Quest Diagnostics takes lab portal offline after unauthorized access
Quest Diagnostics reported that an intruder accessed its Quanum LSM lab-services portal on October 21, 2026, and some patient records may have been exposed. The company said it contained the activity, is working with outside investigators and law enforcement, and has not determined which data types were affected. Quanum LSM remains offline, and customers are being told to use paper requisitions or Quanum eLabs while other systems are temporarily restricted.
Quest Diagnostics is a large U.S. clinical laboratory, with 7,700 locations across North America, about 65,000 employees, and more than $11 billion in yearly revenue. Its Quanum LSM portal lets physicians and medical-office staff order tests, view results, check status, and request supplies.
After learning of the October 21, 2026 access, Quest filed an SEC notice and posted a website alert. It said some patient records may have been exposed, though affected data types remain unclear. The company paused other systems, including Essential Insights and LabHQ, while direct-customer LIS and EMR interfaces were unaffected.
The incident could affect patients whose records were handled through Quanum LSM, as well as clinics and hospital staff who rely on the portal for orders and results. If exposed data includes sensitive health details, patients may face privacy risks and possible fraud concerns, though the company has not confirmed what data was involved. Temporary workarounds such as paper requisitions could slow some workflows, while the prior breach litigation may heighten scrutiny of how Quest protects patient information.