MRI of the head, toxicology screening, and neurologic consultation should be considered in all adults aged ≥18 years with sudden-onset amnesia, particularly in patients with altered consciousness. Advanced laboratory testing, including testing for synthetic opioids (eg, fentanyl) and their analogues, as well as extraneous substances not assessed in these reported cases, might further clarify an association with substance use.

Acknowledgments

Juan Small, Monroe Butler, Yuval Zabar, Lahey Hospital and Medical Center; Michael Lev, Massachusetts General Hospital; Joshua Klein, Brigham and Women’s Hospital; Mara Kunst, L&M Radiology; Chun Lim, Beth Israel Deaconess Medical Center; Benjamin Kerman, Brigham and Women’s Faulkner Hospital.

Reprinted from: Barash JA, Somerville N, DeMaria A Jr.. Cluster of an unusual amnestic syndrome—Massachusetts, 2012–2016. MMWR Morb Mortal Wkly Rep.2017;66:76-79.

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Dr. Barash is with Lahey Hospital and Medical Center in Burlington, Massachusetts, and Soldiers’ Home in Chelsea, Massachusetts. Dr. Somerville is with Epidemic Intelligence Service, Centers for Disease Control and Prevention. Dr. DeMaria is with the Massachusetts Department of Public Health in Jamaica Plain.