My fiancée had blood tests done at the VA Hospital in mid-may. On May 31st they told him he had a positive result for clamydia. But today on August 10th they told him he had a positive result for HSV 1 & 2. And they also said he had a reaction to the Hepatitus B serum. They showed on paper that those results were from the test he took in May. They never told her verbally or on any paperwork before today. What can we do about this?
What damages did he, or you, suffer from the delay in being informed? If none then there is not much of a case. If damages warrant speak to local malpractice counsel about initiating a claim under the Federal Tort Claims Act.
The quick answer to your headline question is, Yes, you can sue the VA for malpractice. There are some very annoying hoops and limits but it can be done.
The longer answer, taking into account the facts that you presented is, probably not to good effect. As the other attorneys indicated, you would have to show serious harm in order to recover anything at all. Also, you would have to show that it was actual malpractice by a professional. That means a failure to meet the minimum "standard of care." That is much different from, some clerk or orderly, or even CNA, didn't explain things clearly (or at all). That would not be a medical standard.
The good news is that you do have a course of action. Every VA facility has a Patient's Advocate that you can register a formal complaint with. They will likely try to talk you down, which is appropriate if that fixes the problem, but you can insist on a formal complaint. With the new administration such complaints and errors now go to the employee file and can be part of getting a bad employee fired. I recommend that you be clear on what harm actually happened (end result) and what changes you want to see to make it not happen again.