Mark Warner was a recurring character on House, M.D. during the first and second season. He is the husband of Princeton-Plainsboro's General Counsel Stacy Warner. He is recovering from acute intermittent porphyria which caused paralysis of the lower-half of his body. He works as a high school guidance counselor. He is portrayed by the actor Currie Graham.
Mark first appeared in the episode Honeymoon, when Stacy asked House to investigate his abdominal pain and mood swings. Despite his deep distrust of House both from a personal and professional standpoint, House managed to correctly diagnose his illness even though the test to confirm it was done without Mark's consent.
As Mark required a long period of convalescence to recover, Lisa Cuddy hired his wife to be the hospital's General Counsel. However, this severely strained the relationship as House made a point of both belittling Mark at every opportunity and putting the moves on Stacy at the same time. Eventually, Stacy became so close to House that Mark feared that he would lose her. However, eventually House himself stopped pursuing Stacy.
Mark's intense dislike of House is primarily due to the way House treated Stacy during their relationship.
Stacy Warner brought her husband's case to Dr. House. Mark was suffering from abominal pain, paranoia, and mood swings. Mark had been to several doctors, and none had found anything wrong with him. They put his symptoms down to stress from his work during the college application season. After Dr. House agreed to see Mark, Mark missed two appointments. Eventually, Stacy invited Mark to dinner without telling him that Dr. House would be there as well. After Mark realized he had been set up, he apologized to Dr. House and told him there was nothing wrong with him. However, Dr. House surreptitiously sedated Mark and had him transported to Princeton-Plainsboro Teaching Hospital in an ambulance he had arranged.
Dr. House brought the case to his team. They agreed that none of the tests showed anything that would cause abdominal pain or personality changes. Dr. Cameron wanted to know why Dr. House believed Stacy rather than Mark. Dr. House ordered them to re-do all the tests. If they were negative, he ordered an abdominal ultrasound. If it were negative, he ordered a CT Scan both with and without contrast.
All the tests were negative. Stacy wanted to keep testing, but Mark wanted to go home. Dr. House arranged for Dr. Ben Goldstein to do exploratory surgery. Dr. Cameron objected as there was no evidence Mark was ill and she thought it was premature. However, Dr. House insisted, saying that they had no other reasonable diagnosis.
Dr. Goldstein started the surgery. Dr. House asked Stacy if she had been cheating on Mark, and she realized that he asked to ensure that Mark was really paranoid and didn't just have a reason to be suspicious. She denied cheating on him. The surgery went well and Mark was taken to the recovery room. All Dr. Goldstein found was a distended bladder. At this point, Dr. Foreman agreed with Dr. Cameron that there was probably nothing wrong with Mark. However, Dr. House asked to see the video of the surgery.
After reviewing the video for several hours, Dr. House called back his team. He noticed tremors in the abdominal muscles that indicated abdominal epilepsy. This had been mistaken for normal peristalsis. They realized that Mark must have a neurological problem.
Dr. Foreman did an EEG and found abnormalities showing that Mark's axial nerves were dying. The most common causes were encephalitis and early onset Alzheimer's disease. Mark's parents had died in an automobile accident and there was no family history of dementia, so Dr. Cameron planned to test for tau proteins. Dr. House also ordered tests for encephalitis and an environmental scan for toxins.
Dr. Cameron told Stacy about the possibility of Alzheimer's, but she dismissed it as Mark had no signs of memory loss. The test was also negative. Dr. Chase and Dr. Foreman went to Mark and Stacy's house and found an abandoned mountain bike and a new yoga mat. They thought the change in exercise might indicate Mark had back pain. However, they also found a bottle of amphetamines at the back of a desk drawer.
Dr. Foreman brought the pills back to House and noted amphetamine abuse would explain the symptoms. However, Dr. House pointed out the prescribing physician had recently had his license taken away for writing improper prescriptions to teenagers, and that the date of birth of the patient showed he was 17. He figured that Mark had confiscated the pills from a student. He dismissed the switch to yoga as a sign of aging. As encephalitis had been ruled out, he thought Alzheimer's was still likely despite the negative test. He ordered a PET Scan.
Dr. Foreman explained to Mark that they were going to inject him with a marker and ask him questions so that the scanner could map out his brain function. His limbic system and frontal lobe checked out fine. However, Dr. House interrupted to ask Mark questions about his relationship with Stacy on the pretext that he wanted to check his long-term memory. However, Dr. Foreman completed the test, which showed no abnormalities.
Stacy confronted Dr. House about the personal questions, but he insisted they had a medical purpose. He also admitted that he didn't know what was wrong with Mark. He had ruled out Alzheimer's, encephalitis, an immune system problem and environmental causes. He was healthy, except that his brain was dying. The only thing they could do was wait for a new symptom to develop.
However, Mark soon complained of tingling in his toes, followed by numbness and lack of feeling. He asked that Stacy hold his hand, but Stacy was already holding it. Dr. House realized he was paralyzed.
The disease was mimicking a peripheral nerve disorder, but Mark had severe paresthesia and couldn't move his arms or legs. Dr. House thought it might be Guillain-Barre syndrome, but Dr. Foreman had already done an indirect Coombs test and there were no agglutinate or antibodies. When Dr. House wanted to start treatment for Guillain-Barre as he may not be producing antibodies, Dr. Foreman pointed out the only way he could have no antibodies for the test was if his immune system wasn't working. Dr. Cameron noted that if that were the case, if they didn't treat him, he couldn't fight it off himself. Dr. House noted treatment wasn't very dangerous - immunoglobulin and plasmapheresis. If he improved, that would confirm it.
They told Mark the paralysis might not be permanent, but all of a sudden Mark got paranoid and suffered an anxiety attack that was initially mistaken for anaphylactic shock. Dr. House ordered 2 mg of Ativan and Mark improved immediately.
Mark did not respond to the treatment. Dr. House broke the news to Stacy and started talking about how he was nice enough to take her to Paris, something he had revealed during the PET Scan. However, Stacy said they never went to Paris. Dr. House asked when Mark switched to yoga, and Stacy said it was about a month ago - the same time he started getting sick. Dr. House reviewed the PET Scan and found that when Mark said he went to Paris with Stacy he thought he was telling the truth - a delusion. Together with the other symptoms, this pointed to acute intermittent porphyria. Porphyria can't be tested for unless the individual's urine is tested while he is having an attack as it leaves no traces. Mark's switch to yoga could indicate that he was becoming sensitive to light and wanted to avoid mountain biking outside. House ordered hematin and glucose. However, Dr. Cameron pointed out the treatment was dangerous unless he did have porphyria.
Dr. House proposed a test. Porphyria only has a few triggers - barbiturates, alcohol and high levels of protein. He wanted to inject him with all of them at once and test his urine when he had an attack. However, he admitted that if Mark didn't have porphyria, they didn't know what effect the test would have on him. In addition, the attack itself could be fatal. Mark would not consent.
Stacy asked how much time he could have, but Dr. House said it was totally unpredictable - five minutes or six months, and any attack could be fatal. the only other test, HMB synthase mutation, would take four weeks. Stacy asked him to give Mark the cocktail, but Dr. House refused because it was Mark's call. However, Stacy pointed out that Dr. House usually pressures patients into agreeing, but he wasn't doing it, most likely because he wanted Mark to die.
Stacy went back to Mark to convince him to take the test. Suddenly, Dr. House showed up with the cocktail. Stacy supported Dr. House, but Mark objected. Dr. House tried to proceed, but Dr. Foreman stopped him, as did Dr. Cameron. Even Dr. Chase stepped in. Stacy begged him to proceed. Dr. House turned to go, but then surprised everyone and injected Mark. As he expected, Mark had an attack. Dr. Chase ordered 10 mg of Ativan because he thought it was a stroke. Dr. House looked at his vital signs which indicated otherwise. He ordered that a sample of urine be taken from the catheter bag, but it came out in the commotion. Instead, Dr. House took a large syringe and drew a urine sample straight from the bladder. He then ordered them to proceed with administering Atvian.
Dr. House tested the urine, which confirmed the porphyria when it turned purple after exposure to light. He ordered hematin and glucose. Mark improved rapidly, although he still had weakness and would require several months of physiotherapy.