Disclosures: Ryan McCarter, MD: No financial relationships or conflicts of interest

Case Diagnosis: 48 y/o female with past medical history of bipolar disorder and anxiety who presented with acute onset weakness and frequent falls.

Case Description: The patient presented for weakness starting in her lower extremities, leading to falls that began several days prior to presentation. She denied any history of diarrhea, recent illness or disease. Examination on admission revealed symmetric lower extremity weakness and loss of sensation and areflexia. Patient was presumed to have AIDP and completed a course of steroids and 5 days of IVIG with no noticeable improvement. Workup included testing for heavy metals, which returned positive for arsenic. The patient then underwent succimer chelation therapy for 14 days and was then admitted to an inpatient rehabilitation hospital. Electrodiagnostic studies obtained while in rehab showed symmetric, sensori-motor demyelinating polyneuropathy in the upper extremities and mixed demyelinating-axonal polyneuropathy in the lower extremities consistent with arsenic poisoning. Needle EMG showed widespread abnormal spontaneous muscular activity. The source of the toxicity remained unknown, as no household contacts were symptomatic and the patient had no known exposures to materials containing high levels of arsenic.

Setting: A Large Academic Medical CenterAssessment/

Results: During the patient’s rehabilitation stay, the patient experienced an improvement in her strength, but continued to have persistent paresthesias and decreased sensation in all her extremities.

Discussion: This case highlights a lesser known cause of symmetric polyneuropathy, as this case was initially thought to be AIDP. The inclusion of additional screening labs such as heavy metal levels was pivotal in coming to the proper diagnosis. The presence of Mee’s lines on the fingernails are an important clinical finding of heavy metal toxicity and can aid in diagnosis.

Conclusion: Arsenic poisoning presents with a similar clinical picture to AIDP and keeping heavy metal toxicity on the differential for symmetric sensorimotor neuropathy could prevent misdiagnosis and un-warranted therapies.

Level of Evidence: Level V

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PM&R Meeting Abstracts - https://pmrjabstracts.org/abstract/guillain-barre-as33-if-a-case-report/