What Is Endocarditis? Bump on Man's Hand Reveals Rare Heart Infection

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In this photograph, surgeons (who are not involved in the case report described in this article) perform heart surgery in a French hospital. Thomas Samson/AFP/Getty Images

A strange bump on a 27-year-old man's hand turned out to indicate a serious health issue.

The bump (which can be viewed here) originally appeared as a small red patch of skin. However, over the course of two weeks it changed color to blue and began pulsating, according to a report of his case published Thursday in The New England Journal of Medicine. It eventually became so painful that he went to the emergency room.

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The man told medical staff that in addition to the odd lump, he'd recently lost 26 pounds and had been dealing with fevers, decreased appetite and night sweats for six weeks.

After a physical examination, his doctors revealed that the bump was an aneurysm, which appears when a blood vessel wall becomes weakened and starts to bulge. Although aneurysms are fairly common, in this patient's case, it helped reveal a more rare diagnosis: subacute bacterial endocarditis.

Endocarditis happens when bacteria or other germs enter the blood and infect the inner lining of the heart chambers and valves, according to the National Heart, Lung, and Blood Institute. Those with the infection usually have flu-like symptoms; however, it affects people very differently and can cause problems in areas other than the heart.

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Although the patient's doctors do not yet know how he contracted the infection, they believe it could be due to poor oral hygiene habits and a recent visit to the dentist for an unspecified procedure.

He underwent a heart procedure to replace his damaged aortic valve, which is located between the organ's left ventricle and aorta. In addition, he had surgery to repair the aneurysm on his hand. After two days of taking a six-week-long antibiotic, his fevers and night sweats went away.

While this case was unusual, it wasn't the first time something similar had occured. In 2001, a similar case report was published regarding a 26-year-old man who had an aneurysm on his hand, which turned out to be associated with endocarditis.