House even thinks Kaufman is "reasonably competent". He offers resources to help Kaufmann, but Kaufmann knows House's reputation and refuses to let him have any involvement with the patient, knowing House is capable of going behind his back if he disagrees with him.
However, Lisa Cuddy convinces House to keep working on the case. House has to waylay Martha M. Masters (and later set her up to commit an assault on a patient) in order to insure she won't interfere with the rest of his team. Behind Kaufman's back, they first give Arlene thiamine and then switch out her medication.
All of this merely confuses Kaufman, who with his department, has come up with reasonable diagnoses that House's team has reached already. House just disagrees with them. They finally decide they have to try to give Arlene amphotericin B behind Kaufman's back. However, before they can, Masters figures out what's going wrong and, despite House's threat to ruin her career, she rats them out to Kaufman.
Kaufman is furious at both Lisa Cuddy and House, and the incident convinces Arlene to try to leave the hospital. However, when she tries, House convinces Lisa to confront her mother. She does and Arlene agrees to stay. House finally diagnoses her with heavy metal poisoning and she recovers when they remove her faulty hip implant.