The personal information of some Northwestern Memorial HealthCare patients, including some Social Security numbers, might have been on an employee’s laptop that was stolen in October, the hospital group announced this week.

Hospital officials determined the laptop, which was inside an employee’s vehicle stolen Oct. 21, may also have contained names, addresses, diagnoses, dates of birth, health insurance information, billing codes, dates of services, physicians’ names, medical record numbers and treatment information about some patients of Northwestern Memorial Hospital, Northwestern Lake Forest Hospital and Northwestern Medical Group, the hospital group said.

Northwestern Memorial HealthCare said it began mailing letters to affected patients Friday.

“At this time, we have no knowledge that this information has been used in any way,” the group wrote in a news release.

The stolen laptop was password protected, but patients’ information was not encrypted. Although Northwestern Memorial HealthCare has a policy of encrypting laptop computers, the group said it is taking steps in response to the incident to ensure staff laptops are encrypted.

The corporation advises patients who do not receive a letter by Jan. 9 and who believe their information may have been stolen to call the Northwestern Memorial HealthCare response line at 888-266-9276.

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