Neuromuscular disorders Flashcards
Most common form of motor neuron disease in adults
Amyotrophic lateral sclerosis
More common with increasing age
Most common presenting symptom of ALS
Weakness in a focal area, gradually spreading to contiguous muscles. Another important sx is profuse and continuous fasciculations
Exam signs of ALS
Mix of UMN and LMN signs
Other (non-motor) features of ALS
Cognitive impairment, emotional incontinence,
MC causes of death in ALS
Respiratory failure and pneumonia
Symptomatic management of ALS (no cure)
BiPAP can prolong survival and improve QOL
PEG tubes for severe dysphagia
Treat cramps, spasticity, aspiration, reduced mobility
Common causes of plexopathies
Cancer Radiation therapy Metabolic disorders (DM) Trauma Idiopathic/autoimmune
When to suspect plexopathies
When patient has symptoms that would seem to be due to a radiculopathy, but the symptoms do not conform to a certain dermatome
Mnemonic for causes of polyneuropathy
Diabetes
Alcohol (probably actually 2/2 malnutrition)
Nutritional (B12, B1, B6, E deficiencies)
Guillain-Barre (AIDP)
Toxic (lead, arsenic, excess B6, meds)
HEreditary
Recurrent (CIPD)
Amyloid
Porphyria
Infectious (leprosy, HIV, Lyme, diphtheria, mono)
Systemic (uremia, hypothyroid, lupus, Sjogrens, Wegener’s)
Tumors (paraneoplastic, multiple myeloma can cause CIPD)
Presentation of myophosphorylase deficiency (McArdle’s disease)
Asymptomatic at rest, then pain, cramping, and fatigue within minutes of forceful exertion
Sometimes, second wind after initiation of fatty acid oxidation
Presentation of carnitine palmitoyltransferase (CPT) deficiency
Pain, cramps, and weakness after prolonged exercise
No “second wind” phenomenon
Patients admitted with neuromuscular disease should have daily respiratory monitoring for what metrics?
FVC and negative inspiratory force
FVC below 10-12ml/kg –> require elective intubation
(intubate sooner (<15) if rapidly deteriorating)
