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As she was about to leave the office of Marvin M. Lipman, Consumer Reports’ chief medical adviser, the retired social worker turned to him. “You didn’t say anything about my black-and-blues,” she said, pointing to several bluish-purple, quarter-size spots on her forearms. Lipman told her that they were the only signs of her advanced years. She smiled, rolled her eyes and left.

Bruises, the breakage of tiny blood vessels near the skin’s surface that result in a blackish-bluish-purplish discoloration, are a common complaint among patients in their 60s and beyond. Distinguishing between innocent bruising and bruising that’s due to serious, sometimes life-threatening diseases can be a challenge, even to an experienced practitioner.

Most bruises are harmless

Many studies have shown that easy bruising occurs in up to 55 percent of healthy people. This number increases with age, and easy bruising is responsible for — or part of — many office visits.

Many patients are annoyed by the appearance, which for some necessitates the wearing of long sleeves or makeup on the legs. But others are genuinely concerned that some serious problem is underlying those “black-and-blues” (“ecchymoses” in medicalese).

People of any age may simply be bruise-prone, always bumping into objects such as railings and open drawers. The resulting bruises are roughly equivalent to the severity of the blow and the size of the object, and both are usually easy to recall.

But the so-called senile purpura often seen in older adults — in skin thinned by long exposure to the sun and environment, and without the protective cushion of fat that disappears as the years go by — is almost always the result of a minor trauma that seemed like no big deal at the time. These ecchymoses usually number not more than two or three on an arm or leg and are not bigger than a quarter. As the blood is gradually reabsorbed, the pigments are broken down and fade to a greenish hue, then yellow, and then they’re gone.

Those benign ecchymoses usually appear on the arms and legs. When they occur on the face, neck, chest or abdomen, a cause other than the aging process has to be considered. In particular, bruises on sites other than the arms and legs — especially the face and neck — should prompt questions about abuse.

But some reveal problems

The ability of blood to clot properly usually prevents black-and-blues from enlarging. But certain medications or conditions that interfere with this can result in larger ecchymoses, including some on the torso. These include medications that thin the blood (aspirin; nonsteroidal anti-inflammatory drugs, such as ibuprofen and naproxen; warfarin; and newer oral anti-clotting agents) and dietary supplements such as fish oil, ginger, ginkgo biloba and ginseng.

The same can happen when the skin undergoes excessive thinning, as with the prolonged use of corticosteroids — by mouth, injection or inhalation — or when the body produces excessive amounts of cortisol. These rare conditions are Cushing’s disease and Cushing’s syndrome.

Almost any drug, including antibiotics, antidepressants and tranquilizers, can cause a decrease in blood platelets — cells necessary for clotting.

Platelet disorders can also cause ecchymoses, and more characteristically tiny red dots on the legs called petechiae. These look quite different from ecchymoses, which have a blotchy appearance.

Bone-marrow disease, such as leukemia (acute and chronic) and myelodysplastic syndromes, as well as liver and kidney disease, can all cause clotting problems and bleeding into the skin.

Time to call the doctor

Contact your doctor if:

•Ecchymoses or petechiae appear within a month of starting a new prescription or over-the-counter medication or supplement.

•Bruises are many, large or on parts of your body other than arms and legs.

•Bruises are accompanied by bleeding elsewhere (gums, stools, urine).

•In addition to bruises, you have a family history of a bleeding disorder.

•You are at all concerned about your bruising. Blood tests such as a normal complete blood count, prothrombin time (also referred to as INR) and activated partial thromboplastin time should provide reassurance by ruling out the majority of clotting disorders.

 Copyright 2017, Consumer Reports, Inc.

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