Factors Vary When Measuring Thyroid Levels; Of B-12 and Dementia
Dear Dr. Roach: I have taken Armour Thyroid for 57 years. My T4 and TFTI levels are normal, but my TSH level is low. Why is this? — M.P.
Answer: Armour Thyroid is a mixture of two hormones: T4 (thyroxine) and T3 (triiodothyronine). A low TSH means the body is sensing too high a level of T3 or T4 in the body. Since your T4 is normal, it is possible that your T3 is too high. A direct measurement of T3 would answer this question. If your T3 is high, your doctor will consider lowering your dose or changing you to T4 only.
Some doctors mix doses of T4 and T3, or use Armour, which contains both. Some endocrinologists recommend against using T3 at all, since the body converts the active T3 from T4 as it needs it, and giving T3 directly bypasses that safety mechanism. On the other hand, some people may not normally convert T4 to T3. The system is more complicated than it looks.
TSH also can vary a bit, so if you aren’t having symptoms of hyperthyroidism, it’s worth double-checking before making a decision to change your medications. A persistently low TSH puts you at higher risk for bone loss and atrial fibrillation.
Some physicians are against the use of Armour Thyroid since it is a natural product (desiccated thyroid gland) and that there may be batch-to-batch variability. However, I talked to the manufacturer, who informed me that T3 and T4 levels in each batch are standardized. Some patients feel passionately that Armour Thyroid treats symptoms better than synthetic levothyroxine. I don’t know of any study that has proven either marked variability in, or superiority in treating symptoms by, the Armour product. The choice is for the patient and physician.
Dear Dr. Roach: What is your opinion of monthly vitamin B-12 injections to deter dementia? Would taking an oral supplement be just as effective? — T.D.
Answer: Severe vitamin B-12 deficiency causes neurologic and psychiatric symptoms that can look like dementia. In those cases, B-12 works wonders. However, it’s important to note that B-12 is not effective in preventing Alzheimer’s disease.
Pernicious anemia is a condition where the body cannot absorb B-12 normally. Monthly injections often are used to treat this condition. However, daily oral B-12 supplements are just as effective for nearly everybody. Many of my own patients prefer to keep taking their injections, which surprises me.
Dear Dr. Roach: I am 87 years old. I have pus in my urine. The urologist has sent it out numerous times for examination, but results show no infection. What could be causing this? Is there any harm in this? — I.K.
Answer: White blood cells (pus) in the urine usually are there due to infection; however, repeated urine cultures showing no infection should make you think of other possibilities. White blood cells can come from the kidney itself. Some kidney diseases can cause white cells in the urine, but usually also demonstrate abnormal kidney function in blood tests. Chronic infection of the prostate can cause pus in the urine, but your urologist is the expert in diagnosing this. Some bacteria in the bladder or urethra, such as Ureaplasma, don’t easily show up in culture and need to be specifically looked for
A rare cause, but one in all the textbooks and which I dutifully learned, is tuberculosis of the kidney. I have looked but have never seen a case. A kidney doctor may be the next place to go.
Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or write to P.O. Box 536475, Orlando, FL 32853-6475.