transaminases or myoglobinuria
Common anesthesia complications
rhabdomyolysis
malignant hyperthermia
Common presenting s/s (8)
tow walking
gowers sign
muscle atrophy
fatigue
difficulty climbing stairs
global developmental delay
speech delay
FTT
Global developmental delay
may be the primary presentation
Red flags (3)
delayed motor development-
(esp age of ambulation or gait abnormalities)
FTT
Not walking by 18 months
Average age at presentation
2-3 years
Average age at diagnosis
3-5 years
When do we test for DMD?
elevated CK, fam hx along with any suspicion of muscle abnormailty, not walking by 18m, persistant toe walking, presence of gowers sign
Gold standard for diagnosis
serum CK based on H&P suspicions
If CK is elevated then..
genetic testing for gene mutation is recommended
If genetic testing is inconclusive then…
muscle boipsy is warranted
What is confirmatory for DMD after muscle biopsy?
absence of dystrophin in muscle biopsy
Treatment
Prednisode dose
0.75mg/kg/day
Treatment
Deflazacort
0.9mg/kg/day
When should steriod treatment begin?
early ambularoty phase before major physical decline begins
When is follow up after starting steriods?
At one month
then Q 2-3 months until on stabilized dose with minimal side effects
Dose is titrated down to decrease s/e
Steriods should never be
stopped abruptly
educate parents
Patient should carry
card provided by neuromuscular specialist
Initiation of ARB or ACE inhibitor by age
10 t preserve cardiac function
female carriers
refer to cardio at diagnosis, can be asymptomatic and have silent cardiomyopathies
FVC testing from pulm at what age?
5-6 years old
when is weight gain most common?
initiation or steriods
loss of ambulation
weight loss can occur from
progressive dysphagia
diet
rich in nutrients, low calories/cholesterol
adequate vitamin D and calcium
Immunizations recommended
All plus flu, prevnar 13 and pneumovax 23
what is considered immunocompromised for vaccination purposes?
taking >2mg/kg/day
should not recieve live vaccines
give them prior to starting steriods
2 doses of MMR can be given 4 weeks apart
Dental risk
at increased risk for osteoporotic fractures and necrosis of the jaw
consider flouride supplementation if not city water
nonpharmacologic management
weight bearing exercise, diet, massage therapy
menatl heath screening tool for children
stregnths and difficulties questioner for children
Mental health screening tool for parents
parents of 5-17 year olds
personal adjustment and role skill scale evaluates coping mechanisms
How frequent are well visits?
Every 6 months
when should transitioning to an adult provider begin?
12 years old
resources for families
MDA
CDC guide for families
