Kansas City, Mo.-based Truman Medical Centers is notifying 114,466 patients that their information may have been exposed.
In July, health system officials discovered that an employee's laptop had been stolen from his or her car. After an investigation, Truman Medical Centers learned that the laptop stored patient information.
Patient data that may have been exposed included names, dates of birth, medical record or patient account numbers, Social Security numbers, health insurance information, treatment information and clinical information.
There is no evidence that patient information has been viewed or misused, the health system said.
"We deeply regret any concern or inconvenience this incident may cause. We remain committed to protecting the confidentially and security of our patients' information. To help prevent something like this from happening in the future, we provided additional education to our employees about our policies against leaving laptops unattended. We are also making additional security enhancements, including installing controls on employee laptops," a statement releases from the health system said.