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Treatment
Table 7. Nervous System Toxicities
7.1 Myasthenia Gravis
Workup/Evaluation:
• Acetylcholine receptor (AChR) and anti-striated muscle antibodies in blood.
If AChR antibodies are negative, consider muscle specific kinase (MuSK) and
lipoprotein related 4 (LPR4) antibodies in blood—while presence of antibodies is
confirmatory, the absence of antibodies does not rule out the syndrome.
• Pulmonary function assessment with negative inspiratory force (NIF) and vital
capacity (VC).
• Creatine phosphokinase (CPK), aldolase, ESR, CRP for possible concurrent myositis
• Consider MRI brain and/or spine depending on symptoms to rule out CNS
involvement by disease or alternate diagnosis.
• Troponin, EKG, and consider transthoracic echocardiogram and/or cardiac MRI to
evaluate concomitant myocarditis (see CV section for further details)
• Electrodiagnostic studies, under neurologic consultation, including neuromuscular
junction testing with repetitive stimulation and/or jitter studies, nerve conduction
study (NCS) to exclude neuropathy, and needle EMG to evaluate for concomitant
myositis
• Inflammatory markers (ESR and CPR).
• Consider paraneoplastic workup.
• Review and stop medications with known risk of worsening myasthenia: beta-
blockers, IV magnesium, fluoroquinolones, aminoglycosides, and macrolide
antibiotics.
Grading Management
All Grades • All grades warrant workup and intervention
given potential for progressive MG to lead to
respiratory compromise. Inpatient admission
may be appropriate at all grades.
No G1 N/A
