DMD long case

Question 1

Diagnosis

Answer 1

genetic mutation/how diagnosed

Question 2

specific problems to elicit

Answer 2

1. Functional Abilities (ADL - dressing, writing, toileting)
   T
   H
   E
   F GI problems (constipation, incontinence, GORD, vomiting)
   I) difficulties with micturition/ constipation
   B) scoliosis (progression and any planned surgeries)
   S) joint contractures (AFOs. night splints)

P)
I) Schooling, intellect
B) behavioural/psychological problems (ADHD), OCD, anxiety, depression, aggression
S: Respiratory problems (sx of resp failures at later stage, sleep disordered breathing, non invasive ventilation)
Cardiac sx (arrythmias, sx of cardiac failure)

HEARTS
1. Mobility (long leg braces, wheelchair)
3. Home Mods (ramps, bathroom fittings, specialised beds and mattresses)
4. Transport need (van with hoist)
11. school (access problems, educational problems, help needed, attitudes of teacher)

Question 3

specific questions re: DMD

Answer 3

1. Initial diagnosis (when, where, presenting sx, clumsiness, muscle cramps, learning delay, cognitive impairment, global or gross motor developmental delay)
2. time between sx and diagnosis
3. what invx were undertaken
4. stages of deterioration
5. number of hospitalisations
6. development of complications (scoliosis/cardiac failure)
7. surgical procedures (e.g. release of contractures)
8. commencement of steroids: timing, side effects

Question 4

Social impacts

Answer 4

1. Difficulties at school, poor job prospects, limitations on lifestyle, body image, self esteem, peer reaxtion
2. impact on family (parental coping, difficutlies between mother and father, genetic implications for further children,
3. financial considerations, such as cost of wheelchairs, home mods, transport, hospitalisations, private hwalth
4. physical burden of heping children in and out of wheelchairs
5. benefits recieved
6. social supports (social worker, DMD family support group provided by muscular dystrophy association, visits to school by OT, and community liaison nurse from hospital muscle clinic to meet class and teachers.

Question 5

Examination of DMD

Answer 5

1. describe resting posture; or stnading posture if able.
   interscapular muscle bulk, small proximal upper limb musculature, abnormal anterior axillary fold (atrophic sternal head of pectoralis major), lumbar lordosis, some internal rotation of the femurs 9due to muscle imbalance), small thighs with preservation of the vastus lateralis, but prominent calves (pseudohypertroiphy), and equinus deformity of the feet.
   Respiratory status

Question 6

Management priorities in DMD (general)

Answer 6

Multidisciplinary approach ensuring there is a neurologist, geneticist, respiratory physician, cardiologist, orthopaedic surgeon, physiotherapist, occupational therapist, orthotist, clinical nurse coordinator and social worker

Question 7

My role as paediatrician is to

Answer 7

1) keep full contact with the team regarding changes in medical care, being able to coordinate overall medical care
2) dealing with any problem’s that arise between clinic visits, such as manageing intercurrent infections.
3) The general paediatrician should probably be the principle advisor/counsellor on this case, however this is seldom the case - this might be an issue.

Question 8

Medical management of DMD

Answer 8

glucocorticoids can slow down the decrease in strength and function in DMD. Moderate doses are useful when boys are still walking, to improve motor function.
also delays progression of cardiomyopathy.
Prednisone is immunosuppressive, and also has direct effects on muscle cells. It can modulate proteolysis and calcium handling, increase myogenesis and inhibit apoptosis.

max dose in DMD should be 30-40mg per day for 2 years, and effect can be sustained for 2 years)

Question 9

Steroid side effects?

Answer 9

growth: weight gain and reduced linear growth
2) Hypertension
3) cushingoid appearance
4) immune suppression
5) diabetes (secondary to sustained hyperglycaemia)
6) cataracts
7) osteoporosis + long bone compression fractures
8) mood dysregulation
9 easy bruising

Question 10

how would you manage side effects in DMD, when this is the only medication that works?

Answer 10

dose reductions (down to 0.3mg/kg)
alternative dosing regimens or nighttime dosing may overcome these problems.

Question 11

are there any alternatives to prednisolone ?

Answer 11

Deflazacort (a derivative of prednisolone); which enhances cardiac function and attenuates the development of scoliosis, including when ambulation is lost.)

Question 12

what do I monitor when a child is on steroid therapy?

Answer 12

1. assessing benefits (timed muscle function tests, PFTs; noting the age when independent walking is lost)
2. Assessing risks: monitoring for SEs.
   steroid should not be given up until other rergimens have been explores.
   Ensuring patients have a medicalert bracelet -

Question 13

Rehabilitation management goals and strategies?

Answer 13

the maintanance of muscle extensibility, and the avoidance of joint contractures, are achieved by stretching, guided by physiotherapist and occupational therapists.

Night splinting, using custom made Ankle Foot Orthoses, can assist control of contractures of the ankle.

powers wheelchairs with or without standing function are used once ambulation becomes untenable. resting hand splints may be needed for tight long flexors of the fingers.

Question 14

what role does physio play in DMD

Answer 14

1. encourage walking and avoid joint deformity
2. stretches for contractures
3. exercises for strength while muscles still strong enough
4. chest physiotherapy for respiratory problems
   - motivational breathing exercises
   - negative pressure insufflation (cough assist)

Question 15

What roles does OT play in DMD

Answer 15

1. prescribing specifications for wheelchairs and equipment
2. home visits and visits to school, for Q&A with teachers
3. Advice re: aids to ADLS
4. Aiding posture: avoidance of certain positions
5. Ax and advice on installation of ramps for adequate mobility at home. Ax need for lifting machines (dependent on strength of caregiver at home), bathroom access

Question 16

Equipment required in DMD

Answer 16

1. wheelchairs: manual type fr around 9 years; powered from 11 years
2. inclined standing board, to stretch tendo achilles
3. prone board
4. standing desks, or lying on prone board
5. swivel feeders
6. Hoists, mobile and fitted to car.

Question 17

what role does orthopaedic surgery play?

Answer 17

1. management of long bone # with internal fixation.
2. elongation of tendo achilles if still walking
3. tendo achilles tenotomiies, tibialis posterior transfer.

Question 18

Scoliosis management

Answer 18

without corticosteroids there is a 90% chance fo developing scoliosis.
xrays should be done 12 monthly if cobb angle is less than 15 degres and 6 monthly if over 15 degrees. A proper seating system in the wheelchair is very important, avoiding asymmetrical contractures when still ambulatory.

Question 19

risks of scoliosis?

Answer 19

1. respiratory function (restrictive lung disease)
2. feeding and GORD
3. comfort and pain
4. appearance, body image and posture

Question 20

criteria for spinal fusion

Answer 20

1.
Before the primary curve becomes greater than 20–25% if not receiving steroids, or greater than 40% if receiving steroids.

2.
Progressive curve.

3.
Substantial growth capacity remaining.

4.
Patient physically, and emotionally, fit for surgery.

5.
Vital capacity has not gone below 50% predicted for height, although some units use the value 30%, but the risks are greater; surgery should occur in a tertiary centre.

6.
Cardiac function, as demonstrated on echocardiography, must be satisfactory.

Question 21

why is bone health a concern in DMD?

Answer 21

1. decreased mobility
2. weakness
3. steroids

Question 22

annual screening recommendations for bone health (annually)

Answer 22

1. CMP
2. Alk Phos
3. 25-hydroxyvitamin
4. PTH
5. urine calcium
6. spine xray, bone age and dual energy xray scanning for bone mineral density
   7.

Question 23

assessment for pubertal delay secondary to long term steroid use?

Answer 23

hormonal status (FSH, LH and sex steroids)
consultation with an endocrinologuist

Question 24

how to manage lung disease in DMD

Answer 24

• secondary to weakness of the diaphragm, chest wall and abdominal musculature. worsening respiratory resever and sleep hypoventilation, OSA.
  1. treat recurrent LRTI aggressively, as they can tip over into overt resp failure; inhaled bronchodilators, mucolytics, or antibiotics. must not be exposed to tobacco smoke, should be fully immunised inc. yearly influenza vaccine.
  2. They may develop cor pulmonale secondary to hypoxia, due to ventilatory difficulties and ventilation–perfusion inequalities associated with scoliosis.
  3. hypoventilation and hypercapnia can respond well to BiPAP

Question 25

What monitoring should be done for lung health?

Answer 25

1. Monitor with regular (6-monthly) pulmonary function tests (PFTs),
   a) forced vital capacity (FVC) and maximal inspiratory and expiratory pressure, the former reflecting diaphragmatic strength
   b) the latter reflecting the strength of the chest wall and abdominal muscles, correlating with the ability to cough and clear secretions.
   c) FVC predicts the development of hypercapnia and survival. When the FVC falls below 50%, this is the time to consider non-invasive ventilation.
   Peak cough flow, maximum expiratory mouth pressure.

Question 26

when nocturnal BIpap is not sufficient?

Answer 26

discussions about whether to go into long term 24 hour ventilation have to be made in consultation with the respiratory physician. risks of significant deterioration increase when not on daytime NIV as well.

Question 27

when would volume ventilators be used?

Answer 27

When vital capacity is below 40%
The next step is a tracheostomy.

Question 28

cause of death?

Answer 28

The usual cause of death in most texts and journals has usually been given as RLD, but in patients who are already receiving non-invasive ventilation, the main determinant of survival is cardiac status. Of patients receiving NIV who died under the age of 30, over half died of cardiomyopathy.

Question 29

cardiac management?

Answer 29

Ventricular remodelling can occur in patients with DMD (or BMD) if treated early enough with an ACE inhibitor such as lisinopril or perindopril (or angiotensin II receptor blockers [ARBs] such as losartan, if intolerant of ACE inhibitor) and/or a beta blocker, such as metoprolol or carvedilol. If there is overt heart failure, digoxin and diuretics may be needed. This treatment can lead to normalisation of left ventricular size and systolic function. Arrhythmias occurring may warrant periodic Holter monitoring.

Question 30

when to start cardiac treatment?

Answer 30

Treatment with ACE inhibitors or beta blockers typically is commenced when cardiac imaging shows ventricular dysfunction, the left ventricular ejection fraction (LVEF) is below 55% and fractional shortening (FS) is under 28%, or there is dilatation of the left ventricle.

Question 31

anesthetic risks?

Answer 31

Malignant hyperthermia-like reactions can occur (which can lead to hyperkalaemia, rhabdomyolysis and cardiac arrest), as can anaesthesia-induced rhabdomyolysis (AIR) (elevated K+ or creatine kinase [CK] without hyperthermia). Depolarising muscle relaxants (suxamethonium chloride; also called succinylcholine) and inhalational agents (halothane, isoflurane, sevoflurane) should be avoided

Question 32

psychosocial management?

Answer 32

1. Education of parents, patient and school. Clarification of misinformation from other sources requires multiple informative sessions with the various disciplines involved in the comprehensive management of these patients. The school must be informed about DMD.
2. as with many chronic diseases, the incidence of depression and affective disorders is higher in children and adolescents with DMD and needs to be screened for.