Differential Diagnosis
- Single most likely diagnosis
- Acute rheumatic fever: This diagnosis is the most likely due to the patient's recent history of sore throat, which could have been caused by a Group A beta-hemolytic streptococcal infection, a common precursor to acute rheumatic fever. The patient's symptoms of shortness of breath, fever, malaise, and the physical examination findings of jugular venous distension, bilateral ankle edema, and an S3 gallop are consistent with heart failure, which can be a complication of acute rheumatic fever. The erythematous, ring-shaped macules and patches over the trunk could be a manifestation of the rash associated with acute rheumatic fever.
- Other Likely diagnoses
- Viral myocarditis: This condition could explain the patient's symptoms of shortness of breath, fever, and malaise, as well as the physical examination findings of jugular venous distension, bilateral ankle edema, and an S3 gallop. The chest x-ray showing cardiac silhouette enlargement and prominent vascular markings in both lung fields also supports this diagnosis.
- Kawasaki disease: Although less likely given the patient's age and the absence of other classic symptoms such as conjunctivitis and cervical lymphadenopathy, Kawasaki disease could still be considered as it can cause cardiac complications and a rash.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Infection with Borrelia burgdorferi (Lyme disease): Although the patient's symptoms do not strongly suggest Lyme disease, it is essential to consider this diagnosis due to its potential to cause cardiac complications, including heart block and myocarditis.
- Systemic lupus erythematosus (SLE): SLE is a multisystem autoimmune disease that can cause cardiac, renal, and dermatological manifestations. While the patient's symptoms do not strongly suggest SLE, it is crucial to consider this diagnosis due to its potential severity and the need for prompt treatment.
- Rare diagnoses
- Other rare conditions that could potentially cause the patient's symptoms include autoimmune disorders such as juvenile idiopathic arthritis or other infectious diseases like endocarditis or pericarditis. However, these diagnoses are less likely given the patient's presentation and the absence of other supporting symptoms or laboratory findings.