San Antonio Express-News (Sunday)
Meds necessary after kidney transplant
Q: I had a kidney transplant nine years ago. Other than a bout with COVID that landed me in the hospital a couple of months ago, I have been rather healthy and lead a normal life. I take a handful of pills each day that are mainly aimed at suppressing my immune system so I do not reject my new kidney.
My question is, after nine years, wouldn’t my body have accepted this new organ as its own and the immunosuppressant drugs would no longer be necessary?
A: I am glad to hear you are doing so well. A kidney transplant leads to a longer and better quality of life than dialysis does for most recipients.
Besides being a precious gift, a kidney has an enormous source of foreign proteins that your body desperately wants to get rid of. The system is complex, but your body doesn’t recognize your transplanted kidney as a part of you due to the presence of specific and major histocompatibility antigens that aren’t yours.
Your immune system sees this kidney like an invader — such as an infection or a cancer — that it needs to get rid of. The handful of pills you take is precisely dosed to keep your immune system from destroying your transplanted kidney but not so suppressed that it can’t respond to real infections and cancers.
Over time, you may need slightly less immunosuppressive medication, but your body will never stop seeing the transplanted organ as anything other than foreign. There may be an exception in infants whose immune systems aren’t fully developed and won’t recognize the organ as an invader. This has been reported with heart transplantation in infants but not in adults with fully formed immune and inflammatory systems.
So, don’t stop your medication. Your body will quickly reject the organ, and you will require powerful medication to try to stop the rejection. This then makes you susceptible enough to bacterial and viral infections that will mandate antibiotics and antivirals, in addition to the medications to stop your body from rejecting the kidney.
Q: I read that nicotine is antiparasitic. I suspect that a nicotine patch may keep bird mites from biting patients. Do you have any information on this? We currently have an invasion in a patient.
A: Nicotine is known to have antiparasitic properties, but I couldn’t find any data to support the use of a nicotine patch to prevent bird mites from biting a human.
Bird mites, which are tiny and associated with many bird species (especially pigeons), can bite humans but cannot complete their life cycle on humans. So, getting rid of the birds and their nests is usually adequate enough to stop the problem. A pest-control professional should be able to treat the home.
Bird mite bites look very much like bedbug bites. In the short-term, DEET is effective
to ward off mites and keep them from biting people. I did read a case report of gerbils being an unexpected host of bird mites, so you might want to ask about that.
Q: I had a knee replacement about six years ago. At the time, I was in considerable pain, and it dissipated slowly after the operation. After about six months, I still had some pain, but the surgical doctor I used had retired. So, he just gave me my medical history and closed his office. He was a one-man operation.
I still had pain, but it was tolerable. However, had I known I would be left with more pain than I had before my operation, I wouldn’t have proceeded with the operation. Recently, I saw another orthopedic doctor who took X-rays and said that everything was excellent and looked good, but I still have pain and stiffness in my knee.
I now need a hip replacement on the same side. Is there anything I should be asking, or can some sort of MRI or other scan reveal an abnormality with my knee? I’m really afraid of being left with more pain than I have now.
A: Being left in more pain than when you started is an unfortunate outcome with a joint replacement. Usually, there is a reason for the pain (such as an infection) that can be found and sometimes corrected. But it sounds like you have been one of the unfortunate ones in whom the operation really was a failure — at least in terms of pain, which is a very important outcome.
The ability to do more activities is another major benefit that is hoped for and expected with a joint-replacement surgery.
Approximately 20% of people have persistent pain after a knee replacement. I am by no means an expert, but patients with persistent pain often do get an MRI to look for surgical complications, including loosening and instability.
One other condition that I saw in one of my own patients was metal hypersensitivity; my patient was known to be quite allergic to nickel, and the surgeon put in a nickelcontaining prosthesis. She continued to have pain until it was removed and a new prosthesis was placed.
Q: I am 56 and have been experiencing frequent urination lately. I have to urinate almost every hour, and I also become thirsty very often. The more I drink water, the more often I urinate. What could be the possible health challenge?
A: Frequently urinating small amounts of fluid generally means a urine infection, an overactive bladder, or prostate problems in men, but I think you are specifically talking about large amounts of urine output.
The classic combination of excess thirst (“polydipsia”) and excess urination (“polyuria”) is a sign of diabetes mellitus. With diabetes mellitus, high sugar in the blood cannot be adequately removed by the kidney and is excreted through the urine, bringing water along with it. This forces the person to drink more, which leads to salt and water imbalances. (Diabetes insipidus can also cause similar symptoms but is much less common.) These conditions can be easily tested for with the most basic metabolic tests.
However, I have also seen people, both interns and patients, who “chase their tail.” What goes in must come out, so the more you drink, the greater the need to urinate. Many people believe that the more water you drink, the healthier you are, and that’s just not true.
I very frequently see patients in trouble from excess water drinking. (This is much more likely in older people, those with kidney disease or those taking medications that affect the ability of the kidney.)