Culture-negative endocarditis is an infection and inflammation of the lining of one or more heart valves, but in which no endocarditis-causing germs can be found in a routine blood culture. This is because certain germs do not grow well in a laboratory setting, or some people have received antibiotics in the past that keep such germs from growing outside of the body.
Endocarditis is usually a result of a bloodstream infection. Bacteria can enter the bloodstream during certain medical procedures, including dental procedures or through intravenous injection using non-sterile needles. Then bacteria can travel to the heart, where they can settle on heart valves.
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Holland TL, Bayer AS, Fowler VG. Endocarditis and intravascular infection. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 80.
Review Date 12/4/2022
Updated by: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.