A 25-year-old man presented to the office because he had been feeling tired and feverish for several weeks. He admitted to injecting heroin regularly in the last 2 months. On examination, he was febrile and had a heart murmur of which he was previously unaware. His fingernails showed splinter hemorrhages (Figure 52-1). His funduscopic examination revealed Roth spots (Figures 52-2 and 52-3). An echocardiogram demonstrated vegetation on the tricuspid valve. He was hospitalized and treated empirically for bacterial endocarditis. After his blood cultures returned Staphylococcus aureus, his regimen was adjusted based on sensitivities and continued for 6 weeks.
Splinter hemorrhages appearing as red linear streaks under the nail plate and within the nail bed. Although endocarditis can cause this, splinter hemorrhages are more commonly seen in psoriasis and trauma. (Reproduced with permission from Richard P. Usatine, MD.)
Roth spots that are retinal hemorrhages with white centers seen in bacterial endocarditis. These can also be seen in leukemia and diabetes. (Reproduced with permission from Paul D. Comeau.)
Close-up of a Roth spot, which is actually a cotton-wool spot surrounded by hemorrhage. The cotton wool comes from ischemic bursting of axons, and the hemorrhage comes from ischemic bursting of an arteriole. (Reproduced with permission from Paul D. Comeau.)
Bacterial endocarditis is a serious infection seen most commonly in patients with prosthetic valves; injection drug users; patients with HIV, especially those who use intravenous (IV) drugs; and patients who are immunosuppressed. Diagnosis is made using the Duke Criteria. Treatment is IV antibiotics or surgical valve replacement. Mortality, even with treatment, is 26% to 37%.
3 to 7.0 cases per 100,000 patient years.1
Historically more common in men; however, the incidence in women is increasing. Men 8.6 to 12.7 and women 1.4 to 6.7 cases per 100,000 person years, respectively1
Average age has increased from 46.5 years (1980–1984) to 70 years (2001–2006)1
Incidence in IV drug users is 3 per 1000 person years or 1% to 5% per year2
Incidence in HIV-positive IV drug users is 13.8 per 1000 person years2
Incidence of vegetations forming on intracardiac devices has increased from 13.8% (1998) to 18.9%3
Morbidity and mortality is increasing. It is ranked the 3rd or 4th most common cause of life-threatening infection.1
Seen in immunosuppressed patients with central venous catheters or hemodialysis patients.
Fifty percent healthcare-associated, 43% community-acquired, and 7.5% nosocomial4
Mortality ranges from 16% to 37%5
Patients with endocarditis who require surgery is increasing, now about 50%1