- © 2016 Marshfield Clinic
Immune Mediated Necrotizing Myopathy: a Cause of Isolated Myopathy of Neck Extensor Muscle
- Rahul Sehgal, MD*⇑,
- Rafael Medina-Flores, MD†,
- Ralph Yachoui, MD* and
- Charles V Kenney, MD‡
- *Department of Rheumatology, Marshfield Clinic, Marshfield, Wisconsin, USA
- †Department of Lab/Pathology, Marshfield Clinic, Marshfield, Wisconsin, USA
- ‡Department of Radiology, Marshfield Clinic, Marshfield, Wisconsin, USA
- Corresponding Author
: Rahul Sehgal, MD, Department of Rheumatology, Marshfield Clinic, 1000 North Oak Avenue, Marshfield, WI 54449 USA, Tel: (715) 389-3366, Email: sehgal.rahul{at}marshfieldclinic.org
Abstract
Immune mediated necrotizing myopathy (IMNM) is a unique form of myositis that is characterized by distinct muscle biopsy features including abundant myofiber necrosis, degeneration, and regeneration with only minimal, if any, inflammation on muscle biopsy. IMNM is clinically similar to idiopathic inflammatory myopathy (IIM); hence, muscle biopsy is essential to diagnose IMNM. Herein we describe a case of neck extensor weakness due to necrotizing myopathy. Isolated weakness of the neck extensor muscles is uncommon in IIM and IMNM. This case describes the diagnostic work-up, treatments utilized, and 2 year follow-up course without involvement of other muscle groups and without progression of neck extensor muscle weakness. Advanced imaging using magnetic resonance imaging (MRI) facilitated the diagnosis by identifying the affected muscles and site for muscle biopsy.
