The Terrible Triad of Checkpoint Inhibition: A Case Report of Myasthenia Gravis, Myocarditis, and Myositis Induced by Cemiplimab in a Patient with Metastatic Cutaneous Squamous Cell Carcinoma

Table 1

Notable abnormal labs on admission and results of autoimmune testing.

Labs on admission	Recorded values	Normal values
Creatine kinase (CK)	6,407 IU/L	22–198 IU/L
High-sensitivity troponin-T	1,557 ng/L	< ng/L
Potassium	5.8 mEq/L	3.5–5.0 mEq/L
Aspartate aminotransferase	532 IU/L	<40 IU/L
Alanine aminotransferase	214 IU/L	<40 IU/L
Urine myoglobin	20 ng/mL	<5 ng/mL
Creatinine	2.14 mg/dL	1.5 mg/dL (for this patient)
Autoimmune antibody testing
Anti-striated muscle antibody titers	1:15,360	<1:120
Acetylcholine receptor antibody levels	9.34 nmol/L	<0.02 nmol/L
Anti-Ro antibody levels	51 U/mL	<20 U/mL