Employees who store medical records on laptops must use systems that run either on Microsoft's Windows operating system or Linux.
Article is here:

http://www.freerepublic.com/focus/f-chat/1997457/posts

In the wake of a widely publicized security breach that left thousands of patient records exposed, the federal government's National Institutes of Health is forbidding all employees who use Apple's MacBook laptops from handling sensitive data as of Friday, InformationWeek has learned. Employees at the health agency who store medical records and other personal information on laptops must use systems that run either on Microsoft (NSDQ: MSFT)'s Windows operating system or Linux, according to an agency memo.
Apparently the underlying issue is that the PointSec security software won't run on them, and that happens to be the NIH "standard".