Differential Diagnosis for New Murmur in Patient with Dental Infection

• Single Most Likely Diagnosis
  • Infective Endocarditis: This is the most likely diagnosis because dental infections can lead to bacteremia, which can then infect the heart valves, resulting in a new murmur. The proximity of the dental infection to the bloodstream increases the risk of bacterial seeding on the heart valves.
• Other Likely Diagnoses
  • Non-bacterial Thrombotic Endocarditis (NBTE): Although less common than infective endocarditis in the context of dental infections, NBTE can occur, especially if there's an underlying condition like malignancy or sepsis not directly related to the dental infection.
  • Rheumatic Heart Disease: If the patient has a history of untreated streptococcal infections (which could be related to the dental infection), this could potentially lead to rheumatic fever and subsequently rheumatic heart disease, manifesting with new murmurs.
• Do Not Miss Diagnoses
  • Prosthetic Valve Infection: If the patient has a prosthetic heart valve, any infection, including dental infections, poses a significant risk of prosthetic valve endocarditis, which is life-threatening and requires immediate attention.
  • Marantic Endocarditis: In patients with significant underlying diseases (e.g., cancer), marantic endocarditis (non-bacterial thrombotic endocarditis) can occur, and while less directly related to dental infections, it's crucial not to miss due to its implications on patient management.
• Rare Diagnoses
  • Libman-Sacks Endocarditis: Associated with systemic lupus erythematosus (SLE), this form of non-bacterial endocarditis is rare but could be considered in patients with a history of SLE and a new murmur, even if they have a dental infection.
  • Cardiac Tumors: Although extremely rare, cardiac tumors could potentially cause new murmurs. The presence of a dental infection might coincidentally precede the discovery of such a tumor.