Image IQ: Mitral valve prolapse with multiple petechiae

Image courtesy of VisualDx.

A 34-year-old woman with a history of mitral valve prolapse suddenly came down with a fever and chills soon after a dental cleaning. She appeared ill and her husband rushed her to the ED after they noticed that she had multiple petechiae on her fingers and hands. During her exam in the ED she mentioned that she was experiencing some vision loss and nausea.

What's your diagnosis?

A. Bacterial sepsis
B. Acute bacterial endocarditis
C. Systemic lupus erythematosus
D. Thrombotic thrombocytopenic purpura (TTP)

For guidance, refer to the differential builder on VisualDx.

See the next page for the answer.

ANSWER:  B) Acute bacterial endocarditis

Synopsis

Bacterial endocarditis is an infection of the endocardial surface of the heart. The most common structures of the heart affected are the heart valves. The term "acute" endocarditis is a clinical description of the rapidity of symptoms and is opposed to "subacute" endocarditis. Patients present acutely ill with fever and historically would die shortly after presentation. They may have signs of heart failure or present with embolic phenomena including stroke or Janeway lesions (painless erythematous macules that occur on the palms and soles). Certain causative organisms of endocarditis that typically present acutely and with a more fulminant course include Staphylococcus aureus and Streptococcus pyogenes. The viridans streptococci are classically associated with subacute progression of symptoms. However, it is known that certain organisms, including the enterococci, can present both acutely and subacutely. For this reason, clinicians now prefer to describe endocarditis by the etiologic agent responsible.

Patients at increased risk of this infection include intravenous drug users and patients with a predisposing heart condition including the presence of cardiac devices or prosthetic valves. Infection, including Candida infection, can occur after open heart surgery or valve replacement via catheter (TAVR).

Patients typically have fever. Cardiac murmur is usually present. On physical exam, there may be conjunctival hemorrhages, splinter hemorrhages, Janeway lesions, Osler nodes (tender, erythematous nodules that appear suddenly on the finger or toe pads), or Roth spots (pale lesions with surrounding hemorrhage seen in the fundi, with an ivory or white center surrounded by a red halo).

Imaging may reveal septic pulmonary infarcts, mycotic aneurysms, and stroke. Laboratory testing may reveal anemia, leukocytosis, elevated ESR, positive rheumatoid factor, hematuria, and red blood cell (RBC) casts in urine.

The diagnosis of endocarditis can be made by isolating the responsible organism in blood culture and by visualizing the valvular vegetation on echocardiography. Treatment is with prolonged antibiotics and sometimes with surgery to remove the source of infection.

For more information about this condition, incuding ICD 10 codes, visit VisualDx.

DISCLOSURE: This quiz was provided courtesy of VisualDx.