Enteroviruses — clinical association: Coxsackievirus B3 most commonly presents with which of the following conditions?

Introduction / Context:
Enteroviruses include polioviruses, Coxsackieviruses (A and B), echoviruses, and others. Each group shows characteristic clinical associations. Coxsackievirus B serotypes are notorious for cardiac involvement, especially myocarditis, which ranges from mild chest discomfort to fulminant heart failure.

Given Data / Assumptions:

• Coxsackievirus B3 is a non-enveloped, positive-sense RNA enterovirus.
• We seek the clinical syndrome most classically linked to Coxsackie B3.
• Differentials include mucocutaneous and ocular conditions attributed to other agents.

Concept / Approach:
Coxsackie B viruses (including B3) are strongly associated with myocarditis and pericarditis, as well as pleurodynia (Bornholm disease). While enteroviruses can occasionally cause diarrheal illness, Coxsackie B3’s high-yield association in exams is myocarditis.

Step-by-Step Solution:
Match “Coxsackie B3” with cardiac tropism: myocarditis/pericarditis. Exclude options classically caused by other pathogens or groups. Select the single best association: myocarditis.

Verification / Alternative check:
Case clusters link Coxsackie B infections to sudden cardiac dysfunction in young adults; pathology shows lymphocytic infiltration of myocardium following viral replication.

Why Other Options Are Wrong:

• Acute hemorrhagic conjunctivitis: Commonly due to Enterovirus 70 or Coxsackie A24 variant, not Coxsackie B3.
• Muscular dystrophy: Genetic disorders, not viral infections.
• Gastroenteritis: Enteroviruses can affect the gut, but B3’s hallmark association is myocarditis.
• Herpes labialis: Caused by herpes simplex virus, not an enterovirus.

Common Pitfalls:
Equating all enteroviruses with generic “GI disease”; specific serotypes have distinct tropisms.

Final Answer:
Myocarditis is the condition most commonly associated with Coxsackievirus B3.