A rare case of facioscapulohumeral muscular dystrophy and myasthenia gravis
A 70-year-old man presented to our department with complaint of 15-day history of progressive difficulty in chewing and dysartheria. He had a 50-year history of slowly progressive asymmetrical weakness of proximal upper limb muscles.\nExaminations revealed reduction in forces of bilateral orbicularis oculi muscles, weakness and wasting of bilateral triceps muscles especially on right side and bilateral winging of scapula more prominent on right side. The legs and pelvic girdle muscles had normal forces. The reflexes were somewhat depressed throughout. Sensation and coordination were normal. The patient's gait was normal.\nSerum creatine kinase values and other laboratory data were normal. Computerized tomography of the thorax was normal. Nerve conduction studies showed decrement response on repetitive nerve stimulation. Concentric needle electromyography showed myopathic changes especially in proximal limb muscles. Edrophonium test was performed and dysartheria and chewing difficulty showed dramatic improvement but had no effect on limb weakness. Serum anti-acetylcholine receptor (AchR) antibody level was markedly elevated. Muscle biopsy showed myopathic changes with invariability in muscle fiber size, intramuscular infiltration of chronic inflammatory cells, mostly lymphocytes, few hyaline fibers and prominent fat infiltration. Subsequent genetic analysis confirmed the diagnosis of FSHD. Our patient's bulbar symptoms showed dramatic improvement following administration of choline-esterase inhibitor agents.