Common Bacterial or Fungal Infections Can Put Your Heart at Risk


It’s a rare occurrence, but common bacteria or fungi found in your mouth, skin and elsewhere in your body can sometimes put your heart at risk.

The resulting illness, infective endocarditis, is very serious if not treated quickly. Early detection is critical, so it’s a good idea to know what to look for — especially if you have a weak heart.

In this Q and A, infectious disease specialist Nabin Shrestha, MD, discusses what you should know about endocarditis and how doctors treat this condition.

Q: How do you get endocarditis?

A: Common bacteria or fungi can get into your bloodstream — during a dental visit, when you brush your teeth,or when you pass stool, for example.  A healthy heart usually can resist infection, but sometimes infection takes hold and attacks heart valves.

Bacterial infections are more common. There are four groups that can cause endocarditis:

Fungal infections account for about 3 percent to 4 percent of all cases. They typically are caused by different species of Candida.

Q: Are some people more likely to get endocarditis?

A: There is a risk any time bacteria gets into the bloodstream. But you’re at higher risk if you:

Q: What symptoms should you watch for?

A: Fever and fatigue are the most common symptoms. If you were previously healthy, you likely will notice a significant change in your overall sense of well-being.

However, if you have valve disease and already are tired and weak, your underlying condition may mask the fatigue from endocarditis. Watch for a clear worsening of your condition.

Q: How will your doctor diagnose endocarditis?

A: If your doctor suspects endocarditis, he or she will take two or more blood cultures to look for bacteria or fungi in the blood. The blood cultures usually are taken from two sites to make sure that bacteria isolated are real, and not contaminants from the skin.

Your doctor then will likely request an echocardiogram, an ultrasound of the heart, to look for heart valve abnormalities.

Q: Are there times when diagnosis is more difficult?

A: One of the biggest challenges we face is when endocarditis is not recognized and treatments have been given for a mistaken diagnosis of pneumonia or other presumed infection. Antibiotics can mask the identification of bacteria in blood cultures and make it hard to make a definitive diagnosis.

Q: How do you treat endocarditis?

A: Treatment includes antibiotic therapy, which kills the bacteria. However, many patients also need surgery to either repair or replace the damaged heart valve. Sometimes it is not possible to control the infection with antibiotics alone, and surgery may become necessary.

For those with artificial heart valves, antibiotics typically can’t cure the infection and a surgeon will have to replace the infected valves.

Fungal infections are more severe and more frequently require surgery.

Q: How effective is surgery?

A: It is usually a complicated procedure and, for most people, the first 30 days after surgery often are rocky. If they get through that, it is quite successful.

People who inject drugs often have a relapse within about six months if they continue to use drugs. This is because they are more susceptible to a second infection after having a first one, particularly if their freshly replaced valves are exposed to bacteria that might be introduced while injecting drugs.