Question: A friend of ours had a bad leg clot (DVT). What surprised me is he has cirrhosis of the liver. I thought people with cirrhosis have bleeding problems. Can you tell me how he could get a clot?
Answer: You're correct folks who have severe cirrhotic liver damage have clotting problems due to an inability of a damaged liver to make adequate proteins necessary for proper clotting to occur, a decreased number of platelets (clot cells) and an impairment in the function of existing platelets. But we also occasionally see DVT leg clots and pulmonary embolisms (lung clots) due to a cirrhotic liver's decreased production of anti-clotting proteins. Here's why: the healthy liver makes some proteins that assist with clotting as well as regulatory proteins that squelch clotting pathways to keep the clotting process balanced. A cirrhotic, scarred liver lacks a normal clotting balance.
It's difficult for doctors to predict who is at risk for a serious clot. Simply looking at blood clotting tests like an increased prothrombin time (PT), an increased INR level or a low platelet count cannot assure us of a low risk of serious clots. We once thought folks with cirrhosis/end-stage liver disease were "auto-coagulated" (i.e. - protected against clots as though they were on a blood thinner like Coumadin), but as you've seen in your friend's situation, that's not the case. One last thing to be aware of: an undetected cancer somewhere in the body can trigger pro-clotting proteins that cause abnormal clots. Always consider that in the setting of an unexplained blood clot.
Question: I've been hearing a lot about the U.S. Preventive Services Task Force making recommendations about the need for things such as PSA blood tests and mammograms under a certain age. Who are they and what is their agenda?
Answer: The USPSTF is a quasi-governmental group of 16 experts in preventive and evidence-based medicine that operates under the auspices of the Agency for Healthcare Research and Quality. Their "good versus harmful," cost-conscious agenda is to make evidence-based recommendations on whether or not there's a need or benefit to many of the common clinical preventive services performed by doctors in the United States.
A number of their recommendations have been controversial, and the USPSTF has been criticized for reaching conclusions without proper input from specialty societies (e.g. - American College of Radiology or the American Urological Association) or established experts in each field.
While they have made a number of good recommendations, some of their controversial recommendations include:
1. No routine screening for colorectal cancer for folks older than the age of 75
2. No screening for testicular cancer in adolescents and adult males
3. No PSA screening for prostate cancer
4. No mammograms until age 50
5. No routine use of aspirin to prevent colorectal cancer
6. No routine EKGs in asymptomatic folks, and insufficient evidence to recommend for or against routine EKGs in folks at high cardiovascular risk
7. Insufficient evidence to recommend for or against routine screening for glaucoma
8. Insufficient evidence to recommend for or against routine screening for thyroid disease in adults
9. No routine screening for peripheral arterial disease
10. No value to teaching patients how to do a self-breast examination
Dr. Mitchell Hecht is a physician specializing in internal medicine. Send questions to him at: "Ask Dr. H," P.O. Box 767787, Atlanta, Ga. 30076.