Abstract
A 73-year-old man with a history of hypertension was referred to our department because of progressive frailty while being treated for acute heart failure. Physical examination revealed loss of tendon reflexes in the lower extremities and muscle weakness in all extremities. After close examination, he was diagnosed with Guillain-Barre syndrome (GBS), which was preceded by a Mycoplasma pneumoniae infection. He was given high-dose intravenous immunoglobulin (IVIg) therapy, and his muscle weakness improved. This case suggests that symptoms of neurological disorders in the elderly may be viewed as frailty. Being elderly is a poor prognostic factor for GBS; therefore, early diagnosis and consultation with a neurologist are necessary. Physical examination is essential to differentiate frailty from neurological disorders, and deep tendon reflexes are instrumental in making a diagnosis of GBS.