Case Presentation: Misdiagnosis of a Patient With ALS

Henry P, a 78-year-old white man, presents for evaluation because he recently fell while crossing the street. He states that he lost his balance on a windy day but is not sure what caused him to fall. Mr P states he has been having difficulty lifting his grapefruit spoon with his left hand in the morning. He also complains that he has noticed his signature has gotten smaller over the last year and that he struggles to button and unbutton his dress shirt.

Mr P’s vital signs are as follows: temperature, 97.8°F; heart rate, 65 beats/min; respiratory rate, 14 beats/min; and blood pressure, 115/80 mm Hg. Mr P’s physical examination is unremarkable except for minor fasciculations in his upper extremities and positive Babinski sign during the musculoskeletal examination. Mr P does not have a significant medical or family history, and he has not traveled recently. He denies smoking and recreational drug use, and he states that he exercises regularly and eats a clean diet.

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Mr P is diagnosed with Parkinson-plus syndrome and corticobasal ganglionic degeneration based on the results of electromyography (EMG), which does not show denervation.

Three Years Later

At the time of his initial presentation, Mr P was experiencing balance issues, asymmetric upper extremity weakness, difficulty with fine motor movements, fasciculations, and hyperactive superficial reflexes. Even though these symptoms may be indistinct separately, together they suggest the onset of ALS and should have been further investigated by his primary care provider.

Falling on a windy day and a positive Babinski sign suggest balance deficiencies and lack of coordination, while difficulty buttoning his shirt and smaller handwriting demonstrate stiffness with fine motor movements of the upper extremities; all of these findings are suggestive of an upper motor neuron lesion.  Fasciculations in the upper extremities and Mr P’s complaint of difficulty lifting a grapefruit spoon with one hand — indicative of asymmetric upper extremity weakness — suggest a lower motor neuron lesion. Therefore, signs of both upper and lower motor neuron lesions were present at Mr P’s initial appointment. Although these symptoms could be reflective of the patient’s advanced age, Mr P should have been evaluated for progression of these symptoms with periodical physical examinations, EMGs, and nerve conduction studies to either rule out or confirm a diagnosis of ALS.

By the time Mr P was diagnosed with ALS, which was 3 years after his initial presentation, he had lost his ability to speak or move his left arm, and swallowing had become more difficult. Because of his delayed diagnosis, Mr P received limited benefit from appropriate pharmacologic and therapeutic interventions, including the ALS clinic.

At the end stages of his disease, Mr P decided to halt nutrition intake and only continue comfort measures for treatment. He died 10 months after being diagnosed with ALS and 4 years after receiving the initial neurodegenerative diagnosis of corticobasal ganglionic degeneration.

Katherine Salter Huff, MPAS, PA-C,  is a physician assistant at Blue Ridge Orthopedics in Anderson, South Carolina, and Alicia Elam, PharmD, is associate professor in the Physician Assistant Department at Augusta University in Augusta, Georgia.


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