1.
Myasthenia triggered by immune checkpoint inhibitors: New case and literature review.
Gonzalez, NL, Puwanant, A, Lu, A, Marks, SM, Živković, SA
Neuromuscular disorders : NMD. 2017;(3):266-268
Abstract
Immune checkpoint molecules are potent regulators of immunologic homeostasis that prevent the development of autoimmunity while maintaining self-tolerance. Inhibitors of immune checkpoint molecules are used as immunotherapy in the treatment of melanoma and different types of refractory cancer, and can trigger various autoimmune complications including myositis and myasthenia gravis. We describe a case of generalized myasthenia gravis induced by pembrolizumab and review 11 other cases. Five patients also had elevated serum CK levels ranging from 1200 to 8729 IU/L, and biopsy showed myositis in one. Severity was highly variable as symptoms normalized spontaneously in one patient, but three others developed myasthenic crisis (including two with fatal outcomes). Steroids have been recommended as a preferred treatment of autoimmune complications of immune-checkpoint inhibitors. Myasthenia gravis should be considered when weakness, diplopia or bulbar symptoms are seen after treatment with immune checkpoint inhibitors, and additional studies are needed to characterize association with hyperCKemia.
2.
[Macroenzymes: macro-ASAT and macro-CPK. Two cases and literature review].
Etienne, E, Hanser, AM, Woehl-Kremer, B, Mohseni-Zadeh, M, Blaison, G, Martinot, M
La Revue de medecine interne. 2009;(11):963-9
Abstract
INTRODUCTION Macroenzymes are high molecular weight complex formed by the binding of one enzyme and a serum macromolecule, responsible for an increase in the activity of the corresponding enzyme in blood assay. CASE REPORTS We report two cases: firstly, a macro-aspartate aminotransferase (macro-ASAT) discovered in an 82-year-old woman who presented with an isolated and persistent elevation of the ASAT activity that was discovered after sepsis, secondly, a macro-creatine-kinase (macro-CPK) diagnosed in a 62-year-old man after several years of investigations for a persistent CPK elevation. These two case reports allowed us to discuss the mechanism leading to the formation of macroenzymes and the usefulness of their determination. Although macroenzymes are generally non pathologic, they may be associated with auto-immune, neoplastic or infectious diseases. CONCLUSION The possibility of a macroenzyme should be entertained in the presence of an unexplained and isolated increased enzyme activity. It prevents costly and unnecessary investigations.