A patient of the practice that I work for no showed for a follow up visit to a work related injury. The employer came into the office to let know that he has also no showed at work and wasn't sure if he would be in for his appointment. A employee called the patient herself and when he could not be reached she proceeded to give the patients personal info to the employer. Is this a HIPAA violations?

Unless the employee gave prior written permission for the employer to have access to his medical information then it is a violation.

An employee of your practice supplied diagnostic and/or treatment info to the employer? Is this related to a workman's cop claim? In that case the employer might have been entitled to the information. But the employee should certainly have received permission from the office manager or equivalent before releasing any info.

Yes, without written authorization, it is a violation.

It depends on WHO in the employee's office she gave the info to. Because it is work-related, certain employees are allowed to have CERTAIN information about the case. Who has rights (HR director, etc.) should be clearly stated on any/all consent forms and outlined it company policy.